What Is The “Hothouse Earth” Theory And How Can It Be Avoided?

A new study warns that we're approaching a series of tipping points that will lead to a Hothouse Earth, but we can still prevent this disaster.

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With soaring temperatures and roiling heat waves across the Northern Hemisphere this summer, it’s no surprise that the media was fascinated by a new study showing how we could be entering a long-term period called Hothouse Earth thanks to global warming. As we keep pumping greenhouse gasses into the atmosphere, average temperatures keep creeping upwards, and as they exceed 2 °C above normal, a number of very unpleasant things will happen, things we can’t undo. As a result, areas where millions of people live today will become uninhabitable due to heat waves, fire hazards, and persistent droughts, and rising sea levels will start flooding coastal cities, with major effects on agriculture, trade, and the global economy.

Basically, the study points out that when we emit greenhouse gases, there are certain natural carbon sinks which will absorb at least some of these gasses. Forests are one such sink. So are oceans and glacial ice. Certain types of rock can sequester some carbon as well. But as we keep polluting, the capacity of these sinks is exceeded, and they can no longer help protect us from ourselves. Likewise, because all these carbon reservoirs are all on the same planet and part of the same natural cycles, they affect each other, setting up a whole series of climate tipping points one after another, like dominoes. If we do nothing about it, we’ll be stuck on an uncomfortably hot world with all the logistical and geopolitical tensions climate change is already bringing us rapidly accelerated.

When we hit an average of 2 °C above normal, the polar ice caps will start melting away for good and oceans will start releasing ancient stores of greenhouse gases called hydrates. At 3 °C above normal, rainforests will begin to die off thanks to droughts, and desertification will speed up while ocean levels rise. Over 5 °C above normal will thaw permafrost and tundras will become a relic of the past. Each step will either contribute even more greenhouse gasses to the atmosphere, remove another carbon sink, accelerating the rate of change, or have serious long-term consequences for our cities, food sources, and health. And even if the Paris Agreement was fully implemented, we’d trigger all those tipping points by the early 2100s, especially after hitting that two-degree mark. But it doesn’t have to be this way.

We could try to adapt to toxic seafood and lower crop yields, try to fight diseases unleashed by melting permafrost, and spend the trillions of dollars to treat health problems caused by rampant pollution which is, unfortunately, making a huge comeback under the Trump administration. We can also brainstorm ways to deal with right-wing xenophobes and populists across the world who will mobilize against the rising tide of climate refugees. But why? Because it’s easier than developing a vision for the future and letting green energy companies create more jobs while cutting off the billions used to prop us fossil fuels and deal with the damage polluters are allowed to cause?

Thanks to small-minded inertia, we are effectively throwing money away not to change our ways and make a profit from doing something positive, then paying to clean up the side-effects. We’re going to have to live with some warming no matter what, but unless we go virtually all green and renewable by 2050, we’d be looking at a global humanitarian crises caused by droughts, famines, spreading disease, and wars for dwindling resources, as well as massive cleanup costs from more frequent and powerful natural disasters and lethal heat waves. Even the tiniest bit of foresight applied today could help us immeasurably in the future, so a Hothouse Earth is not a glimpse of our fate but a warning that we need to act sooner rather than later, especially when the only reason for inaction is myopic, economically and socially self-destructive ideological tribalism.

After all, the worst outcome of trying to create a more sustainable world is cleaner water and air, sustainable management of our natural resources, energy independence, fewer refugees and displaced persons, and a healthier public with a whole host of new jobs and career options to choose from as they remake the planet. Shouldn’t we aim for that even without a threat to our civilization hanging over our heads and urgently expedite these efforts when there is one? And shouldn’t we demand world leaders who aren’t lazy or downright malicious when it comes to planning for our future if our current ones are?

Politech // Climate Change / Global Warming / Science