The Uninhabitable Earth, a summary

Alberto Savinio, Oggetti Nella Foresta, 1927

I think climate change will hit harder elsewhere, not here. I’m confused by the smallness (two degrees), the largeness (trillion tons of carbon), the abstractness of the numbers. I don’t know what to think or make of every new, alarming fact about this hybrid monster I can’t see or smell. Given our brains’ limited processing power, I can’t even think about it concretely. Climate change covers the entire surface of Earth and its effects extend up to more than 500 years into the future. Do you remember what life was like in 1510? This spookiness of scale discomforts me. Ecosopher Timothy Morton calls climate change a hyperobject, time-and-space-stretched to such an extent that it becomes almost impossible to hold in mind. Connected with all lifeforms, many of them dying out, in a complex way. How do you mourn for everything that will get lost, is getting lost, already has been lost? Reefs, species, oceans, crops, forests. That’s a lot of goodbyes. I try to act in small ways, avoiding cars and planes as much as possible, buy renewable energy, eat near to no meat. Otherwise I tend to save all the doom for later, quietly going about my life.

And then, after a few days of ignoring, you read the words “It is, I promise, worse than you think”. This is how David Wallace-Wells begins his article “The Uninhabitable Earth” on July 9 in New York Magazine. He gives you a worst-case-scenario tour of climate change scenarios, in a way you haven’t seen before. The response since has been extraordinary, both in volume (most-read article in the magazine’s history) and in kind. Climate scientists criticized the article for being overstated, a paralyzing narrative of doom, producing extraordinary claims without extraordinary evidence.

Fossils by Heartless Machine, from The Uninhabitable Earth — New York Magazine

One week later, Wallace-Wells reacted and published an annotated version showing the facts, research, and science behind his claims. It’s baffling. But the debate about the article is maybe less about facts than about effects. Is it helpful, or ethical, to explore the worst-case scenarios of climate change, however unlikely they are? How much should a writer contextualize scary possibilities with information about how probable they are? What are the risks of terrifying or depressing readers so much they disengage from the issue? I agree with Wallace-Wells that we should — at least — be aware of the scenarios, that many more people are not scared enough than too scared, that the public complacency is a far bigger problem than widespread fatalism, all of which gives the majority of politicians excuses to be deadly conservative, ignoring threats posed by climate change, and thus turning a blind eye to their own children and grandchildren. Most politicians will only act when there is a broad-based support.

Not the information itself, but how you react to it is key. Neither partying, nor preparing, nor praying, nor postponing doom into some hypothetical future, achieves what should be the goal when we perceive a threat on the horizon: we should not seek to ignore it, or simply brace for it, but to avert it. The hyperobject is real and has already intruded the ecological, social and psychic space.

When it comes to warming dangers, we suffer from an incredible failure of imagination. The reasons for that are many : the timid language of scientists, climate denialism which has made scientists even more cautious in offering speculative warnings, a culture that doesn’t see warming as a problem worth addressing, the domination by a group of technocrats who believe any problem can be solved, the fact that we only can see effects now of warming from decades past, our uncertainty about uncertainty, the way we assume climate change will hit hardest elsewhere, the numbers, the discomfort of a very difficult problem, the incomprehensible scale, and simple fear.

Below, I summarized the article to a certain extent - including the annotation-nuances - for readers who only have time to skim it. What Wallace-Wells writes is too important to ignore. Following the current trends, it’s highly probable that your children, and you, will experience some of the terrors this article describes. We should be alarmed.

TRINITY TEST at 0,016 seconds, July 16, 1945. The first detonation of a nuclear weapon. Conducted by the United States Army at 5:29 am, as part of the Manhattan Project, in the New Mexico desert. For some time this picture was banned, since it was considered far more provocative than the habitual mushroom cloud. The tiny black dots at the bottom are trees.


The “Uninhabitable Earth” wants to understand where the planet is heading without people taking major actions. Its central aim is to apply the best science to the IPCC’s “business-as-usual” warming projections, which assume future trends and policies will follow those of the past. The findings are the result of dozens of interviews and exchanges with climatologists and researchers in related fields and reflect hundreds of scientific papers about climate change.

4 ° Celcius by 2100

  • What is the IPCC’s “business-as-usual” warming projection? If we stay the present course, we will hit 4 degrees (medium projection) to 8 degrees (upper end) of warming by 2100. Although IPCC projections are considered the “gold standard”, they are said to underestimate what is to come. So it might be more. Also, they don’t take into account the permafrost melt, only partly take into account the albedo effect (less ice, more absorbed light, more warming), more cloud cover (trapping heat), reduction of forests (less carbon storage). More about the effects of 4 degrees by 2100, below.
  • How likely is this “business-as-usual” outcome? Difficult to say. To make a projection, many variable inputs are needed on top of the already complicated natural system that delivers both amplifying and moderating feedbacks to greenhouse-gas effects. An attempt. Our chances of staying below the Paris goal of 2 degrees warming by 2100 is 10 percent (Princeton). The mean is about 3.5 degrees of warming, and there is 15 percent probability to overshoot 4 degrees (Columbia) or even 6 degrees.
  • Remarkable and recurring in the article is that past predictions systematically prove to be conservative. The Arctic began losing sea ice several decades ahead of every IPCC climate model, for example, which means the Arctic region warmed up faster than scientists expected. Something to consider.
  • The history of the planet shows that the temperature can shift 5 degrees Celsius within 13 years. The last time the planet was 4 degrees warmer, the oceans were 30 m higher. The most notorious mass exctinction began when carbon warmed the planet by 5 degrees, ending with 97 percent of all life dead. We are currently adding carbon at a ten times faster rate.
  • Today, we’ve warmed the world 1 degree. The general impression is that each degree is more damaging than the previous one. Most estimates are that the first degree was almost free, but we can see a dotted line into Syria. The second degree will cost more than the first degree, and so on.
  • It’s important to remember that climate effects are not binary. There are no “two options” — lethal heat waves and normal temperature, no harvests and normal harvests, no conflicts and worldwide wars. Global warming will gradually bring about more and more problems.

Permafrost Wild Card

  • Until recently, permafrost was not a major concern. Now it is, because it’s melting at accelerating rates. The permafrost contains twice as much carbon as is currently suspended in the atmosphere. Some of the carbon will be — gradually — released in the form of methane, a 86 times stronger greenhouse gas. Also, the thawing permafrost will turn the Arctic from a sink that stores carbon to a source that generates carbon in the 2020s. Probability? According to the IPCC, it is virtually certain that near-surface permafrost will be reduced by 37% to 81% by 2100. Half of the amount of carbon that has been released since the industrial age, may be additionally released. Today, none of the current IPCC predictions include carbon dioxide or methane emissions from warming tundra as a feedback. Also, none of the warming scenarios described in this article are built on the premise of a methane release from permafrost. The permafrost melt is a wild card which could add to the IPCC projections. It could even add a degree of warming by 2100 all on its own.
  • Anekdote-parable. Norway’s seed bank, designed to ensure that our agriculture survives any catastrophe, has been flooded by meltwater last winter because of the unusually warm temperatures at the North Pole. The “Doomsday vault” is fine for now, the flooding was not catastrophic, but apparently no engineer expected this to happen 10 years ago, when the vault was built.

What Will Get Lost

  • We’ll loose Miami and Bangladesh within the century, even if we stop burning fossil fuel in the next decade. Bangladesh is doomed. Not so much because of the massive floods, but because of the salt infilatration wich will destroy the crops. This will already happen at 1.5 degrees of warming. Two degrees of warming is used to be considered the threshold of catastrophe, but at that treshold already tens of millions of climate refugees will be unleashed upon an unprepared world. This is ignored to date.
  • Four degrees of warming would eliminate between 40 and 70 percent of the world’s species. Mass extinctions are especially interesting in terms of what happens after them, they reset the planetary clock. The recovery fauna is totally different. In the past, all extinctions but one were caused by greenhouse gases. It’s going completely in the wrong direction, with no sign that the planet as a whole has the problem under control. This is why Stephen Hawking and Elon Musk say we need to colonize other planets in the next century to survive.

Heat Stress, Heat Death

  • Sea-level rise, and the cities it will drown, is barely scratching the surface of what terrors are possible. Fleeing the coastline will not be enough. Other threats are closer at hand. Parts of the Earth will become almost uninhabitable or inhospitable, by the end of this century.
  • At 4 to 6 degrees warming, people will start evacuating the tropics (where humidity adds to the problem), not being able to work outside, because of heat stress, crop failure, etc. At present, most regions reach a wet-bulb maximum of 27° C; the red line for habitability in the tropics is 35 degrees. Heat stress comes much sooner. In the jungles of Costa Rica, simply moving around outside when it’s over 40° C would be lethal. Our bodies would switch from giving off heat to the environment, to gaining heat from it. Climate-change skeptics point out that the planet has warmed and cooled many times before, but the climate window that has allowed for human life is very narrow.
  • At 6 degrees warming, heat stress in New York City would exceed that of present-day Bahrain, one of the planet’s hottest spots, and the temperature in Bahrain would induce hyperthermia in even sleeping humans. Even if we meet the Paris goals of 2 degrees, cities like Karachi and Kolkata will become close to uninhabitable.
  • We’re about there already. Since 1980, the planet has experienced a 50-fold increase in the number of places experiencing dangerous or extreme heat. The five warmest European summers since 1500 have all occurred since 2002. Soon, the IPCC warns, simply being outdoors that time of year will be unhealthy for much of the globe. These effects will come about gradually, unusually hot days will gradually become more frequent in number.
  • The crisis will be most dramatic across the Middle East and Persian Gulf, where in 2015 the heat index registered 72°C in Iran. Several decades from now, the hajj will become physically impossible for the 2 million Muslims who make the pilgrimage each year. Air-conditioning can help (only richer countries) but will ultimately only add to the carbon problem.

The End of Food

  • The basic rule for staple cereal crops is that for every degree of warming, yields decline by 10 to 17 percent.
  • Theoretically, a warmer climate will make it easier to grow corn in Greenland, but the tropics are already too hot today to efficiently grow grain, and the places where grain is produced today are already at optimal growing temperature, which means even small warming will lower productivity.
  • If the planet is 5 degrees warmer at the end of the century, we may have 50 percent more people to feed and 50 percent less grain to give them.
  • Not eating meat would help. But today, many countries are shifting to more meat consumption per person. The demand for grains will go through the roof. Also, cows both burp and fart methane, a strong greenhouse gas.
  • Drought might be an even bigger problem than heat, with some of the world’s most arable land turning quickly to desert. By 2050, 5 billion people will live in water-stressed areas. By 2080, without dramatic reductions in emissions, southern Europe will be in permanent extreme drought. The same will be true in the Middle East; densely populated parts of Australia, Africa, and South America; and the breadbasket regions of China. The droughts in the American plains and Southwest will be worse than any droughts in a thousand years, including those that wiped out the Anasazi civilization in 1100–1300. There will be severe droughts nearly everywhere food is today produced. None of these places, which today supply much of the world’s food, will be reliable food sources.
  • Remember, we do not live in a world without hunger as it is. Far from it. Globally, there are 800 million undernourished today. Starvation in Somalia, South Sudan, Nigeria, and Yemen could kill 20 million this year alone.

Climate Plagues

  • Ice is frozen history, some of which can be reanimated when unfrozen. There are now, trapped in Arctic ice, diseases that have not circulated in the air for millions of years — in some cases since before humans were around. Our immune systems have no idea how to fight back prehistoric plagues. Smallpox, the bubonic plague and flu remnants are trapped in ice too.
  • Last year, a boy was killed and 20 others infected by anthrax released when retreating permafrost exposed the frozen carcass of a reindeer killed by the bacteria 75 years earlier; 2,000 present-day reindeer were infected, too, spreading the disease beyond the tundra.
  • What concerns epidemiologists more than ancient diseases, is the relocation or re-evolution of existing diseases. Global warming will shake up our ecosystems and help disease trespass geographical limits. As the tropics creep northward and mosquitoes migrate with them, Europeans will worry about dengue, malaria or Zika. Also, for every degree increase in temperature, the parasite of Malaria reproduces ten times faster. By 2050, 5.2 billion people will live in conditions where they could potentially be infected.

Unbreathable Air

  • Small increases in pollution can shorten life spans by ten years. By 2050, Americans will suffer a 70 percent increase in ozone smog, which raises children’s risk of autism tenfold, among others. The concentration of carbon dioxide by 2100 will be such that human cognitive ability will decline by 21 percent. By 2090, 2 billion people globally will be breathing air above the WHO safe level.
  • By 2050, wildfires will be twice as destructive as they are today. What worries people even more is the effect that would have on emissions, especially when the fires ravage forests arising out of peat, adding to the global CO2 release. There is also the terrifying possibility that rain forests like the Amazon could dry out enough to become vulnerable to forest fires — which would not only expel enormous amounts of carbon but also shrink the size of the forest. That is especially bad because the Amazon alone provides 20 percent of our oxygen.
  • Already today, more than 10,000 people die each day from the small particles emitted from fossil-fuel burning. Each year, 339,000 people die from wildfire smoke, in part because climate change has extended forest-fires.
  • Today, in Shanghai you can even taste air pollution. The Chinese “airpocalypse” of 2013 peaked at an Air Quality Index of over 800. Already in the 301-to-500 range, there is serious aggravation of heart or lung disease and premature mortality in persons with cardiopulmonary disease and the elderly, and serious risk of respiratory effects for all others. Smog was responsible for a third of all deaths in the country. In many cases, the smog worsened other medical conditions.

Perpetual War

  • Drought is behind a lot conflicts today. There is a strong positive relationship between warmer-than-average temperatures and increasing conflict. For every half-degree of warming, societies will see between a 10 and 20 percent increase in the likelihood of armed conflict. There’s a lot of evidence for example that the Syrian civil conflict was driven by the worst drought in 900 years, caused by climate change.
  • This doesn’t mean that every conflict has a climate root (Lebanon suffered the same crop failures as Syria), but on average climate works as a threat multiplier for conflict. A planet five degrees warmer would have at least half as many wars. Social conflict could more than double this century.
  • What accounts for the relationship between climate and conflict? Some of it comes down to agriculture and economics. Hot temperatures reduce agricultural productivity, which could alter farmers’ incentives to start a conflict. Joining a conflict is a way to try to put food on the table. A lot also has to do with forced migration, already at a record high, with 65 million displaced people wandering today. But there is also the simple fact of being more pissed off when it’s hot.
  • Civil wars often start with very small numbers of people. So you only need to affect the decisions of literally handfuls of individuals to get some of these conflicts.

Permanent Economic Collapse

  • In the aftermath of the 2008 crash, a growing number of historians studying “fossil capitalism” suggest that the entire history of economic growth is not the result of innovation, trade, or the dynamics of global capitalism, but simply the onetime injection of fossil fuels into a system previously characterized by global subsistence living. Of course, this injection of raw power has a devastating long-term cost.
  • Historically, the optimum temperature for producing things is about 13 degrees Celsius. Some of the largest economies in the world, coincidentally or not, are right at 13 degrees Celsius. Silicon Valley for example is now at the optimum temperature for producing things.
  • Every degree Celcius costs 1.2 percent of GDP, an enormous number. The median projection is for a 23 percent loss in per capita earning globally by the end of this century (resulting from changes in agriculture, crime, storms, energy, mortality, and labor). There is a 12 percent chance that climate change will reduce global output by more than 50 percent by 2100.
  • The scale of economic devastation is hard to comprehend, but try to imagine what the world would look like today with an economy half as big, producing only half as much value, generating only half as much to offer the workers of the world.
  • All this makes the idea of postponing government action on reducing emissions and relying solely on growth and technology to solve the problem an absurd business calculation. Every round-trip ticket on flights from New York to London, costs the Arctic three more square meters of ice. Which does suggest the wisdom of a carbon tax.
The Mirny mine is an inactive diamond mine in Siberia. One of the largest excavated holes in the world, 525 metres deep and with a diameter of 1,200 m.

Poisoned Oceans

  • The sea will become a killer, that’s a given. People expect 60 to 90 cm in the next hundred years. But there’s a bit of worry about the predictability. Without a radical reduction of emissions, we will see at least 1,2 meters of sea-level rise and possibly 3 meters by 2100.
  • A third of the world’s major cities are on the coast. When looking at extremely large cities — populations above 5 million — nearly two-thirds are on the coast, not to mention its power plants, ports, navy bases, farmlands, fisheries, river deltas, marshlands, and rice-paddy empires. Even those above ten feet will flood much more easily, and much more regularly.
  • The drowning of homelands is just the start. More than a third of the world’s carbon is sucked up by the oceans today (else, we’d have much more warming already). This results in ocean acidification, which will add a half degree to warming this century on its own, bleach corals, lower marine life, hamper fish populations, and reduce food supply for humans.
  • Ocean acidification can do much more. It breeds microbes that create low-oxygen zones. First in the deep ocean, gradually moving up to the surface. These dead zones will grow like cancers in the future, choking off marine life and wiping out fisheries. This is already quite advanced in parts of the Gulf of Mexico and Namibia, where hydrogen sulfide is bubbling out of the sea. Hydrogen sulfide is the planet’s preferred gas for a natural holocaust. It’s so toxic that evolution has trained us to recognize the tiniest traces of it. Long time ago, once all the feedback loops had been triggered, hydrogen sulfide killed off marine species that had dominated the oceans for hundreds of millions of years, and poisoned everything on land. Plants, too. It was millions of years before the oceans recovered. 97 percent of life on Earth died.

The Great Filter

  • So why can’t we see it?
  • The dramas of climate change are incompatible with the kinds of stories we tell about ourselves in novels, which emphasize the journey of an individual conscience rather than the poisonous miasma of social fate. Will it ever be normal to ask ‘Where were you at 400 ppm? Where were you when the Larsen B ice shelf broke up?
  • Movies and television, on the contrary, have been littered with apocalypse scenarios, not all climate-related but in some ways inflected by climate anxiety. Here, we didn’t fail to imagine climate change scenarios, but we have quarantined them, culturally, as something like parables, rather than stories that impress on us the real-world urgency of climate change.
  • Our blindness will not last — the changing climate will not permit it. In a six-degree-warmer world, the ecosystem will boil with natural disasters, out-of-control typhoons, floods and droughts, and other climate events that not so long ago destroyed whole civilizations. The strongest hurricanes will come more often, we’ll have to invent new categories to describe them; tornadoes will grow longer and wider and strike much more frequently, hail rocks will quadruple in size.
  • Humans used to watch the weather to prophesy the future, going forward. We will see in weather the vengeance of the past. Early naturalists often talked about “deep time” when they contemplated the profound geological slowness of nature. What lies in store for us is more like what the Victorian anthropologists identified as dreamtime: the semi-mythical experience of encountering in the present moment, an out-of-time past. You can find it already watching footage of an iceberg collapsing into the sea — a feeling of history happening all at once.
  • The story of the world’s kamikaze mission is the story of a single lifetime. Many people perceive climate change as a moral and economic debt, accumulated since the 18th-century Industrial Revolution. But 85% of the carbon we exhaled into the atmosphere has been emitted in just the past three decades, since World War II. In just a single generation, global warming has brought us to the brink of planetary catastrophe.
  • Some of the scientists who first identified climate change and raised the alarm, are still alive. Most of them believe that no amount of emissions reduction alone can help avoid disaster. Instead, they put their faith in various forms of geoengineering (carbon capture, sulfur dioxide approach). These — often untested — technologies are so far-fetched that many scientists regard them as nightmares because of the trillian dollar costs, high risks and ecological side-effects.
  • In the United States, Belgium, Netherlands and other countries, lawsuits take place against governments. They violate the “equal-protection clause” by failing to take action on warming, by imposing massive costs on future generations. These lawsuits are hugely significant (check the one in your area).
  • Several scientists propose global warming as the solution to Fermi’s paradox: If the universe is so big, why haven’t we encountered any other intelligent life in it? The natural life span of a civilization may be only several thousand years, and the life span of an industrial civilization perhaps only several hundred. In a universe that is many billions of years old, with star systems separated as much by time as by space, civilizations might emerge and develop and burn themselves up simply too fast to ever find one another.
  • This is the called the Great Filter. Civilizations rise, but there’s an environmental filter that causes them to die off again and disappear fairly quickly. If you look at planet Earth, the filtering we’ve had in the past has been in these mass extinctions. The mass extinction we are now living through has only just begun; so much more dying is coming.
  • Why do we have difficulty understanding truly existential risks? Human life has evolved in the absence of a species-extinguishing event, so historians have enormous overconfidence in our capacity to endure. We take the human experience as our only model of evolution, discounting entirely the infinite number of evolutionary branches cut dead elsewhere in the universe. As a consequence, we should have no confidence in historically based probability estimates for events that would extinguish humanity.
China’s second-largest dam, the Xiaolangdi on the Yellow River.
  • Scientists know that to even meet the Paris goals, by 2050, carbon emissions from energy and industry, which are still rising, will have to fall by half each decade; emissions from land use (deforestation, cow farts, etc.) will have to zero out; and we will need to have invented costly technologies to extract, annually, twice as much carbon from the atmosphere as the entire planet’s plants now do.
  • The planet is not used to being provoked like this, and climate systems that give feedback over centuries or millennia prevent us from fully imagining the damage done already to the planet. We have not developed much of a religion of meaning around climate change that might comfort us, or give us purpose, in the face of possible annihilation. Nevertheless, scientists have an enormous confidence in the ingenuity of humans — a confidence perhaps bolstered by their appreciation for climate change, which is, after all, a human invention, too. They have a strange kind of faith: We will find a way to forestall radical warming, they say, because we must. When we do truly see the world we’ve made, we will also find a way to make it livable. For them, the alternative is simply unimaginable.