.dropcap { color: #838078; float: left; font-size: 82px; line-height: 60px; padding: 5px 8px 0 0; } When one grasps the full implications of climate change, there comes a measure of grief. I first recognized this in May 2014, when scientists studying the massive Thwaites Glacier in Antarctica reported that it had begun a process of “unstoppable” collapse. Something collapsed in me as well. Looking back, I can see it was the loss of the idea that our environmental mistakes could be undone before it was too late. And with that, society’s actual goal became clear: to do all we can to avert the most damaging outcomes. How much can we do? The answer, I’m convinced, is quite a lot. And I have plenty of company in this conviction. Ask just about any climate scientist and you’re likely to get a straightforward answer: The faster we act, the less we suffer. Not long ago I spoke with Zeke Hausfather, who studies future temperature scenarios at Berkeley...