create a hypothesis of how life will be in 2100

How many humans tomorrow? The United Nations revises its projections

Anthropologue et démographe, professeur au Muséum national d'histoire naturelle et chercheur associé à l'INED, Muséum national d’histoire naturelle (MNHN)

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In 2019 the planet has 7.7 billion inhabitants, which is likely to rise to 8.5 billion in 2030 and nearly 10 billion in 2050. These figures are taken from the world population projections just released by the United Nations .

They correspond to the medium scenario in which fertility, which is 2.5 children per woman today worldwide and decreases year by year, continues to decline to 2.2 children in 2050 and 1.9 in 2100. Under the high scenario, fertility declines less rapidly, with a level of 0.5 children above the medium scenario, and the world population would reach 10.6 billion by 2050. In the low scenario, it decreases faster and is 0.5 children below the medium scenario, with the population reaching only 8.9 billion by 2050. Extending the projections leads to 10.9 billion inhabitants in 2100 in the medium scenario and, respectively, 16 and 7 billion in the high and low scenarios (Figure 1).

3% fewer people in 2100 than projected two years ago

These new projections replace those that the United Nations published in 2017. The calculations have been revised upwards or downwards according to the countries or regions. For example, in the medium scenario, the figure for China in 2100 is 44 million higher than that in the 2017 projections (4% more). In contrast, for India, it is down 66 million (4% less). The same goes for Africa as a whole, whose projected population in 2100 is reduced by 187 million (-4%). For the planet as a whole, the upward and downward revisions offset each other, but only partly. According to the medium scenario, the global total for 2050 is projected to be 37 million fewer people than in the previous projections (-0.4%) and 309 million fewer in 2100 (-3%).

The UN revises its population projections every two years. Like those just released, the changes from the projections released two years earlier look small. But when accumulated over several decades, they become significant.

Projections have changed a lot in 40 years

The first time the United Nations published population projections up to 2100 was in 1981, and their medium scenario predicted then that the world population would reach 10.5 billion that year. The June 2019 projections suggest a figure of 10.9 billion – 0.4 billion higher. While the world total is slightly higher, it conceals a radical change in population distribution across the different continents. In 1981, the population of Asia was projected to reach 5.9 billion by 2100, but in 2019 the figure was revised downward to 4.7 billion (20% less). Likewise, for Latin America, the figure of 1,187 million in 2100 was lowered to 680 million (a decrease of about 43%). For Africa, on the other hand, the 1981 projections were 2.2 billion for 2100, while the 2019 projections have nearly doubled this figure to 4.3 billion (see Figure 2 below).

Mortality has declined more than expected

Where do these changes come from? The population of a country or continent changes because of fertility and mortality. Migration is also a factor, but to a lesser extent for many countries and with zero effect worldwide. It is therefore the assumptions on mortality and fertility that affect projections. For mortality, it declined faster than imagined 40 years ago, especially for children, which led to more rapid growth. The AIDS epidemic was certainly not anticipated at the time, and Africa has paid the heaviest cost. But the excess mortality it has caused will have lasted only one-time, and life expectancy has begun to increase again in recent years and relatively quickly. AIDS has had little effect on the demographic vitality of Africa.

The changes in assumptions that ultimately had the larger effect on the projections are those concerning fertility, the evolution of which was revised following various surprises.

Replacement of generations?

Nearly 40 years ago, the UN’s medium scenario population projections were based on future fertility of close to 2.1 children per woman everywhere in the world. In countries already below this – like most industrialized countries – it was forecast to rise incrementally to 2.1, then flatten out. In higher fertility countries, it was projected to fall to 2.1 and then level off.

This threshold corresponds to the replacement of generations – each couple is replaced on average by two children becoming adults themselves – and choosing it as the level of convergence assumes a long-term stabilization of the world’s population as well as that of each region composing it. Hence, in the 1981 projections, each region’s or country’s population curve plateaus once the growth phase has ended (Figure 2 above).

The evolution of fertility

However, the observed fertility trends were different and the scenarios had to be revised to take into account several surprises.

First surprise: fertility has remained well below 2.1 children in many industrialized countries. And many Southern countries have joined the countries of the North in low fertility. Consequently, the United Nations has abandoned its hypothesis of convergence to 2.1 children to adopt a convergence level well below: 1.85 children (Figure 3 below). The population curves then has a bell-like shape almost everywhere: after reaching a maximum, the population decreases (Figure 2 above).

The second surprise came 30 years ago, when surveys revealed the unexpectedly rapid pace of fertility decline in many countries of Asia and Latin America. In response to this new trend, the United Nations made substantial downward revisions to their demographic projections for these continents.

A third, more recent surprise concerns intertropical Africa . Fertility decline in this region was expected to begin later than in Asia and Latin America due to slower social and economic development, but it was assumed that the rate of decrease would be similar to that assumed for other regions of the Global South.

This is indeed the case in North and Southern Africa but not in intertropical Africa, where the fertility decline is occurring more slowly . This explains the upward revision of projections for Africa, which could be home to more than a third of the world’s population by 2100 .

These figures are projections, and the future is not written. However, demographic projections are quite reliable for predicting population size in the short-term future, i.e., over periods of 10, 20 or 30 years. As for more distant projections, they will undoubtedly be revised following the surprises that the future holds for us.

This article was originally published in French

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What will it be like to live in a megacity in 2100?

Image: A woman walks at the Bund in front of the financial district of Pudong in Shanghai. REUTERS/Aly Song

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Stay up to date:, youth perspectives.

“The street finds its own use for things”, William Gibson, famed science fiction author, once wrote. Whatever a technology is designed for, the people who use it, and the environment it’s used in, will adapt it to suit other needs.

How might his insight come to life in the year 2100? The advent of advanced machine intelligence , automation technologies, urbanisation and the increasing connectivity between human and machine offer interesting prospects.

By 2100, as much as 84% of the Earth’s 10.8bn people will live in cities, according to the UN. Potentially dozens more megacities—cities with populations of 10m or more, 28 of which exist today, will pepper the planet—with developing countries accounting for almost 89% of the growth.

Source: Cisco

Coupled with a world rocked by climate change, however, these megacities may not be the shimmering and delightful Emerald City traditionally envisioned by futurists and science fiction. Some, notably coastal ones like New York or Shanghai, will have to adapt their structure to account for and protect themselves from rising sea levels as well as extreme weather events—be they hurricanes like Sandy or heat waves like those recently blanketing parts of India.

Humans won’t be the only inhabitants of these megacities of the 2100, however. Machines—and robots—will be integral to their ecosystems. According to Cisco, some 50bn machines are already projected to be connected to the Internet by 2020 alone, dwarfing the number of connected humans almost 10:1. While estimates for the year 2100 do not yet exist, the trend is likely to continue.

Combined with the continued rise of machine intelligence, this network of—perhaps trillions?—of connected machines will help cities make sense of any activity within their boundaries. “These machines won’t just be external objects in the world, but will be embedded in both us and our environment, seamlessly connecting us and immersing us in the cities we live in,” says Alessandro Voto, a researcher at the Institute for the Future, a think tank based in Silicon Valley.

An obvious application, currently in development, will be coordination of transportation and logistics though drone networks or driverless vehicles, both of which—thanks to AI—would require limited human intervention by 2100.

Health sensors, similar to Proteus Digital Health’s patch although probably implanted into the body by then, will connect with physical environments and healthcare systems, notifying users of changes in vital signs or potential danger, such as a heart attack or hypoglycemia.

With advances in bionics and human augmentation technologies like neural prosthetics, humanity’s connection with machines will likely feel as natural as we now feel with one another. Already today, bionic limbs allow for amputees and paraplegics to control physical systems telepathically. Tomorrow, we may find ourselves controlling the life unfolding in cities with our minds and vice versa. “This deeply complex web of intention and influence will adapt the world to the needs of its diverse participants, reprogramming the material, machine and biological systems that make up daily life,” Mr Voto continues.

Despite its advantages, not everyone is likely to go for this fully integrated life, however, and many will remain “unplugged”—by choice or for economic reasons.

Still, invoking William Gibson, we’ll always find our own uses for things. And as we grow increasingly synchronous with our technologies, the streets of tomorrow may equally find their own use for us, too.

Author: Andrew Trabulsi is a consultant, author, and entrepreneur with a background in technology forecasting, geopolitics, and economic development policy.

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Author Interviews

'physics of the future': how we'll live in 2100.

Imagine being able to access the Internet through the contact lenses on your eyeballs. Blink, and you'd be online. Meet someone, and you'd have the ability to immediately search their identity. And if your friend happens to be speaking a different language, an instantaneous translation could appear directly in front of you.

That might sound farfetched, but it's something that might very well exist in 30 years or less, says theoretical physicist Michio Kaku.

"The first people to buy these contact lenses will be college students studying for final exams," he tells Fresh Air 's Terry Gross. "They'll see the exam answers right in their contact lenses. ... In a cocktail party, you will know exactly who to suck up to, because you'll have a complete read out of who they are. President Barack Obama will buy these contact lenses, so he'll never need a teleprompter again. ... These already exist in some form [in the military]. You place [a lens] on your helmet, you flip it down, and immediately you see the Internet of the battlefield ... all of it, right on your eyeball."

But Internet-ready contact lenses aren't the only futuristic item we're likely to see. Kaku describes some of the inventions that may appear throughout the coming century — based on developments currently taking place in nanotechnology, astronautics, medicine and material science — in his book Physics of the Future . Kaku details some of these inventions, including disposable computers, space elevators and driverless cars — which will likely be ready in the next decade and will completely eliminate the need for high school driver's ed classes.

"In the future, you'll simply jump into your car, turn on the Internet, turn on a movie and sit back and relax and turn on the automatic pilot, and the car will drive itself," he says. "Unlike a human driver, it doesn't get drunk, it doesn't get distracted and certainly does not have road rage."

The cars will be equipped with radar in the fenders that will communicate with road signs and sensors along highways.

"When the car comes to an intersection, the GPS system will alert the computer [inside the car] that there is an intersection coming up," he says. "[The GPS system] will look onto the [roadside] sensor and then slow down."

Kaku also explains how, in the future, our brains might be able to interface with artificial intelligence. He describes one study in which computer chips were placed into the brains of paralyzed stroke patients at Brown University. The patients learned that by thinking certain thoughts, they could manipulate a cursor on a computer screen.

Michio Kaku is an author and the Henry Semat Professor of Theoretical Physics at the City University of New York. His books include Hyperspace , Visions and Beyond Einstein . Andrea Brizzi/Doubleday hide caption

Michio Kaku is an author and the Henry Semat Professor of Theoretical Physics at the City University of New York. His books include Hyperspace , Visions and Beyond Einstein .

"It takes awhile — it takes a few hours — but after a while, you realize that certain thoughts will move the cursor in certain directions," he says. "After a while ... [the patients] were able to read email, write email, surf the Internet, play video games, guide wheelchairs — anything you can do on a computer, they can do as well, except they're trapped inside a paralyzed body."

Similar technology could be used in the future to control robots that can go places where humans can't, says Kaku.

"It's very dangerous to put astronauts on a moon base where there's radiation, solar flares and micro meteorites," he says. "It'd be much better to put robots on the moon and have them mentally connected to astronauts on the Earth. So you'd go inside a pod, you mentally make certain thoughts, which then [could] control the robots on the moon."

Kaku, a professor of theoretical physics with the City College of New York, also talks about his childhood, his work with Edward Teller, a member of the Manhattan Project, and his work on the development of string field theory. He is the author of several books, including Physics of the Impossible , Parallel Worlds and Beyond Einstein . He has also hosted scientific documentaries for the Discovery Channel, the BBC and the Science Channel.

Will the Earth be habitable in 2100?

Flaming earth graphic from Al Gore film "An Inconvenient Truth"

The blame game

A couple of years ago, I accepted an interview request from a conservative radio host. It was about the time that Drew Gronewold and I were talking about high water levels on the Great Lakes. We maintained a warming climate could produce both record-high and record-low lake levels . Critics latched onto this statement as proof that climate scientists attribute anything we want to global warming. I understood that criticism, and I wrote a little piece called “ Actually, climate scientists don’t blame anything they want on climate change .”

I researched the radio host and was prepared to meet for a productive conversation. I focused on a couple of key concepts, and as we closed, he asked how I felt about dire predictions made by the Intergovernmental Panel on Climate Change (IPCC). Did I believe the world was going to end in 10 years, he asked, “as the IPCC said?”

“Of course not,” I replied, and we spoke for another 30 minutes.

That interview never aired. Why? It did not play into the polarized narrative of the talk show’s business model.

The question of habitability

The amazing underground tunnels that bring water to form the Turpan Oasis in Northwest China provide historical testimony to humans’ abilities to adapt. (Colegota, CC BY-SA 2.5 ES)

More recently, a Michigan alumnus asked me a similar question. “If we do not meet the goals of the Paris Agreement, do you think the Earth will be uninhabitable in 2100?”

Again, the short answer is, “Of course not.”

If Earth is uninhabitable in 2100, it will not be because our climate cannot support human life.

As always, my longer answer requires context.

The two different questions arise from the same place. In 2018, the IPCC released Global Warming of 1.5 ° C: An IPCC Special Report . The media covered it widely, often using such extreme headlines as “ The world has just over a decade to get climate change under control, U.N. scientists say .”

But as we consider the question of habitability, we should recognize that immense ranges of temperature and precipitation already characterize the Earth’s climate. People have adapted to extreme cold in Siberia. Others are thriving in the hot, arid Middle East. The amazing underground tunnels that bring water to form the Turpan Oasis in Northwest China provide historical testimony to humans’ abilities to adapt.

In the climate of 2100, there will be plenty of environments between these current extremes. Hence, it is safe to conclude that Earth will be habitable.

Sustaining life

In the 1965 film Dr. Zhivago, starring Omar Sharif, the endless Russian winter became a character in its own right A set in Spain doubled for the oppressive, soul-crushing Siberia. (MGM, 1965.)

Though humans have adapted to these extremes, they do not support large populations. More targeted questions for 2100 may be: How many people can the planet support? How many will have access to technological adaptation strategies, such as floating cities? Does the human species have the ability to maintain planet-supporting infrastructure?

Humans have, always, experienced changing climates and harsh weather; it is part of our very nature. In the temperate, mostly stable climate of the past 10,000 years, we have grown accustomed to large and small adaptations. We’ve internalized expected climate extremes in our behavior and practice. We have seen industry and policy changes when we’ve experienced new extremes; for example, stronger building codes on the South Florida coast following Hurricane Andrew .

These two facts — that we can live in extreme conditions and that we have innate experience in managing our exposure to climate – establish (in me) some confidence in our capacity to cope with the coming changes.

But let’s not get ahead of ourselves. Though the climate of Earth will be habitable in 2100, we will be experiencing new extremes. Each decade will be different from the previous and next decade. The climate future could be quite bleak.

What to expect

Ecosystems and our relationships with ecosystems will continue to change, creating even more insecurity on the planet. Whole populations will be forced to relocate, and agricultural regions will shift according to available resources. Our building practices and engineering specifications will have to evolve.

The flaw in the message

Lowering emissions is critical to avoid the “worst effects” of global warming, according to the IPCC. (Image: iStock.)

As the climate changes, it is the human response that will either safeguard or imperil the planet’s future habitability. In 2007, Al Gore and the IPCC won the Nobel Prize for Peace for their efforts to bring these issues to the world’s attention so we could anticipate and prepare for this change.

And I must point out the IPCC report cited by my radio interviewer does not say all will be lost in a decade if humans don’t get a handle on our carbon dioxide emissions.

The report stated that by 2030 emissions need to be below 2010 levels by certain percentages to meet 1.5 ° or 2.0 ° C warming goals. This is critical to avoid the “worst effects” of global warming.

There is no evidence we will meet those goals and we are fast approaching that increase of 1.5 ° C. Are we, then, condemned to “the worst effects?”

The false choice

In the futuristic film ‘Waterworld,’ the polar ice cap has completely melted and the sea level has risen over 25,000 feet, covering nearly all of the land. (Universal Pictures, 1995.)

Here is the problem with that argument. It places our very existence in balance: “Meet this goal or climate will be an existential threat.” It also wrongly suggests that if we meet the goal, we will have avoided dangerous climate change. Problem solved. This is not true.

The 2030 goal is part of a process similar to “ flattening the curve ” during the COVID-19 pandemic. Just as in our responses to COVID-19, if we fail to meet the 2030 goal, we are making the problem worse. We are committing to a more difficult path and more damage, including loss of life. From a mitigation perspective , we will need to continue to reduce greenhouse gas emissions in the decades following 2030. Drastically.

More importantly, this “do-or-die” message diminishes the serious attention we should be paying to adaptation . We already have experienced and are committed to more warming. And we must develop a more systematic and anticipatory approach to extreme storms, fires, droughts, and floods. Today’s decisions regarding adaptation and mitigation will influence the quality of life for decades to come.

There is a more subtle communication element at work too. Though the emissions curve for carbon dioxide is relentlessly increasing, we have, in fact, avoided significant emissions. This is due to improved energy efficiency and growth in nuclear, wind, and solar energy. We’ve also increasingly transitioned from coal to natural gas to produce electricity. So, while the chatter in the public discourse is that we have “done nothing” to meet the 2030 goal, that is far from the truth.

Still, there is an urgency right now to reduce emissions further and take more drastic action. If we don’t, the moves we make between now and 2100 will become riskier, more difficult, and more expensive. The more slowly we reduce emissions, the more bleak 2100 becomes.

It never has been easy

Framing climate change in a semblance of realism is most important. This way, people can see what needs to be done and place themselves in personal, professional, and political positions to face the challenges it brings. As individuals, we need to broadcast effective influence so that more of us can understand, anticipate, and address future problems.

It won’t be easy. Never has it been so true that our here-and-now behavior will so directly impact the next hundred years. Never has it been so critical to revisit and adapt our decisions on a personal and societal level. Never has it been so true that we need a global and holistic approach to humanity’s choices and actions.

Climate change is a hard, wicked problem. But it is in the capacity of human ingenuity to anticipate, to address, and to thrive.

(Lead image from the Paramount Classics documentary “An Inconvenient Truth,” 2006.)

Joe Golonka - 1989

Thank you, Professor Rood, for cutting through the simplistic and too-often ideologically driven chatter that so often characterizes the climate change debate. False choices as well as improper framing and projection too often render an objective and solution driven discussion of this critical subject as difficult and even frustrating.

Although an evidence-based approach is foundational to science as well as most other other disciplines, our early 21st Century culture seems fraught with flawed premises as well as minimal efforts to discern actual evidence or to apply critical thinking. It is unrealistic to expect media talking heads and others whose existence depends on agendas of misinformation to change their approach. Despite this, I do remain optimistic that a partnership of the scientific community and thoughtful political leadership will ultimately lead to a sustainable outcome for our species.

Joe Golonka

Richard Rood

thanks for reading and writing, and I am glad you thought the piece did “cut through” some of the muck.

I am optimistic that there will be some pockets of thoughtful political leadership. and hopefully, they will tilt things in the right direction.

Rod Dumas - 16

Thank God for Joe Biden! He is at least a start But it will take others to have the stones to carry on. It is the ultimate question whether man is good or bad! It may be decided in our lifetime!

Darrin Cummings - 2012

I wouldn’t say “thank god for Biden”… but I am appreciative of his efforts for fighting climate change though they are little. Better then his predecessor!

tracy everitt - none

Humans , all of us, are afraid to face the obvious, certain outcome…we prefer to accentuate the positive… Personally have always felt that the earth will suddenly close down on us all…She behaves behaves, not as human scientists predict…and she always has been hurt by us humans, far worse than we admit…she is dying, quickly!…I give us 5 years before water wars, famine, devastations from climate disasters, and all those things are pushing nations into the madness of mob behavior, a madness which will finally cause a nucellar war, kill us all.

Brian Herberger - 1988

I have long wondered under the best of conditions, say we clean up our act in monumental ways (totally intended), how many people can this planet support? What is the estimated population in 2100 baring global castophre? Floating cities would have to be reality it seems to me. I don’t think humans are stupid for using natural resources, emitting carbons, burning fossil fuels, but it has consequences and resources run out. I’m just a high school/military educated guy in his 50s, but seems to me the planet will be just fine, not so sure about us however.

Michael Miller - 12

Your writing was found to be closer to reality than many will admit to. I personally am effected by the thinking that has pushed the automotive building to the point of no more gasoline powered vehicles I just don’t understand how we’re going to get there at the rate of the mining the elements required to build the batteries or chargers needed I feel like we need to develop hydrogen power safe enough for the average joe I also believe we need clean nuclear energy as the sun doesn’t always shine and wind doesn’t always blow that said I guess we will find out thank you for your articlee

Russell Wyndham

Human hubris causes us to believe that we are far more powerful/influential than we really are. Earth will be alive and thriving for many thousands or millions of years to come.

Jay Itay - 2016

I think it a far better example of human hubris that you think nothing will happen to us. I don’t doubt the earth will be alive and thriving in any segment of time. What I doubt is that human society wont fall well before that, as resources become scarce and livable land fails to support our numbers.

Just because life will still exist on earth doesn’t mean it will be a pleasant place for us to live. I’m no expert, but what is being said in this entry is not “we’ll be fine”. It’s “we should probably do something or there will be consequences. Maybe not as bad as extinction, and certainly not in the next 10 years, but no walk in the park either”.

Yves Le Goff - 1987

Among the more targeted questions, one seems worth adding: How soon will our civilization collapse? E.g. 2040 per revised MIT LtG model.

Human beings, taken as a whole, are ignorant, stupid, short-sighted, selfish, greedy, lazy and indifferent to the suffering of others. These shortcomings will be the end of us. If we followed the advice of environmentalists and climate scientists, we might just be able to take the measures necessary to avert partial or complete extinction, but we are in the hands of politicians who generally see no more than four or five years ahead and for whom there is always another, more urgent problem. We need to plan 25, 50 and 100 years ahead to stand any chance and there needs to be a huge redistribution of wealth and technology from rich countries to poorer ones. Anyone who doubts that the path civilization is on leads to extinction should read ‘The Uninhabitable Earth’ by David Wallace Wells. Perhaps the USA will wake up when Florida goes under water, but by then it will be too late.

Ro Dumas - 1970

…..just without us!!!

I agree with pretty much every thing you said John. I don’t think politicians or we as a society can “fix” the problem. Seems to me things are just headed towards their natural conclusion. Maybe we can slow it down, but we all know reality is Mother Nature and this planet are not within our control.

Martha Johnson - B.A., Univ. of Pa.

Professor Rood said that doomsday predictions are unnecessary. He stressed human adaptability and ingenuity. His point was that we need scientific and political changes now, or very soon, to avoid the worst effects of climate change: parts of the earth becoming uninhabitable, segments of the population dying.

I found Professor Rood’s piece reassuring. Based on his clear commentary, we can put away the nonsense, roll up our sleeves and get to work. I will write all of my representatives about the need for rapid climate action, and help others to do the same.

Patrick Boucher

Yes, many humans will adapt but can the same be said for the rest of the animal world? How many will decrease or face extinction? What effect will any these groups have on the larger picture? We claim to be “at the top” but we are not living in a homeostatic relation to the environment. Yes the media led many, including c’est moi, to believe inhabitability was inevitable. But we must be cautious. The effects bring felt are delayed. As Al Gore’s excellent movie implies climate change started with the Industrial Revolution when pollution started ona massive scaleand mother nature started coughing. We started producing more waste than could be removed. We started an imbalance. We still must do all we can to eradicate, not only reduce/adapt for future of animal kingdom which is defined as all living entities. We started the fire!

Sheila Wall, MD - 1983

Thank you! As a woman who grew up during the Cold War, I think more balanced views on climate change will motivate people more than doom and gloom which creates hopelessness and depression. Until recently, there wasn’t a lot a single person could do. There isn’t a lot now, but there is some. But what has been done has been marginally effective and points toward greater accomplishments in the future. My most recent visit to LA was in 2022. My previous visit had been in 1986. The effect that the climate changes made thus far are impressive. In 1986, driving into LA from anywhere meant observing increasing air pollution—in places there was so much that one couldn’t see more than 20’ ahead. In 2022, the air, even downtown, was remarkably better—and this had been due primarily to tough emission standards and laws. So changes can work. I suggest, though, that Democratic votes in the future are more likely to sustain current successes and allow for more!

Monica Young - 1998

Just “follow the science”, people. 😏

How The World Will Look in 2100. Here’s What Scientists Think

The world in 2100? How will it be? Can you imagine it? In the past, when thinking about the future, people used to imagine flying cars and cities in the sky, but is it the same now? Another theory that was popular in the 1990s was that we would live underwater, and instead of cities in the sky, we would have them deep in the ocean.

But as time passed and technology advanced, we became more aware of our limitations. This can help us predict the way our future will look in a more realistic manner. Also, technology will never stop evolving, which means we will have even more possibilities than we can imagine when we think about the world in 2100.

Read on and discover some theories about how the world will look in 2100. What do you think about them? Does the future seem brighter?

1. Virtual realities that are hyper-personalized

You’ve probably heard about the metaverse, but this concept belongs to 2023, not 2100. Companies presented the world with what these virtual worlds could be, and certain demographics were excited about it, but this is just the beginning.

What you see and understand today through the metaverse is something simple. This is the start of the next big thing that will take over the world. Take a second and try to imagine what virtual reality could be if it could gather all the information it needs directly from our brains. We know, we know, this might sound scary, but listen to us.

It would be incredible to have a world where everything is shaped according to your fantasies and can fulfill every dream of yours. People will be the kings and queens of their reality, and they will never get bored. This could be the ultimate entertainment machine.

On the other hand, virtual realities can become dangerous, and there are even some countries that consider using them as punishment for criminals. A reality like this can manifest a person’s biggest fears, and this is just scary.

2. Our cities will transform

The world in 2100 will be so much different than the world we have today. And this means cities are also included. It is obvious that since everything changes, they will not remain the same. The new cities will adapt to the new needs of humanity.

Let’s take a look at environmental problems and the way we manage our resources. It is clear that things don’t look so good, and future cities will need to adapt to this. That’s how arcologies will be born. These are massive structures that can encapsulate an entire city. These towers will be the largest structures ever built by humanity.

All the engineering behind these structures will be about carbon nanotubes that are able to sustain them. Since they are so big, the arcologies will be immune to earthquakes and other natural disasters.

So, cities will move into these massive towers, and there, humanity will have everything it needs: transportation, food, and social interaction. All of it will be condensed inside the arcologies.

3. The force fields

The world in 2100 will have many new technologies, and force fields will become a reality. But what are the force fields? More technologies that will be stacked together will create this new invisible protective shield. When it is activated, it will provide an almost impenetrable field that can take hits from almost any type of weapon.

An electromagnetic field-shaped dome or sphere made of supercharged plasma makes up the outer layer. This is hot enough to evaporate the majority of metals that come into contact with it. The secondary layer will have millions of laser beams that are able to catch and destroy the projectiles that are powerful enough to pass through the first layer.

The third layer will be composed of millions of nanotubes. And will be like a base that is able to hold the first two layers. The fourth and final layer will be made of photochromatic particles, and it will take care of the laser attack since it will be able to neutralize the laser beams.

So, the main purpose of this force will be protection. But besides protecting our planet, they will be used to create some of the strongest armor ever created and also to protect the satellites we have in space from any potential projectile that can hit them.

4. Knowledge and skill will be downloaded into our brains

How easy could it be to just want to learn a skill and then immediately drown it in your brain? We know it might sound a little bit farfetched, but this might be possible in the future. The world in 2100 will have technologies that will be so advanced that we can’t even think about them now.

At some point, humans will be able to connect the brain to software. This will basically give us access to our brains through an external device. And by being able to do this, we will also be able to download skills into our brains.

When knowledge is downloaded, the memory and planning centers of the brain rapidly incorporate it. This enables people to master subjects like computer technology or chemistry without needing to study or pick up a textbook.

Using this technology, humans will become more intelligent because, besides learning traditional skills, they will also be able to learn problem-solving, pattern recognition, critical thinking, or simply increase their vocabulary.

This technology might create conflict between people because some will not want to accept it. In the end, the computerized brains will be so much stronger than the non-altered ones, and we will see what happens from this point on.

5. Hive mind and telepathy

The world in 2100 will be a totally different place. What we know today will be long gone, and all of the new technologies will take the place of the ones that are familiar to us.

In the year 2100, it will be possible for people to connect to a worldwide network. The ideas of billions of people will be available for anyone to access. The global mind, the hive mind, and the brainternet are some of the titles given to this concept. You’ve probably already heard of it, but now it will be a reality.

Large groups of individuals may work together so much better, and it is easier than ever to accomplish time-sensitive goals. This idea is being adopted by businesses, nonprofits, and political organizations to enable better-structured work.

Also, it will be possible to access the emotions, feelings, and memories of other people and experience them anywhere and anytime you want.

Further, telepathic communication between people will be possible because of this kind of human advancement. We will be able to quickly communicate our ideas, fantasies, and feelings to others who have access to such knowledge.

As you can see, the world in 2100 will be completely new. The thing is that these changes will not happen immediately. They will take time, and humanity will be able to adapt to them.

What do you think? Do you feel ready to live in the future? Tell us your thoughts in the comment section!

If you are curious to see other theories about the future of the world, you can start with this book: The World in 2050: Four Forces Shaping Civilization’s Northern Future

You should also read: 9 Cities That Could Disappear by 2030

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Regions & Countries

World’s population is projected to nearly stop growing by the end of the century.

World population growth is projected to flatten in coming decades

For the first time in modern history, the world’s population is expected to virtually stop growing by the end of this century, due in large part to falling global fertility rates, according to a Pew Research Center analysis of new data from the United Nations .

By 2100, the world’s population is projected to reach approximately 10.9 billion, with annual growth of less than 0.1% – a steep decline from the current rate. Between 1950 and today, the world’s population grew between 1% and 2% each year, with the number of people rising from 2.5 billion to more than 7.7 billion.

Here are 11 key takeaways from the UN’s “ World Population Prospects 2019 ”:

The global fertility rate is expected to be 1.9 births per woman by 2100, down from 2.5 today. The rate is projected to fall below the replacement fertility rate (2.1 births per woman) by 2070. The replacement fertility rate is the number of births per woman needed to maintain a population’s size.

Global fertility is falling as the world is aging

The world’s median age is expected to increase to 42 in 2100, up from the current 31 – and from 24 in 1950. Between 2020 and 2100, the number of people ages 80 and older is expected to increase from 146 million to 881 million. Starting in 2073, there are projected to be more people ages 65 and older than under age 15 – the first time this will be the case. Contributing factors to the rise in the median age are the increase in life expectancy and falling fertility rates.

Africa is the only world region projected to have strong population growth for the rest of this century. Between 2020 and 2100, Africa’s population is expected to increase from 1.3 billion to 4.3 billion. Projections show these gains will come mostly in sub-Saharan Africa, which is expected to more than triple in population by 2100. The regions that include the United States and Canada (Northern America) and Australia and New Zealand (Oceania) are projected to grow throughout the rest of the century, too, but at slower rates than Africa. (This analysis uses regional classifications from the UN and may differ from other Pew Research Center reports.)

Population growth in Africa is projected to remain strong throughout this century

Europe and Latin America are both expected to have declining populations by 2100. Europe’s population is projected to peak at 748 million in 2021. The Latin America and Caribbean region is expected to surpass Europe in population by 2037 before peaking at 768 million in 2058.

The population of Asia is expected to increase from 4.6 billion in 2020 to 5.3 billion in 2055, then start to decline. China’s population is expected to peak in 2031, while the populations of Japan and South Korea are projected to decline after 2020. India’s population is expected to grow until 2059, when it will reach 1.7 billion. Meanwhile, Indonesia – the most populous country in Southeastern Asia – is projected to reach its peak population in 2067.

In the Northern America region, migration from the rest of the world is expected to be the primary driver of continued population growth. The immigrant population in the United States is expected to see a net increase of 85 million over the next 80 years (2020 to 2100) according to the UN projections, roughly equal to the total of the next nine highest countries combined. In Canada, migration is likely to be a key driver of growth, as Canadian deaths are expected to outnumber births.

By 2100, five of the world's 10 largest countries are projected to be in Africa

Six countries are projected to account for more than half of the world’s population growth through the end of this century, and five are in Africa. The global population is expected to grow by about 3.1 billion people between 2020 and 2100. More than half of this increase is projected to come from Nigeria, the Democratic Republic of the Congo, Tanzania, Ethiopia and Angola, along with one non-African country (Pakistan). Five African countries are projected to be in the world’s top 10 countries by population by 2100.

India is projected to surpass China as the world’s most populous country by 2027. Meanwhile, Nigeria will surpass the U.S. as the third-largest country in the world in 2047, according to the projections.

Between 2020 and 2100, 90 countries are expected to lose population. Two-thirds of all countries and territories in Europe (32 of 48) are expected to lose population by 2100. In Latin America and the Caribbean, half of the region’s 50 countries’ populations are expected to shrink. Between 1950 and 2020, by contrast, only six countries in the world lost population, due to much higher fertility rates and a relatively younger population in past decades.

By 2100, half of babies born worldwide are expected to be born in Africa

Africa is projected to overtake Asia in births by 2060. Half of babies born worldwide are expected to be born in Africa by 2100, up from three-in-ten today. Nigeria is expected to have 864 million births between 2020 and 2100, the most of any African country. The number of births in Nigeria is projected to exceed those in China by 2070.

Meanwhile, roughly a third of the world’s babies are projected to be born in Asia by the end of this century, down from about half today and from a peak of 65% in the 1965-70 period.

The Latin America and Caribbean region is expected to have the oldest population of any world region by 2100, a reversal from the 20th century. In 1950, the region’s median age was just 20 years. That figure is projected to more than double to 49 years by 2100.

Latin America and the Caribbean had one of the world's youngest populations in 1950; by 2100, it is expected to have the world's oldest

This pattern is evident when looking at individual countries in the region. For example, in 2020, the median ages of Brazil (33), Argentina (32) and Mexico (29) are all expected to be lower than the median age in the U.S. (38). However, by 2100, all three of these Latin American nations are projected to be older than the U.S. The median age will be 51 in Brazil, 49 in Mexico and 47 in Argentina, compared with a median age of 45 in the U.S. Colombia is expected to undergo a particularly stark transition, with its median age more than tripling between 1965 and 2100 – from 16 to 52.

Japan is projected to have the highest median age of any country in the world in 2020, at 48 years old. Japan’s median age is expected to continue to rise until it peaks at 55 in 2065. It is expected to be lower in 2100 (54). By that time, the country with the highest median age is expected to be Albania, with a median age of 61.

Correction: This post has been updated to clarify that India is expected to become the world’s most populous country by 2027. By 2059, its population is projected to peak at 1.7 billion.

Note: The UN projections for the future population are based on assumptions about likely future changes in key demographic indicators, including fertility, life expectancy and migration. There is uncertainty regarding specific estimates. This analysis uses the medium variant for future dates, which takes the midpoint of likely outcomes. For more information, see the full UN report, data tables and methodology .

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About Pew Research Center Pew Research Center is a nonpartisan fact tank that informs the public about the issues, attitudes and trends shaping the world. It conducts public opinion polling, demographic research, media content analysis and other empirical social science research. Pew Research Center does not take policy positions. It is a subsidiary of The Pew Charitable Trusts .

Earth, 2100 AD: Four futures of environment and society

Climate models and the latest IPCC data reveal four possible futures for global population, economy and environment at the end of this century

By Catherine Brahic

3 October 2013

How different will it look at the end of this century?

(Image: Superstock)

YOU may have heard last week that Earth in 2100 is likely to be between 0.3 and 4.8 °C warmer than it was in the late 20th century. This is one of the key messages of the latest UN Intergovernmental Panel on Climate Change report. Why such a broad range? Because the rise in temperature depends largely on what we choose to do now – where our energy and food come from, the type of buildings we live in and the cars we drive. And of course, how many people populate the planet.

Read more: “ IPCC 2013: The latest state of the climate report “

Those choices will determine whether Earth stays much the same as it is today, or if rising seas eat up major land masses – Florida , Bangladesh, we’re looking at you – and large parts of the world become too dry to live in (see diagram).

Climate scientists combine the various options into descriptions of how human society might evolve, and plug them into their models to see what each scenario would mean for the climate. For ease of comparison, they have agreed on two extreme scenarios and a couple in between. That is what determines the 0.3 to 4.8 °C range.

It is important to stress that these are just four of the many possible scenarios and ways to cut emissions. But we feel the value of the exercise is in showing how much of the outcome is still in our hands and down to the choices and trade-offs we make as individuals and as society as a whole. For example, a low population opens some options. A high one closes others down, but you could compensate for that by transforming the transport sector, for instance.

Editorial: “ The future of the climate is still in our hands “

“We want people to think about what world they want to live in, and then think about ways that they can make that consistent with a climate future that they want,” says Richard Moss of the Pacific Northwest National Laboratory in Richland, Washington, who has been closely involved in developing the climate scenarios.

“We want people to think about what sort of world they want to live in”

1: Geoengineered safety

Population 9 billion Global energy use 8 × 10 20 joules CO 2 concentration 400 ppm, dropping

We acted early in the 21st century, invested aggressively in renewable energies and crucially, geoengineering

It wasn’t easy, but by investing heavily in R&D, we have built systems for sucking carbon dioxide out of the atmosphere and storing it underground. At the same time, we have invested in renewable energies and virtually weaned ourselves off fossil fuels. The net result: annual carbon emissions have plummeted, and atmospheric concentrations of CO 2 are finally dropping.

Crucial to making this happen was the spread of bioenergy power plants coupled to carbon storage facilities – a soft form of geoengineering. We grew trees and plants to burn and produce electricity. They suck CO 2 out of the atmosphere as they grow. We captured the greenhouse gases produced when we burn trees, and put the gases in geological seams deep underground – where they will stay for centuries or more.

Global temperatures have held steady since 2050. We’ve also halted the decline of sea ice in the Arctic and slowed ocean acidification. Sea levels are still rising, though, because of heat stored in the system from earlier emissions.

2: Slight delay

Population 8.5 billion Global energy use 1 × 10 21 joules CO 2 concentration stable at 550 ppm

We delayed both the transition to renewable energies, and the implementation of climate treaties

As a whole, we are a more efficient society than in 2013, using less energy and fewer materials to produce more. We are also good recyclers. All of this makes for better management of natural resources. Earlier on in the century, gas was the transition fuel of choice. Now most of our energy comes from renewables and nuclear. Incentives and better international institutions mean green technologies spread rapidly. We have made the transition to a low-carbon economy. We eat far less meat than in 2013, to cut the emissions generated by livestock farming. So pastures have shrunk and agriculture is more efficient. Forests are growing, boosting the amount of CO 2 stored in trees around the world.

We live in compact cities with excellent public transport which also limits emissions. Although temperatures and sea levels have risen, some of the more extreme consequences of climate change haven’t come to pass.

3: Too little, too late

Population 9.5 billion Global energy use 8 × 10 20 joules CO 2 concentration 650 ppm and rising

We cut emissions, but not until late in the century

The first half of the century was spent mostly carrying on business as usual: we relied heavily on fossil fuels. We did not introduce any dramatic changes to our life styles or activities in terms of consumption, travel and the number of children we have. Then, towards the middle of the century, the consequences of climate change became too difficult to ignore. As a result, our governments slowly began introducing some unambitious policies to regulate emissions.

We are now slowly making our way towards a green energy supply. Oil consumption started to drop a few decades ago, but 75 per cent of our energy still comes from fossil fuels, not much less than the 82 per cent in 2011.

Because of our inaction, temperatures are still rising, as are sea levels. Models suggest they will continue doing so for several decades more.

4: Addicted to carbon

Population 12.5 billion Global energy use 1.75 × 10 21 joules CO 2 concentration 950 ppm and rising

The world economy is booming, but it’s fuelled by coal and oil. The global population continued to grow rapidly throughout the century, pushing emissions ever higher

Welcome to the globalised, high-tech, consumerist future: one where we are still hooked on fossil fuels. Emissions have gone through the roof, and human health and the environment are the casualties. Biodiversity crashes are threatening the normal operation of “ecosystem services” – natural processes such as water recycling through rain and rivers, and pollination.

Most of our energy still comes from fossil fuels, including from unconventional sources, like methane clathrates, tar sands, and fracked shale-gas deposits. Coal is still on the menu. We haven’t invested significantly in alternative energies. Globally, we also eat more meat and dairy products than we did in 2013.

Consequently, emissions and temperatures are still rising fast. Droughts and floods are more frequent and claiming more and more lives. Ocean acidification is severe, and getting worse. The Arctic has not had ice during the summer for several decades.

This article appeared in print under the headline “Pictures of Earth 2100”

Correction: When this article was first published on 3 October 2013, the figures for global energy use in the four scenarios were mistakenly formatted without superscripts.

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The origin of life on Earth, explained

The origin of life on Earth stands as one of the great mysteries of science. Various answers have been proposed, all of which remain unverified. To find out if we are alone in the galaxy, we will need to better understand what geochemical conditions nurtured the first life forms. What water, chemistry and temperature cycles fostered the chemical reactions that allowed life to emerge on our planet? Because life arose in the largely unknown surface conditions of Earth’s early history, answering these and other questions remains a challenge.

Several seminal experiments in this topic have been conducted at the University of Chicago, including the Miller-Urey experiment that suggested how the building blocks of life could form in a primordial soup.

Jump to a section:

When did life on Earth begin?

Where did life on Earth begin?

What are the ingredients of life on earth, what are the major scientific theories for how life emerged, what is chirality and why is it biologically important, what research are uchicago scientists currently conducting on the origins of life, when did life on earth begin .

Earth is about 4.5 billion years old. Scientists think that by 4.3 billion years ago, Earth may have developed conditions suitable to support life. The oldest known fossils, however, are only 3.7 billion years old. During that 600 million-year window, life may have emerged repeatedly, only to be snuffed out by catastrophic collisions with asteroids and comets.

The details of those early events are not well preserved in Earth’s oldest rocks. Some hints come from the oldest zircons, highly durable minerals that formed in magma. Scientists have found traces of a form of carbon—an important element in living organisms— in one such 4.1 billion-year-old zircon . However, it does not provide enough evidence to prove life’s existence at that early date.

Two possibilities are in volcanically active hydrothermal environments on land and at sea.

Some microorganisms thrive in the scalding, highly acidic hot springs environments like those found today in Iceland, Norway and Yellowstone National Park. The same goes for deep-sea hydrothermal vents. These chimney-like vents form where seawater comes into contact with magma on the ocean floor, resulting in streams of superheated plumes. The microorganisms that live near such plumes have led some scientists to suggest them as the birthplaces of Earth’s first life forms.

Organic molecules may also have formed in certain types of clay minerals that could have offered favorable conditions for protection and preservation. This could have happened on Earth during its early history, or on comets and asteroids that later brought them to Earth in collisions. This would suggest that the same process could have seeded life on planets elsewhere in the universe.

The recipe consists of a steady energy source, organic compounds and water.

Sunlight provides the energy source at the surface, which drives photosynthesis. On the ocean floor, geothermal energy supplies the chemical nutrients that organisms need to live.

Also crucial are the elements important to life . For us, these are carbon, hydrogen, oxygen, nitrogen, and phosphorus. But there are several scientific mysteries about how these elements wound up together on Earth. For example, scientists would not expect a planet that formed so close to the sun to naturally incorporate carbon and nitrogen. These elements become solid only under very cold temperatures, such as exist in the outer solar system, not nearer to the sun where Earth is. Also, carbon, like gold, is rare at the Earth’s surface. That’s because carbon chemically bonds more often with iron than rock. Gold also bonds more often with metal, so most of it ends up in the Earth’s core. So, how did the small amounts found at the surface get there? Could a similar process also have unfolded on other planets?

The last ingredient is water. Water now covers about 70% of Earth’s surface, but how much sat on the surface 4 billion years ago? Like carbon and nitrogen, water is much more likely to become a part of solid objects that formed at a greater distance from the sun. To explain its presence on Earth, one theory proposes that a class of meteorites called carbonaceous chondrites formed far enough from the sun to have served as a water-delivery system.

There are several theories for how life came to be on Earth. These include:

Life emerged from a primordial soup

As a University of Chicago graduate student in 1952, Stanley Miller performed a famous experiment with Harold Urey, a Nobel laureate in chemistry. Their results explored the idea that life formed in a primordial soup.

Miller and Urey injected ammonia, methane and water vapor into an enclosed glass container to simulate what were then believed to be the conditions of Earth’s early atmosphere. Then they passed electrical sparks through the container to simulate lightning. Amino acids, the building blocks of proteins, soon formed. Miller and Urey realized that this process could have paved the way for the molecules needed to produce life.

Scientists now believe that Earth’s early atmosphere had a different chemical makeup from Miller and Urey’s recipe. Even so, the experiment gave rise to a new scientific field called prebiotic or abiotic chemistry, the chemistry that preceded the origin of life. This is the opposite of biogenesis, the idea that only a living organism can beget another living organism.

Seeded by comets or meteors

Some scientists think that some of the molecules important to life may be produced outside the Earth. Instead, they suggest that these ingredients came from meteorites or comets.

“A colleague once told me, ‘It’s a lot easier to build a house out of Legos when they’re falling from the sky,’” said Fred Ciesla, a geophysical sciences professor at UChicago. Ciesla and that colleague, Scott Sandford of the NASA Ames Research Center, published research showing that complex organic compounds were readily produced under conditions that likely prevailed in the early solar system when many meteorites formed.

Meteorites then might have served as the cosmic Mayflowers that transported molecular seeds to Earth. In 1969, the Murchison meteorite that fell in Australia contained dozens of different amino acids—the building blocks of life.

Comets may also have offered a ride to Earth-bound hitchhiking molecules, according to experimental results published in 2001 by a team of researchers from Argonne National Laboratory, the University of California Berkeley, and Lawrence Berkeley National Laboratory. By showing that amino acids could survive a fiery comet collision with Earth, the team bolstered the idea that life’s raw materials came from space.

In 2019, a team of researchers in France and Italy reported finding extraterrestrial organic material preserved in the 3.3 billion-year-old sediments of Barberton, South Africa. The team suggested micrometeorites as the material’s likely source. Further such evidence came in 2022 from samples of asteroid Ryugu returned to Earth by Japan’s Hayabusa2 mission. The count of amino acids found in the Ryugu samples now exceeds 20 different types .

In 1953, UChicago researchers published a landmark paper in the Journal of Biological Chemistry that marked the discovery of the pro-chirality concept , which pervades modern chemistry and biology. The paper described an experiment showing that the chirality of molecules—or “handedness,” much the way the right and left hands differ from one another—drives all life processes. Without chirality, large biological molecules such as proteins would be unable to form structures that could be reproduced.

Today, research on the origin of life at UChicago is expanding. As scientists have been able to find more and more exoplanets—that is, planets around stars elsewhere in the galaxy—the question of what the essential ingredients for life are and how to look for signs of them has heated up.

Nobel laureate Jack Szostak joined the UChicago faculty as University Professor in Chemistry in 2022 and will lead the University’s new interdisciplinary Origins of Life Initiative to coordinate research efforts into the origin of life on Earth. Scientists from several departments of the Physical Sciences Division are joining the initiative, including specialists in chemistry, astronomy, geology and geophysics.

“Right now we are getting truly unprecedented amounts of data coming in: Missions like Hayabusa and OSIRIS-REx are bringing us pieces of asteroids, which helps us understand the conditions that form planets, and NASA’s new JWST telescope is taking astounding data on the solar system and the planets around us ,” said Prof. Ciesla. “I think we’re going to make huge progress on this question.”

Last updated Sept. 19, 2022.

Faculty Experts

Clara Blättler

Fred Ciesla

Jack Szostak

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NEWS FEATURE
22 April 2020

How hot will Earth get by 2100?

Jeff Tollefson

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As world leaders gathered to mark the start of 2050, they looked back on the coronavirus pandemic 30 years before as a turning point in the quest to rein in global warming. Nations pulled together to defeat the pandemic, and that launched a new era of cooperation to prevent a climate disaster. Investments in green energy and new technology yielded rapid cuts in emissions of carbon dioxide, putting the world on track to limit global warming to around 1.5 °C above pre-industrial levels.

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Nature 580 , 443-445 (2020)

doi: https://doi.org/10.1038/d41586-020-01125-x

O’Neill, B. C. et al. Glob. Environ. Change 42 , 169–180 (2017).

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US Global Change Research Program. Fourth National Climate Assessment, Vols I–II (US Global Change Research Program, 2017–18).

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Intergovernmental Panel on Climate Change. Climate Change 2014: Synthesis Report. Contribution of Working Groups I, II and III to the Fifth Assessment Report of the Intergovernmental Panel on Climate Change (IPCC, 2014).

Moss, R. H. et al. Nature 463 , 747–756 (2010).

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Hausfather, Z. & Peters, G. P. Nature 577 , 618–620 (2020).

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Climate Change: What Happens after 2100?

We all know that the carbon legacy of our fossil fuel-based lifestyles is bequeathing a climate crisis to billions of people into the future. But when we say “future”, just how far should we be thinking ahead? As far as 2050? 2100? Or a little bit further, maybe as far as 2500 and beyond?

You may have already noticed that future climate projections used by the international scientific and political communities generally go only as far as the year 2100. The simple reason for this is that it is impossible to predict with any degree of accuracy just how much greenhouse gases are going to be released in the next few centuries, and just how much this is going to affect the climate.

But don’t be fooled. This does not mean that climate change will cease to be a problem in the years lying beyond the upper reach of our most cited climate forecasts. The shocking truth is that climate change has only just begun. Regardless of future emission trends, the CO2 footprint from our brief passage on Earth is going to remain in the climate system and impact the well-being of all terrestrial life forms for what could almost be considered an eternity.

The majority of C02 emitted from burning a single tonne of coal or oil today will be absorbed over a few centuries by the oceans and vegetation, the remaining 25% will still be affecting the climate in 1,000 years.

Photo: Strange Frontier .

According to scientist David Archer, whose research is often featured in the renowned Nature magazine, the C02 that we are emitting from fossil fuels today will still be affecting the climate in many millenia from now. His conclusion is that even though the majority of C02 emitted from burning a single tonne of coal or oil today will be absorbed over a few centuries by the oceans and vegetation, approximately 25% of it will still be lingering in the atmosphere in 1,000 years, and 10% still remaining and impacting the climate in 100,000 years time.

It will then require thousands and thousands more years for its complete absorption through the natural climate cycle. As Archer puts it, “the climatic impacts of releasing fossil fuel C02 to the atmosphere will last longer than Stonehenge, longer than time capsules, longer than nuclear waste”.

The Copenhagen Diagnosis

Some of this future devastation is briefly discussed in the recently updated Copenhagen Diagnosis — a report authored by 26 leading climate scientists with the aim of updating the world on findings since the publication of the IPCC Fourth Assessment Report in 2007. According to this Copenhagen Diagnosis, regardless of when a peak in global emissions finally occurs, the global temperature cannot be expected to stop rising until several centuries later, due to the extremely long life cycle of C02.

The carbon that we are releasing into the atmosphere today is in the process of ‘programming’ a potential 2-5 metres of sea level rise by around the year 2300.

But that’s not all. The report also states that “even a thousand years after reaching a zero-emission society, temperatures will remain elevated, likely cooling down by only a few tenths of a degree below their peak values.”

In other words, whatever the mitigation efforts of future civilisations, climate change is here to stay. Only after this extremely long period of forced warming — far more than the history of modern civilisation since the Scientific Revolution — will climate change slowly begin to ‘reverse’ and the planet will at last embark on a cooling trajectory, the report explains.

But long before this ever happens, humanity must prepare itself for an inland retreat and a constant battle against rising seawater that will continue for hundreds and hundreds of years into the future. The phenomenon of sea level rise resulting from thermal expansion (sea water expands as it warms) and melting ice sheets in Greenland and Antarctica is the perfect illustration of climate inertia in action.

As may be seen from the graph below, showing estimates from three different models, it takes several centuries for the oceans to fully respond to a warmer climate and altered carbon balance. As a result, the carbon that we are releasing into the atmosphere today is in the process of ‘programming’ a potential 2-5 metres of sea level rise by around the year 2300.

Source: Copenhagen Diagnosis .

What’s more, the authors of the Copenhagen Diagnosis warn that sea level rise will continue for many centuries after the eventual stabilisation of global temperature (and therefore beyond the upper limit of this graph too). This is no doubt going to have a devastating impact upon future cities, towns, agricultural areas and freshwater resources located near coastal regions. (The Centre for Remote Sensing of Ice Sheets has some detailed images available of the areas of the globe most threatened by sea level rise.)

Small decisions, huge consequences

With this geological mayhem scheduled to take place over the next several thousand years, the decisions that we are making (read: not making) in the present take on a new light. Clearly we need to expand the time scale with which we assess the full implications of the climate crisis beyond the current century. Once humans turn up the planetary thermostat by 2°C (the goal to which the international community is committed at present, albeit very optimistically), there will be no turning it back, save a trend towards planet-altering geo-engineering .

Instead, the temperature control will be locked in and all life forms on Earth will be pressured to adapt for thousands of years. The climate change-driven ecological destruction that we are witnessing today — immeasurable loss of human life, plant and animal species caused by natural disasters such as floods, droughts, wildfires and heat waves, the disappearance of vast snow caps, glaciers and almost half of the Arctic — is the result of a mere 0.8°C rise in average temperature since 1800. We can only imagine what a further 1.2°C rise before 2100 will mean for the Earth’s already vulnerable ecosystems and at-climate-risk communities.

Future ethics

The planet is the ultimate ‘global commons’. It belongs to neither a particular individual nor a particular nation. Nor does it belong to a single generation such as us, our children or our grandchildren. Instead, it belongs to all living creatures both alive now and in the future. Just as all of humanity is connected ‘horizontally’ across the globe, so too are all past and future life forms bound ‘vertically’ in a continual unfolding of the story of life.

Yet the political and economic institutions of our civilisation are fixated on enjoying the present and unable to account for the consequences of our actions on tomorrow. This may be all too easily observed in our financial behaviour, where individuals, corporations and governments are forever borrowing from the future in order to improve the present.

In the same way, the fossil fuelled party of our capitalist global civilisation is in the midst of a financial and ecological borrowing frenzy from the future. And not only are the spoils of our mastery over nature enjoyed by only a minority of the planet, but in geological terms, they are being consumed within an extremely short time-span.

In a crisis of modernity that could also be re-interpreted as one of ethics and values , how should we reframe our choices and actions in the present, in light of tomorrow?

Surely it is just a matter of standing in the shoes of all future citizens and asking ourselves what sort of planet they would like to live on. Surely our descendants, hundreds and thousands of years into the future, would wish for, and have a right to, the same stable climate and ocean levels that have allowed the attainment of such an advanced and flourishing civilisation today.

It is none other than this consideration for future human beings and other life forms that should form the yardstick by which we set our mitigation targets — not merely what is politically and economically feasible for the industrialised world today.

Gregory Trencher

Gregory Trencher was previously an intern for the Education for Sustainable Development Programme at UNU Institute of Advanced Studies in Yokohama, Japan. He is currently researching the potential of research universities to address the climate and sustainability crisis as part of a Ph.D. at the Graduate Programme in Sustainability Science at the University of Tokyo. He is also director of the Environmental Learning Institute , a climate change educational initiative for Japanese businesses and corporations.

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September 10, 2021

What will the planet look like in 50 years? Here's how climate scientists figure it out

by Margo Rosenbaum

Climate change scientists don't like to use the term "prediction." Rather, they're making "projections" about the future of the planet as sea levels rise, wildfires sweep the West and hurricanes become more ferocious.

There's a good reason for that.

In a world awash in misinformation—about medicine, politics and climate, and pretty much everything else—part of a scientist's job now involves teaching the public about how science works. Convincing the public to have faith in science means making precise, measured projects about the future.

They've got to overcome the big question: Can you really make accurate projections about what the planet will look like in 50 years, a century from now?

Climate scientists think they can, based on the past five decades of climate science that has proven accurate. Futurists, such as Jamais Cascio, a distinguished fellow for the Institute for the Future, a nonprofit foresight group based in Silicon Valley, study present trends and available data to lay out plausible outcomes for the future.

Today, a lot of Cascio's work is centered around climate change, helping people prepare for the future and make informed decisions for a warming world.

"Everything in the world," Cascio said, "every future outcome will have to be examined through the lens of climate."

In the future, climate change may only get worse. But how much worse will it get?

Scientists have relied on climate models for over 50 years. To people who aren't scientists, it's challenging to understand the calculations that go into these projections. So, what exactly is a climate model?

Meteorologists can make weather predictions for the next hour, or even week, based on weather data and forecast models that use humidity, temperature, air pressure, wind speed, among other current atmospheric, land and oceanic conditions. But with climate, a specific region's weather averaged over decades, is a little more challenging to project and understand.

An extension of weather forecasting, climate models factor in even more atmospheric, land and oceanic conditions to make longer-term forecasts. Using mathematical equations and thousands of data points, the models create representations of physical conditions on earth and simulations of the current climate.

Climate models predict how average conditions will change in a region over the coming decades as well as how the climate appeared before humans recorded it.

Researchers can then understand how these changing conditions could impact the planet, which is useful especially for understanding climate change, said Zeke Hausfather, a climate scientist and director of climate and energy at the Breakthrough Institute, an environmental research center based in the Bay Area.

"Perhaps the most important (purpose) is to try to suggest the types of changes that might occur as the world continues to emit CO2 and other greenhouse gases," Hausfather said.

The first climate model, developed over 50 years ago in the early days of climate science, helped scientists gauge how the ocean and atmosphere interacted with each other to influence the climate. The model predicted how temperature changes and shifts in ocean and atmospheric currents could lead to climate change.

Today, these models are much more complicated and run on some of the world's most powerful supercomputers. A decade ago, most models broke up the world into 250-kilometer segments, but now the models are 100 square kilometers. More regional patterns emerge when simulations are at a finer scale.

"People aren't drawing a picture of temperature and carbon dioxide and drawing a line through it and then extrapolating that into the future," said Gavin A. Schmidt, a senior climate adviser at NASA.

Through these advancements in technology, these models are becoming even more useful to scientists in understanding the climate of the past, present and future.

"Fortunately, they don't do such a terrible job," Schmidt said.

All of this works toward convincing the public and businesses to take action.

A majority of Americans already notice the effects of climate change around them, according to a Pew Research Center survey from 2020. But individuals, businesses and politics must "adapt to a radically and dangerously changing climate," Cascio said.

On the individual level, people must consider the climate in all of their monumental decisions: whether to have children; which car to buy; how to invest; when and where to buy a house. Governments are tasked with climate decisions that impact the future of entire nations, such as whether to invest in alternative energy or write policy curbing emissions.

Are climate models useful?

Instead of thinking about climate models as whether or not they are right, Schmidt said climate models should be considered as to whether they provide useful forecasts.

"Do they tell us things? Do they get things right more than you would have done without them?" Schmidt said.

Usually, the answer is yes, and what these models inform scientists is crucial for their understanding of the future climate.

Hausfather knows this better than anyone, as he led a study published in the journal Geophysical Research Letters analyzing the accuracy of early climate models. Some of the findings were included in the latest report from the United Nations' Intergovernmental Panel on Climate Change published in August.

Hausfather, along with co-author Schmidt, compared 17 model projections of global average temperature developed between 1970 and 2007 with actual changes in global temperature observed through the end of 2017.

Hausfather and his colleagues found promising news: Most of the models have been quite accurate. More specifically, 10 of the model projections show results consistent with observations. Of the remaining seven model projections, four projected more warming than observed while three projected less warming than observed.

But Hausfather and his colleagues realized this wasn't telling the whole story. After accounting for differences between modeled and actual changes in atmospheric carbon dioxide and other factors driving the climate, it turns out 14 of 17 model projections were "effectively identical" to warming observed in the real world.

"That was strong evidence that these models are effectively right," Hausfather said. "They're doing a very good job of predicting global temperatures."

The accuracy was particularly impressive in the earliest climate models, Hausfather said, especially given the limited observational evidence of warming at the time.

But not all of the early models were error-free. One of the first climate models, created in 1971 by climate scientists Rasool and Schneider, projected that the world would cool due to the cooling effect of atmospheric aerosols.

"(The researchers) thought that the cooling effect of these aerosols from burning fossil fuels that would reflect sunlight back to space would be much stronger than the warming effects of the greenhouse gas," Hausfather said.

While the 1970s were still in the early days of climate research, most of the scientific literature of the time was still pointing toward a warming future as much more likely. Yet, Rasool and Schneider's model still spurred a slew of news stories about a potential ice age. Even today, the model "still gets trotted out every now and then by folks trying to discredit climate science today," Hausfather said.

Now the model is proven to be wrong. It's a consensus among climate scientists that the planet is not cooling—instead it's warming at an alarming rate.

Even today, despite the promise of climate models shown by Hausfather's study, these models still have their limitations, especially with regard to the uncertainty of future emissions. Climate scientists are physicists—not economists or political scientists, and it's challenging to understand how policy will shape emissions standards.

"We don't have a crystal ball that can predict the future human behavior in terms of how much our emissions will change," Hausfather said. "We can just predict how the climate will respond to the emissions."

Issues of accuracy in climate models also still arise when models are pushed outside of their specific parameters. To combat this, climate models focus their projections on physical conditions seen in the natural world, instead of statistical probability, Schmidt said.

Researchers have more confidence in the predictability of physics than statistics, because physics doesn't change into the future. Researchers can have confidence that they can use these models outside of the time period where they have observational data, such as looking at climate during the last ice age, Schmidt said.

"How things get expressed might be different but the basic physics ... the underlying processes don't really change," Schmidt said.

Hausfather said there's still a lot of work still to improve climate models, but they are consistently getting better over time. Simulations of the Earth become sharper as more physical processes are added and computer power grows.

Why make projections for the future?

While climate scientists focus on physics to make forecasts for the future climate, Cascio and other futurists place scientific data in a larger context, making foresight based on climate change, new technological developments, as well as political and social movements. Futurism is "essentially anticipatory history," Cascio said.

"The idea is to take the science and embed it into a historian's understanding of how the world works to try to get a sense of what are the possible outcomes that we see going forward," Cascio said.

But, just like with climate models , uncertainty is inherent to the nature of projections. Futurists do not want to over-promise, but they provide a forecast of what could happen and reasons why it could happen, Cascio said.

Most of Cascio's work with climate change projects a grim future. In his perspective, an "absolutely radical" and "transformative" climate plan is necessary to make the necessary change. Plans that are "sensible and acceptable (are) almost definitely not enough."

"I really want to be wrong about all of this stuff," Cascio said, "because there are no futures that are not really depressing for the next generation."

Despite the despair projected by many climate scientists and futurists, there's still hope. If global emissions can be brought down to zero, Hausfather said the best climate model estimates illustrate that the world will stop warming.

"It's not too late to act," Hausfather said. "The world is not locked into a particular amount of warming."

Cascio still tries to consider himself a long-term optimist for the future, because the changes necessary to mitigate climate change will also lead to a much more "transparent and equitable" world, he said.

"If we can make it through the second half of this century, there's a very good chance that what we'll end up with is a really wonderful world," Cascio said.

Journal information: Geophysical Research Letters

Distributed by Tribune Content Agency, LLC.

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What will the world be like in 2100?

Let’s explore what the world will be like in 2100. who knows, you may still be alive to enjoy it.

Will you be alive in 2100?

Think about you in 2100.

Yeah, I know, it’s difficult.

That’s because we have difficulty relating to our future selves . The further into the future we look, the more of a stranger our future self is for us. 2100 is very far away, so it is almost impossible for us to visualize ourselves then and to feel empathy for that future us.

Also, most of us probably think we will not be alive anyway. It is too far away.

I will be 121 years old. Who lives to that age? Not many people nowadays, but people like Ray Kurzweil, who aims to live long enough, to live forever , think otherwise. Kurzweil and other techno-utopians believe that advances in biotechnology, genetics, and medicine will allow us to live much longer lives in good health, or even achieve some kind of a-mortality and never again die due to illness and old age.

I am not sure we’ll ever get there, but it is in the realm of possibility to increase our life expectancy by a few decades by the end of the century .

Another issue is if we, as a species, will still be around. The philosopher Toby Ord’s odds for the human species going extinct in this century are 1 in 6 , a simple roll of the dice. This probability is too high if you ask me, but still, it seems it is more likely than not that we will be around as a species.

So, we will probably exist, and there is the possibility that many of us will still be around in good health. What will the world be like in 2100?

It will be a hotter world, with more extreme weather

The world in 2100 will be hotter, with more extreme weather and more natural disasters such as hurricanes and wildfires.

How much hotter? It is impossible to know right now, as it will depend on our actions during the next 80 years.

There are different scenarios , from the world being 1.5ºC to 5ºC hotter by 2100 . There is a big difference between these two extremes, but note that even if we reduced all our carbon emissions to zero today, the world would still keep warming for decades due to all the extra carbon dioxide already in the atmosphere.

Our best-case scenario is a 1.5ºC increase (although some experts believe we will reach this already by 2030), which doesn’t seem much, but it is huge. Even with this best-case scenario, the sea levels will rise around 1 meter, displacing millions of people and forcing us to invest trillions of dollars in making our coastal cities and towns habitable.

In this best-case scenario, natural disasters, such as droughts, floods, hurricanes, and wildfires, will become more frequent and more intense . Global warming isn’t only about warming; it is also about having more extreme weather.

The worst-case scenario of a 5ºC increase seems to be far-fetched, but there is still the risk it may happen or that it may get close to it, which would be disastrous. Millions, if not billions, of people would die and big swats of Earth would be inhabitable.

Let’s try to avoid it, please. It is in our hands, but we need to start working towards it now.

A more populous world in 2100

Demographic projections are usually relatively accurate, as death and fertility rates don’t change drastically over time. However, the further into the future you go, the more chances there are that some of those rates will vary considerably, wreaking havoc in those projections.

Until recently, the consensus was that the world population would peak at around 11 billion people by the end of the century and then start shrinking as fertility rates go down. However, a more recent study projects a more rapid decrease in the fertility rate due to advances in women’s education and contraceptive use, with the world population peaking at around 9 billion people by 2100.

Whichever way you look at it, the world at the end of the century will be home to many more people , and it will be more densely populated, with higher pressure on resources and an already strained environment .

All projections agree that most of the growth will come from Africa, tripling its population to 4.3 billion based on the more widespread forecast. Asia would peak mid-century and then shrink but continue being the most populous region globally with 4.7 billion people.

This means Africa and Asia will be home to 9 out of the 11 billion human beings living on earth . This will have a considerable impact on the balance of power in global institutions and global markets, on the ways business is conducted, on the cultures having a more significant impact on the world, etc.

It is likely that Western ways of living and culture will take a back seat by the end of the century, if not much earlier.

A new World Order in 2100

What will be the World Order in 2100?

Will the US still be the world’s superpower? Or will China take its place? Will it be a bipolar world with a new Cold War? Will we have more globalization, or will we go back to further fragmentation and distance between countries?

Many things can and usually happen in geopolitics in 80 years, but it seems reasonable to think that the US and China will be the two superpowers dominating the world . How they get along between them is another matter.

As Kai-Fu Lee explained in AI Super-powers , AI will be the technology that will give power to countries, both economic and political, and China and the US are building an unassailable lead in this area. They are creating the necessary company ecosystems, and they have the data, the technology, and the talent to dominate the world of AI. The vast distance between them and the rest of the world will only grow with time.

Trump’s presidency, the dismal management of the Covid-19 crisis by different levels of the US government, the extreme polarization of its politics, and the recent overall retrenchment from the world seem to signal the decline of the US against an increasingly stronger and more assertive China, but this may be just a blip.

The US is still the most powerful country in the world in many areas, and I believe it will remain to be so for a while. Will that last until the end of the century? It is difficult to tell, but in some measure, it will also depend on what the rest of the world does and the alliances the US is able to maintain or win.

After the second world war, the US built a world order based on global or multi-country institutions like the UN, NATO, the IFM, or the World Bank and key alliances in all continents.

This Pax Americana has enabled the globalization of the economy (and society and culture), has increased global trade and has brought enormous prosperity to America but also to many other parts of the world. In the last few years, the US has taken a back seat and is retrenching from global institutions and somehow relinquishing its role as the world leader. I suspect this will damage the US interests the most, and they may reverse this trend, but if they don’t, it will be interesting to see what countries or regions fill the vacuum they will leave behind.

As I wrote last week , globalization is receding, and the world is generally becoming more nationalistic and vocalist.

I think this is a short-term swing of the pendulum in the direction of de-globalization, but the general trend seems to be toward further integration. I think we will reach the end of the century with more regional blocs, a more global collaboration to solve global problems, and a more prominent role of international institutions.

I hope the world will become smaller, closer, and more integrated, not more fragmented and parochial . And I pray that there isn’t a big war between big countries or regions, because then we may not even reach the year 2100.

The age of technological marvels

Technology has been a significant engine of change in the last few decades.

We are entering an Exponential Age with technological breakthroughs advancing at an increasing pace, so in the next 80 years, there will be advances that we cannot even imagine today .

It is reasonable to assume that one of the main sources of technological progress will come from Artificial Intelligence. Many AI researchers believe that we will reach human-level AI in the next few decades , certainly within this century.

When that happens, the human-level AI will acquire all the knowledge we possess and will be able to produce increasingly more intelligent AI, reaching super-intelligence level very rapidly or producing what some have called an intelligence explosion or the Singularity.

I have written about this on Automation: the Endgame , so I won’t repeat myself here, but a super-intelligent AI at our service, if we can control it (a big if), would usher a new era of scientific discoveries and technological advances, that would create a world unimaginable for us today. On the flip side, if not managed well, an entity much more intelligent than us could also mean our end as a species.

Apart from advances in AI, we will undoubtedly see advances in genetics and DNA sequencing and engineering. Ethics will have to play an important role here.

For example, will we want to create “designer babies” with no hereditary sickness? If so, why stop there? Why not make them beautiful, tall, strong, and more intelligent? Will we create an even more unequal society in which the super-rich create a super-human species and leave the rest of us in the dust?

These are questions that we will have to answer eventually, and the sooner, the better.

Without falling into full techno-utopianism, I believe technology has the potential to become a huge enabler, help us solve many of our current problems, and increase our living standards by 2100.

We will fight climate change by changing our behaviours, but without technological advances that allow us to store or eliminate the carbon dioxide in the atmosphere, it will be an uphill battle. Same with producing food for 11 billion people, fighting the next pandemic, or helping us solve any of the big global problems we will be facing in the next few decades.

Technology brings its own risks, but without its help, we won’t be able to tackle the big challenges of our century.

Work in 2100, or lack thereof

On this site, we like to talk about the Future of Work . What will work be like in 2100? If work still exists, it is possible it won’t.

Suppose Artificial General Intelligence (AGI), human-level AI, or artificial super-intelligence are reached by the end of the century, as stated above. In that case, it is likely work will not exist. AI and robots will be able to do whatever we are capable of doing but faster and better .

As Stuart Russell explains in Human Compatible :

“General-purpose AI would be everything as a service (EaaS) . There would be no need to employ armies of specialists in different disciplines, organized into hierarchies of contractors and subcontractors, in order to carry out a project. All embodiments of general-purpose AI would have access to all the knowledge and skills of the human race, and more besides. (…) In principle -politics and economics aside- everyone could have at their disposal an entire organization composed of software agents and physical robots, capable of designing and building bridges, improving crop yields, cooking dinner for a hundred guests, running elections, or doing whatever else needs doing. It’s the generality of general-purpose intelligence that makes this possible.”

If this becomes true, it will be a time of abundance .

We will not need to work anymore, and we will have all our basic needs covered, but as has been the case throughout all of history, some people will have access to more abundance than others. This will probably be an extremely unequal society unless we do something to remedy it now.

However, it is not certain that this world will become true.

Like the already mentioned Kai-Fu Lee, some authors believe we are far from this scenario and that there will still be jobs for humans. The number of jobs that machines will do better than us will increase considerably, but there will still be jobs requiring a human touch and emotion.

What humans crave most is what machines will not be able to provide: love and human connection .

Whether jobs exist or have disappeared altogether, what seems clear is that we will probably have much more free time in 2100. In a society like ours, where careers and jobs play such an essential role in providing us with meaning, social status, and economic worth, there will have to be a total change of mindset, even a new paradigm. We will have to find a new meaning in life in a world without work .

Like Ancient Greeks or wealthy nobles throughout history, we will have to find ways to enjoy all our available leisure time.

Looking at the latest trends, we will probably spend most of our free time staring at a screen or immersed in a virtual world, playing games and having virtual sex. Still, people will also spend more time learning new skills, following artistic pursuits, and unleashing their creative instincts.

We may see a new flourishing of the arts and creativity , a modern Renaissance perhaps.

A more human and humane future

There are many other possibilities we haven’t explored in this article.

Will there be a human colony on Mars by 2100? Possibly.

Will we have found a Theory of Everything in physics? Who knows.

Will we know for sure whether there is life after death? Unlikely.

I find it exciting to think about and reflect on the future. As I said initially, I don’t make predictions, but I like to think about possibilities and possible futures and then work towards the most desired one.

The future doesn’t happen to us; we build and shape it. We have agency over it, but we need to start building it today .

Depending on the actions we take now, the world will be slightly or intolerably warmer at the end of this century, or the world population will go up to 9 or maybe 11 billion people. Depending on the politicians we vote for and other actions we take, we will have one type of world order based on collaboration and cooperation or a completely different one based on confrontation and war.

Finally, depending on our decisions as leaders , employees, founders, shareholders, consumers, and clients, we will build more or less human and humane workplaces and societies.

We can use the exponentially growing advances in technology to maximise our potential as a species, increase our living standards, and live more fulfilling lives, or alienate ourselves, exploit one another, and increase human suffering.

Which one will it be?

I hope we choose wisely.

For a more human and humane future ! May you all get to 2100 in good health and happiness!

For fictional scenarios of the future, read the Possible Futures series:

Possible Futures – A day in your life in 2040

A dystopian world – the collapse of society

Possible Futures – Life in the Age of Abundance

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Iker Urrutia

[…] Articles What will the world be like in 2100? Why a Humane Future of Work? Future of Work: all you need to […]

Hi Iker! I wanted to know what will happen in the future and it sounded so interesting so I wanted to say that I like it. I like your article by the way. Thanks!

This was cool

Hi. i came here and I’m pretty sure I’m going to die in 2100 so i wanted to know what it is going to be like. Thanksi

So, should you live to be 121 and you’re disappointed in where we are at, you will simply say ‘it’s Trump’s fault’?

Hi Dan, thanks for leaving a comment. In this post, I mentioned climate change, demography, geopolitics, exponential technologies, and how this might affect the future of work. Throughout the entire post, I made it quite clear that we have agency to build our future, it doesn’t just happen to us. We will build this future together, so we’ll succeed or fail together. I am not sure where you got the idea that I would blame Trump for the state of the world in 2100? You assign him too much power if you think he’ll have much impact on the state of the world almost 80 years from now, or even to think I’ll still remember him if I get to live to the tender age of 121.

Hello sir !!!

I am from Sri Lanka. I am 7 years old.

I recently wanted to find out what the future holds. There was a lesson in my English book called The Future. Then I came across this website. The contents of this book are very similar to the ones in my English book. However, I was able to find a lot more information.

Thank You Sir !!!

You will most likely be alive and well in 2100 to experience it yourself! I wish you a happy life.

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What will America’s population look like by 2100?

The Census Bureau estimates there will be 1.2 million more deaths than births in the year 2100.

Published Fri, January 26, 2024 by the USAFacts Team

By 2100, the United States will be home to 366 million people, according to Census Bureau projections . That’s 32 million more people than in 2022, but it also indicates a slight decline from a projected peak down the road.

The Census Bureau projects America’s population to grow older and more diverse by the end of the 21st century, with immigration and fertility rates driving most changes through 2100.

The Census also projects immigration will be the largest driver of population growth through the rest of the century. Without any new immigration, the Bureau estimates the nation’s population would begin declining in 2024, resulting in approximately 107 million fewer people in 2100 than in 2022. Conversely, it also projects a high-immigration scenario in which the US could have an estimated 102 million additional people by then.

How much is the US population predicted to grow by 2100?

The Census projects the population will grow by 9.7%, or 33 million people, between 2022 and 2100. That’s roughly equivalent to the current population of Texas . According to these projections, the US population will peak at 369 million people in 2080 before declining through the rest of the century.

What are the predicted birth and death rates for the US?

US birth rates are predicted to decline throughout the remainder of the 21st century, from 10.8 births per 1,000 people in 2023 to 8.5 per 1,000 in 2100. Meanwhile, the death rate will increase from 8.5 per 1,000 people in 2023 to 11.9 per 1,000 in 2100.

Fertility rates have generally declined in the US since the late 1950s, and the share of the population over 65 has increased . The Census expects these trends to continue, resulting in a death rate that exceeds the birth rate by 2038. By 2100, the Census Bureau estimates there will be 1.2 million more deaths in the US than births.

Line graph showing census projections for US birth and death rates, 2023–2100. Deaths are expected to exceed births in the US by 2038.

How is immigration expected to change the total US population?

The Bureau expects immigration to drive population growth through the remainder of the 21st century. In every projected year, the number of people moving into the US is expected to exceed the population change that would result from births and deaths alone.

How could US demographics shift?

The US population is projected to get older and more diverse through the rest of the 21st century. Within a decade, seniors will outnumber children, and by 2050, the non-Hispanic white population will be less than half of the US population.

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What is the predicted median age of the US population?

The median age in the US is expected to increase to 47.9 years in 2100, up from 38.9 years in 2022. As the population ages, the Census expects there to be more seniors than children in the US in 2100. By that time, 29.1% of all people in the US will be 65 and over, compared with 16.4% under 18. In 2022, 17.3% of the population was 65 or over, and 21.7% were under 18. The two groups are expected to each constitute 20% of the population in 2030.

Line graph comparing projected share of US population under 18 or 65 years and older, 2022–2100. Nearly three in 10 Americans will be 65 or older in 2100.

How will the ethnic makeup of the US change?

The Census Bureau provides race and ethnicity projections through 2060. By that point, the non-Hispanic white, Hispanic, and non-Hispanic Black populations will remain the three largest race or ethnic groups nationally. The non-Hispanic white population will make up less than half of all people in the US, while the Hispanic or Latino [1] population will grow to more than a quarter.

The non-Hispanic white population is projected to decrease from 58.9% in 2022 to 44.9% in 2060. The Hispanic or Latino portion of the population will increase the most of any group, from 19.1% in 2022 to 26.9% in 2060. The non-Hispanic Black population is expected to remain around 13%, growing from 12.6% in 2022 to 13.4% by the end of the century.

Area chart showing the projected population distribution by race and ethnicity in the US from 2022 to 2060, with the white category shrinking over time.

Where does this data come from?

The Bureau makes population projections based on birth, death, and international migration patterns. The data in this article is from the 2023 National Population Projections “main series” (also known as the “middle series”), which the Census Bureau considers the most likely outcome of the scenarios it has projected.

Find out more about our aging population and get the data directly to your inbox by signing up for our newsletter.

The federal government defines "Hispanic or Latino" as a person of Cuban, Mexican, Puerto Rican, South or Central American, or other Spanish culture or origin regardless of race.

Explore more of USAFacts

Native Americans and the US Census: How the count has changed

How are age-related demographics changing in U.S. states?

How many daca recipients are there in the united states.

Immigration demographics: A look at the native and foreign-born populations

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An illustration of Earth approximately 3.7 billion years ago, when microbial life was beginning to form near hydrothermal vents as fierce lighting storms flash through the sky.

How did life on Earth begin? Here are 3 popular theories.

For millions of years, Earth was a hot and rocky planet. Scientists have some hypotheses on how life emerged amid such inhospitable terrain.

Earth formed roughly 4.6 billion years ago, and for several hundred million years the planet’s surface was almost certainly too hot and heavily bombarded by comets and asteroids to be hospitable to any kind of lifeform. About a billion years later, life not only existed, but was also leaving evidence of its presence in the form of fossilized microbial mats .

So, what happened in the interim? How did life spring from non-life over the course of a half billion years or so?

1. Sparked by lightning

Atmospheric conditions at the time life appeared were very different from those that exist now, notes Jim Cleaves, chair of the chemistry department at Howard University and co-author of A Brief History of Creation: Science and the Search for the Origin of Life.

In the 1950s, he explains, Nobel Prize-winning chemist Harold Urey noted that most atmospheres in the solar system are dominated by nitrogen and methane; Urey reasoned that early Earth also had this type of atmosphere, and that the presence of life transformed it into one richer in oxygen. Urey also proposed that this earlier atmosphere “could be very efficient at making organic compounds, which could be the precursor to life,” Cleaves explains.

He tasked his research student Stanley Miller with developing an experiment to test this theory. What would become known as the Miller-Urey experiment created a closed system, in which water was heated and combined with molecules of hydrogen, methane, and ammonia. These were then zapped with electricity (to represent lightning) and cooled to allow the mixture to condense and fall back into the water, like rain.

The results were astonishing.

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Within a week, the experimental “ocean” had turned reddish brown because of the molecules combining to create amino acids, the building blocks of life.

Subsequent research has shown that the planet’s early atmosphere was somewhat different from the experiment created by Miller, and that the main components were nitrogen and carbon dioxide, with hydrogen and methane present in smaller quantities.

The principles espoused by Miller remain broadly sound, however, with lightning combining with asteroid impacts and ultraviolet radiation from the Sun to create hydrogen cyanide , which then reacted with iron brought up by water from Earth’s crust to form chemicals such as sugars . These chemicals may have combined to create strands of ribonucleic acid, or RNA , a key component of life that stores information; at some point, RNA molecules began replicating themselves, and life was possible.

How did these RNA molecules develop into complex cellular structures surrounded by protective membranes?

The key may be coacervates—droplets that contain proteins and nucleic acids and which are able to bind their components together much as cells do, but without the use of membranes; several researchers have hypothesized that such droplets acted as protocells that concentrated early RNA and other organic compounds .

2. Brought to Earth by outer space

Amino acids, as well as some of the other key building blocks of life such as carbon and water, may have been brought to early Earth from outer space, according to another theory. Comets and meteorites have been found to contain some of the same organic building blocks of life, and their early bombardment of Earth may have increased the availability of amino acids .

Life probably exists beyond Earth. So how do we find it?

The 11 most astonishing scientific discoveries of 2023

Saturn’s ‘Death Star’ moon was hiding a secret: an underground ocean

According to Nobel Prize-winning chemist Jack Szostak of the University of Chicago, who heads the university’s interdisciplinary Origins of Life initiative, asteroid and comet impacts were almost certainly integral.

He notes that an early atmosphere of nitrogen and carbon dioxide would have been less conducive to some of the proposed chemical reactions that took place in Miller’s concoction of hydrogen, methane and ammonia; but, he explains, a moderate sized impact can create atmospheric hydrogen and methane on a transient basis , allowing for a temporary jolt of compound-creating conditions.

“It’s like having your cake and eating it,” he explains.

3. Hiding in Earth’s oceans

Another theory postulates that life may have begun deep in the ocean, around hydrothermal vents on the sea floor , but Szostak dismisses this hypothesis.

“If you look at the chemistry that takes you from simple starting materials up to nucleotides and RNA, there are multiple steps in there that require UV radiation from the sun to drive the reactions,” he explains. “Energy from the Sun is the is the is by far the biggest source of energy, even on the early planet. So, if there are multiple chemical steps that require UV, you can't be in the deep ocean.”

It is all but certain that life did begin in water, however.

“You need a solvent for the chemical reactions to take place,” Cleaves points out. “You need a liquid. And when you start talking about liquids, only a few are stable under planetary surface conditions. And, even in the early solar system, water happens to be the most abundant.”

Szostak argues that, far more likely than life starting in the deep ocean is that it became established “on the surface, probably in shallow ponds or in a hot springs type of environment: the kind of environment that's very common around impact sites or volcanic regions.” (Indeed, extensive volcanic activity also may very well have contributed to life becoming established, not least by generating enormous amounts of localized lightning .)

It is possible that, although all life on Earth today shares a universal common ancestor , an unknown microbial lifeform that has presumably long since disappeared, life itself may have started on multiple different occasions via several different pathways, only to be snuffed out by cometary impacts or simply fail to gain traction, until the RNA-based molecule that is the ancestor to us all became established.

“It may really have been a roll of a dice,” says Cleaves.

Early life remains mysterious

If that did happen—if life started and fizzled out more than once before it took root—we will almost certainly never know what might have been, as such putative lifeforms have left no trace of their existence.

Life could have followed a very different path, one that would not have led to flowers or trees or dinosaurs or humans. The key to comprehending all of it, says Szostak, is to replace the big picture question with a series of much smaller ones.

“Life is such a complicated system that the simplest bacteria or virus has thousands of moving parts. It's hard to understand how something like that could just appear out of nowhere,” he says. “And the answer is that it didn't. It happened step by step by step.”

Tonga's volcanic eruption triggered a staggering 2,600 lightning flashes a minute

4.5 billion years ago, another planet crashed into Earth. We may have found its leftovers.

In the hunt for alien life, this planet just became a top suspect

A 280-mile-long volcano may have been discovered on Mars—hiding in plain sight

What we know from decades of UFO government investigations

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COMMENTS

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The world in 2100 will be a totally different place. What we know today will be long gone, and all of the new technologies will take the place of the ones that are familiar to us. In the year 2100, it will be possible for people to connect to a worldwide network. The ideas of billions of people will be available for anyone to access.
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The origin of life on Earth stands as one of the great mysteries of science. To find out if we are alone in the galaxy, we will need to better understand what geochemical conditions nurtured the first life forms. Several seminal experiments in this topic have been conducted at the University of Chicago, including the Miller-Urey experiment that suggested how the building blocks of life could ...
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Source: Adapted from Fig. 3, B. C. O'Neill et al. Geosci. Model Dev. 9, 3461-3482 (2016) These scenarios update a set that has been in use for the past decade, including one extreme — and ...
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Climate Change: What Happens after 2100?
The carbon that we are releasing into the atmosphere today is in the process of 'programming' a potential 2-5 metres of sea level rise by around the year 2300. But that's not all. The report also states that "even a thousand years after reaching a zero-emission society, temperatures will remain elevated, likely cooling down by only a ...
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Hausfather, along with co-author Schmidt, compared 17 model projections of global average temperature developed between 1970 and 2007 with actual changes in global temperature observed through the ...
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The world in 2100 will be hotter, with more extreme weather and more natural disasters such as hurricanes and wildfires. How much hotter? It is impossible to know right now, as it will depend on our actions during the next 80 years. There are different scenarios, from the world being 1.5ºC to 5ºC hotter by 2100. There is a big difference ...
What will America's population look like by 2100?
The median age in the US is expected to increase to 47.9 years in 2100, up from 38.9 years in 2022. As the population ages, the Census expects there to be more seniors than children in the US in 2100. By that time, 29.1% of all people in the US will be 65 and over, compared with 16.4% under 18. In 2022, 17.3% of the population was 65 or over ...
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2. Brought to Earth by outer space. Amino acids, as well as some of the other key building blocks of life such as carbon and water, may have been brought to early Earth from outer space, according ...
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Create a hypothesis of what life will be like in 2100 with introduction, idea 1, idea 2, idea 3 (Cree una hipótesis de cómo será la vida en 2100 con introducción, idea 1, idea 2, idea 3) Escribe un párrafo de 90 palabras. me ayudan plis Ver respuesta Publicidad Publicidad