1The Storm
The forecast is terrible. We face environmental, social and demographic catastrophe: drowned cities; stagnant seas; a crash in biodiversity; intolerable heatwaves; entire countries becoming uninhabitable; widespread hunger; and a global population of some 10 billion humans. A 3–4°C-hotter world is the stuff of nightmares and yet that’s where we’re headed within decades.
Our problems are systemic and they are feeding into each other to create a catastrophic avalanche for humanity. Polls show that most people around the world are now convinced that we are facing a ‘climate emergency’,1 but even this alarming phrase doesn’t encompass the sheer scale of disaster, which could be nothing short of global societal breakdown.
The amount of carbon dioxide in the atmosphere, which in 2022 reached 420 parts per million, is already higher than it’s been for at least the past 3 million years.2 It’s heating the planet beyond anything humans have experienced during our entire evolutionary history – and fast. As far as we know, only the instantaneous Cretaceous–Palaeogene meteorite impact event, 66 million years ago, caused more rapid global climate change than the current human-induced global heating. During that event, which famously killed off the dinosaurs, about 600–1,000 gigatonnes of carbon dioxide was released (with enormous amounts of other climate-changing gases).3 Now, we are the asteroid, taking just twenty years to release 600 gigatonnes of carbon dioxide.
We have created for ourselves a similarly perilous planetary situation, and we are barely better prepared than the dinosaurs for impending disaster. Collectively, the world has thus far failed to respond to the triple crises of poverty, climate change and ecosystem collapse at the scale and speed so desperately needed by the most vulnerable people.
Take climate change: we know that our carbon dioxide emissions are raising the temperature of the atmosphere and oceans, producing extreme weather events, a rise in sea levels, and altering rainfall patterns across the world. We know this is dangerous, and that we need to stop producing these emissions at a much faster rate – we need not just to match the rate at which carbon dioxide can be removed from the atmosphere, but cut below it. In other words, we need to go beyond ‘net zero’ emissions and start reducing down to safe levels the amount of carbon dioxide that’s already there. We know all this, but the vast, complex human economic, cultural and technological system – of which we are each a part – is slow to shift. We are continuing to chart a path towards a 4°C rise this century.4
The big reason for this heating is that global energy use is increasing (and will continue to do so for many decades), and most of this energy is generated by adding carbon dioxide to the atmosphere because it comes from burning fossil fuels. The obvious options then, determined by the physics of planetary heating, are: to produce much less energy; to capture the resultant carbon dioxide before it enters the atmosphere; or to produce energy without burning carbon. Once this physics equation is embedded into the real human world of socioeconomic and political systems, of course, things get more complicated. Anyone who argues that decarbonizing the world and fixing global warming is easy, is either a fool or a charlatan. This is the most complex problem that human society has faced. It’s hard. In addition, we have also made it harder for ourselves – by which, I mean, vested interests in the rich world have made it much harder than it might have been for the rest of the world, particularly for the poorest in the global south, who are also the most vulnerable to a hotter world. We created this problem because we are humans with all the capabilities, flaws and marvels that entails; we will solve it only as humans.
There are lots of encouraging signs that the world is starting to act. To begin with, there is now near-universal acceptance of the human-made global warming crisis. In 2015, the same year the world reached 1°C of global warming above pre-industrial temperatures, governments meeting in Paris pledged to keep the temperature rise to well below 2°C and ‘pursue efforts’ to limit the temperature increase to 1.5°C by 2100. The Glasgow climate meeting in 2021 began a ratcheting up of national emissions-reductions pledges, and we’ve also made some other key steps towards meeting the Paris Agreement, most impressively with the phenomenal rise in renewable electricity production. It is now cheaper to install a brand new solar or wind power plant than to continue producing electricity at an existing coal plant. In the UK, renewable power production has already regularly exceeded that from fossil fuels. The plunge in cost of renewables has coincided with an accelerated improvement in their capabilities. We have better, more efficient solar panels, wind turbines, batteries and electric vehicles, and are far more savvy about integrating electricity generated in this way into grid systems. All this will only improve.
However, exciting as this progress is, it represents a mere fraction of what is needed even to stabilize emissions, let alone reduce them. To keep below 1.5°C of heating, we’d have to halve global emissions by 2025, and reach net zero by 2050. Instead, our greenhouse gas emissions are still growing (the annual increase continued even despite the major industrial shutdowns caused by the Covid pandemic), temperatures are rising, ice-melt is accelerating, and climate change is, as scientists predicted, getting worse. Carbon dioxide levels today are more than 50 per cent higher than the pre-industrial average.
Many scientists think it highly unlikely that we will stay below a heating of 2°C by the end of the century, let alone the ‘safe’ target of 1.5°C. Most countries are not making anywhere near enough progress to meet their pledged emissions reductions – and even if they fulfilled them to the letter, the national targets are so inadequate that it would be far short of what’s needed to keep us below 2°C. Many countries significantly under-report their greenhouse gas emissions, so their climate pledges are anyway based on flawed data. China and India, the world’s first and fourth biggest emitters, will have higher emissions in 2030 than 2020. In 2021, the Finnish town of Salla, located inside the Arctic Circle, launched its bid to host the 2032 Summer Olympics. The first ice-free summer for the Arctic Ocean is expected in 2035.
Climate models predict that we’re on track for a heating of somewhere between 3°C and 4°C for 2100 – and bear in mind that these are global average temperatures. Subtract the seas from those calculations, and what you find is that, at the poles and over the lands where people live, the increase may be double that, meaning people could be experiencing an increase of as much as 10°C by 2100. If that seems a long time away, consider how many people you know will be around then. My children will be in their eighties, for instance, perhaps with middle-aged children and grandchildren of their own. We are making their world. It will be very different.
Let’s consider an entirely feasible planetary heating figure of 4°C by the end of the century, which is more likely than most people realize, so bear with me while I explain why. Climate modellers predict temperature rises based on various future emissions scenarios. The Intergovernmental Panel on Climate Change (IPCC) mapped out four different economic pathways (their term is ‘Representative Concentration Pathway’ or RCP) that we might take globally over the century: the ‘RCP 8.5’, in which we carry on business as usual with little attempt to decarbonize our economies; the moderate ‘RCP 6.0’, which sees emissions peaking by 2060 and then rapidly dropping; the intermediate ‘RCP 4.5’, which is more ambitious and sees emissions peaking by 2040 and dropping; and the very stringent ‘RCP 2.6’ pathway. Given current policies implemented since the COP26 climate conference in 2021, we are charting a pathway somewhere between RCP 4.5 and RCP 6.0, with the former now slightly more likely. Projections show that 4°C by 2100 is somewhere between definitely possible and reasonably likely.5 Indeed, we may well reach 4°C earlier than 2100, perhaps by 2075, even while sticking to the moderate pathway.
I’m using the UK Met Office plotted projections of change in global mean annual surface temperature (compared to pre-industrial temperatures) for the different emissions scenarios, since these factor in real-world systems, where things get messier. For instance, as soil heats up, biomatter decays faster, releasing more carbon dioxide into the atmosphere faster. The plumes represent the best estimate of the combined uncertainties in the modelling system, including things like cloud and water vapour feedbacks, which aren’t included in the main IPCC projections. The plumes might get smaller as new understanding is brought in to the models – but on the other hand, there are still things that are not fully included in a detailed way, like the effects of permafrost thaw and fires.
The rise in global temperature by a few degrees each decade will barely register for many people; the urgent problem is the extreme events the extra heat will trigger – heatwaves, flash floods, violent hurricanes and devastating fires. These are what overturn people’s lives.
Alarmingly, there are signs that we may be tracking above the moderate pathway. Research published in 2021 found the melting of ice across the planet is accelerating at a record rate, with the rate of loss now in line with the worst-case scenarios of the IPCC.6 About half of all the ice lost was from land, which contributes directly to global sea-level rises, with melting of the Greenland and Antarctic ice sheets speeding up the fastest, putting us on track for a sea-level rise of 1 metre by the end of the century. At the end of 2021, researchers reported huge and growing cracks in the Thwaites Glacier, a mass of ice the size of Britain or Florida that stretches across western Antarctica.7 The floating shelf of the glacier could snap off into the ocean in as little as five years, they warned, triggering a chain reaction of collapse. A complete loss of the Thwaites could raise ocean levels by an additional 65 centimetres – or by several metres, if the collapse brings down surrounding glaciers with it. At least 28 trillion tonnes of land ice have been lost in the past twenty-five years – enough to put an ice sheet 100 metres thick across the UK, researchers calculated. And a loss of bright ice often exposes darker rock or ocean, speeding up further heating as the sun’s heat is absorbed rather than reflected. In 2021, Arctic researchers announced that a significant part of the Greenland ice sheet is also on the brink of a tipping point, after which accelerated melting would become inevitable even if global heating was halted.8 All things considered, a global temperature rise of 4°C by 2100 seems likely enough to plan for.
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An average heating of the entire globe by 4°C would render the planet unrecognizable from anything that humans have ever experienced.
The world has reached a 4°C-hotter temperature before – well before humans appeared – some 15 million years ago, during the Miocene Era, when intense volcanic eruptions in western North America emitted vast quantities of carbon dioxide. Sea levels rose some 40 metres higher than today: the Amazon River ran backwards, California’s Central Valley was open ocean, a seaway stretched from western Europe to Kazakhstan, spilling into the Indian Ocean, and lush forests grew in Antarctica and the Arctic. Atmospheric carbon dioxide rose up to about 500 parts per million, a level that today represents something close to the most ambitious and optimistic scenario possible for limiting our future carbon emissions. However, that global heating took place over many thousands of years, giving animals and plants time to adapt to new conditions and, crucially, the world’s ecosystems had not been degraded by humans.
Things look bleak for our 2100 world, with plenty of extinctions as species struggle to migrate and adapt. In the oceans, we’re looking at vast dead zones as pollutants combine with warmer waters to produce an explosion in algae that starve marine life of oxygen. On top of this, ocean acidity from dissolved carbon dioxide will cause a mass die-off of shellfish, plankton and coral – reefs will be lost well before 2100, at somewhere between 2°C and 4°C. Without coral reefs, which act as fish nurseries, fish populations will also plummet globally.
Sea levels will be perhaps two metres higher by 2100. We will by then be well on our way to an ice-free world, having passed the tipping points for the Greenland and west Antarctic ice sheets,9 committing us to at least 10 metres of sea-level rise in the centuries beyond. By 2100, we will also have lost most other glaciers, including those that feed many of Asia’s important rivers.
A wide equatorial belt of high humidity will cause intolerable heat stress across most of tropical Asia, Africa, Australia and the Americas, rendering vast areas uninhabitable for much of the year. Tropical forests of heat-tolerant species may well thrive in this wet zone, with the high carbon dioxide concentrations, especially with the disappearance of human infrastructure and agriculture, although the conditions will probably favour vine-like lianas over slower-growing trees.10 To the south and north of this humid zone, bands of expanding desert will also rule out agriculture and human habitation. Some models predict that desert conditions will stretch from the Sahara right up through south and central Europe, drying out rivers such as the Danube and the Rhine.
In South America, models predict a weakening of the easterly trade winds over the Atlantic, drying the Amazon, increasing fires and turning the rainforest into grassland. The tipping point for the Amazon could well be triggered by deforestation; while the intact forest could cope with some drought because it generates and maintains its own moist ecosystem, areas that have been opened up through degradation allow moisture to escape, pushing it to a savannah state. By 2050, tropical rainforests, including the Amazon, may well be pumping out more carbon dioxide than they absorb.
This will undoubtedly be a more hostile, dangerous world. Heat will make large areas of the globe uninhabitable, and we will struggle to feed ourselves. Many of the places where people grow food will no longer be suitable because of heat stress or drought; despite stronger precipitation, the hotter soils will lead to faster evaporation and most populations will struggle to secure enough fresh water. Global food prices will soar, forcing tens of millions of hungry people onto the streets, into cities and across borders. Higher sea levels will make today’s low-lying islands and many coastal regions, where nearly half the global population live, uninhabitable, thus generating an estimated 2 billion refugees by 2100, according to some forecasts.11
A 4°C world is a terrible prospect, uninhabitable for billions of people. I fervently hope we won’t get there, but look where we are now at just 1.2°C above pre-industrial temperatures. Globally, it’s already hotter than it’s been in more than 100,000 years.12 The only reason we don’t already see a vastly different world, with forests flourishing in Antarctica, is that such changes take time. The world’s systems are responding but aren’t yet in equilibrium with the very recent changes to the atmosphere – that will take centuries.
We are leaving the sanctuary of an unusually stable climatic era in Earth’s history – one which enabled crops to be grown and the flourishing of human civilizations.13 We can already see its beginnings as we are thrown from one extreme weather disaster to another. Alarmingly, the global water cycle – the pattern of how water evaporates and is precipitated back down around the world – is now speeding up at twice the rate predicted by climate models and is likely to intensify by up to 24 per cent by the end of the century.14 This would bring more intense and frequent hurricanes, dumping significantly greater volumes of rain. And it could well lead to a shift in key weather systems, such as the Intertropical Convergence Zone (ITCZ), a band of precipitation that hovers around the equator, where the trade winds meet in the tropics. The ITCZ feeds monsoons, and throughout history its position on the planet has meant life or, as befell the Classic Mayan civilization, perhaps death. Climate models disagree on how the ITCZ will react in our heating world, but we are heading towards a world of increasingly frequent and intense droughts and their opposite: deadly storms and floods.
Even reaching 1.5°C, expected by the early 2030s, is no picnic. At this temperature, around 15 per cent of the population would be exposed to deadly heatwaves at least every five years – that’s 1.3 billion people, rising to 3.3 billion people at 2°C. By 2°C, bad harvests are twice as likely, and fish catches will have declined by twice as much as today. Sea levels are already rising faster than even the most pessimistic predictions.15
Our future world is one depleted of the biodiversity we’re dependent on, and where we’re facing a cocktail of negative shocks all the time, from fires to droughts. Within decades, we risk a turbulent, conflict-ridden world with great loss of life and perhaps the end of our civilizations.
Copyright © 2022 by Gaia Vince