> But hopefully I’ev misunderstood something. I am and have been what might be called a 'climate change alarmist' for decades now. More concretely, I believe

> But hopefully I’ev misunderstood something. I am and have been what might be called a 'climate change alarmist' for decades now. More concretely, I believe that there's a non-trivial chance that the climate will, in the lifetimes of people reading this, become hostile toward our civilization, as it stands today. These considerations have come from deep and wide personal studies on relevant topics. Human extinction is exceedingly unlikely, even in the worst possible cases. Many deaths (where 'many' means 'substantial percentages of some populations') are possible, though hopefully still unlikely. Things will change. A lot. Even though who are well read on the topic will find it impossible to characterize those changes. We are introducing tremendous amounts of additional energy into our climate, which increases variance and especially uncertainty. But even given all that, extinction is exceedingly unlikely.