The climate apocalypse is coming. To prepare for it, we need to admit that we can’t prevent it.
Illustration by Leonardo Santamaria
…Our atmosphere and oceans can absorb only so much heat before climate change, intensified by various feedback loops, spins completely out of control. The consensus among scientists and policy-makers is that we’ll pass this point of no return if the global mean temperature rises by more than two degrees Celsius (maybe a little more, but also maybe a little less). The I.P.C.C.—the Intergovernmental Panel on Climate Change—tells us that, to limit the rise to less than two degrees, we not only need to reverse the trend of the past three decades. We need to approach zero net emissions, globally, in the next three decades.
This is, to say the least, a tall order. It also assumes that you trust the I.P.C.C.’s calculations. New research, described last month in Scientific American, demonstrates that climate scientists, far from exaggerating the threat of climate change, have underestimated its pace and severity. To project the rise in the global mean temperature, scientists rely on complicated atmospheric modelling. They take a host of variables and run them through supercomputers to generate, say, ten thousand different simulations for the coming century, in order to make a “best” prediction of the rise in temperature. When a scientist predicts a rise of two degrees Celsius, she’s merely naming a number about which she’s very confident: the rise will be at least two degrees. The rise might, in fact, be far higher.
As a non-scientist, I do my own kind of modelling. I run various future scenarios through my brain, apply the constraints of human psychology and political reality, take note of the relentless rise in global energy consumption (thus far, the carbon savings provided by renewable energy have been more than offset by consumer demand), and count the scenarios in which collective action averts catastrophe. The scenarios, which I draw from the prescriptions of policy-makers and activists, share certain necessary conditions.
The first condition is that every one of the world’s major polluting countries institute draconian conservation measures, shut down much of its energy and transportation infrastructure, and completely retool its economy. According to a recent paper in Nature, the carbon emissions from existing global infrastructure, if operated through its normal lifetime, will exceed our entire emissions “allowance”—the further gigatons of carbon that can be released without crossing the threshold of catastrophe. (This estimate does not include the thousands of new energy and transportation projects already planned or under construction.) To stay within that allowance, a top-down intervention needs to happen not only in every country but throughout every country. Making New York City a green utopia will not avail if Texans keep pumping oil and driving pickup trucks.