I replied about this before to one of your posts. Maybe I did not explain it well. In short, two guys wrote a paper about how combinations of heat and humidity above certain levels could kill everyone who lacks access to air conditioning in large regions of the world, or at least force them to evacuate their countries. Do you have any opinion on the priority level of understanding this compared with other climate causes?

What do folks here think about the political views of Noam Chomsky? I ask because he is a strict global cosmopolitan thinker on foreign policy. And global cosmopolitanism is a central part of EA. Do any seasoned members of this site have an opinion?

Would whoever downvoted this like to discuss why?

Did you think this was a crank cause? No. GiveWell has mentioned this, if that helps lend it credibility. Here's a quote:

Rising temperatures could also impact human health through extreme heat waves, or cause droughts that might lead to water scarcity and decreased agricultural production.16 More extremely, we have seen it argued that a 12ºC increase in mean global temperature—which is substantially outside the range considered plausible this century—would cause at least one day each year in the territories where half of all people live today to be hot enough to exceed human metabolic limits and cause tissue damage from hyperthermia after a few hours of exposure.17

But I don't see this taken to its logical conclusion. That's what I tried to do in my e-mail that I linked to above.

I think this climate cause should be the top climate priority.

very neglected climate cause (an e-mail I wrote)

Hello Professors A and B,

Earlier this year I looked over a paper that was published in 2010 called "An adaptability limit to climate change due to heat stress”. It made a strong impression on me. I think heat stress must be the biggest danger to human beings from climate change. If a region becomes uninhabitable, or at least uninhabitable to folks too poor to afford air conditioning, that trumps everything else.

I wrote to you because I am puzzled that journalists and researchers do not seem to agree. For example in this article

https://www.vox.com/science-and-health/2017/1/9/14186328/risks-climate-change-graph

David Roberts says, "The risks of climate change are not easy to communicate clearly. Since the atmosphere affects everything, everything will be affected by its warming — there’s no single risk, but a wide and varied array of risks, of different severities and scales, affecting different systems, unfolding on different timelines. It’s difficult to convey to a layperson, at least without droning on and on.”

To me this sounds stupid. Partly this is because I am mostly concerned about the United States and a few other countries that I have some connection to. I am less concerned about saving the whale or preserving nature for its own sake. Okay, so maybe Roberts and I just disagree about values. (Explanations of social trends, let alone predictions, with many moving parts also seem suspect to me, i.e. http://slatestarcodex.com/2015/02/14/how-likely-are-multifactorial-trends/ )

But even the economic literature on climate seems flawed. I think Professor Martin Weitzman was correct in this paper when he said, "we might be underestimating considerably the welfare losses from uncertainty by using a quadratic damages function and/or a thintailed temperature distribution.”

http://docplayer.net/20146089-Ghg-targets-as-insurance-against-catastrophic-climate-damages.html That paper talks about perhaps losing 50% of GDP.

There was a study that came out this year on heat stress in the United States. It extrapolated the changes in mortality from past hot days. But if there are days unlike any we have seen before, days where the wet bulb temperature approaches or exceeds human limits, then this extrapolation is not accurate.

https://www.nytimes.com/interactive/2017/06/29/climate/southern-states-worse-climate-effects.html (flawed) http://www.sciencedirect.com/science/article/pii/S0095069611001033 (flawed) http://www.pnas.org/content/114/15/3861.short (on nonlinearity)

Also I do not see any research on future adaptation to heat stress. I did find this paper on past adaptations:

http://www.nber.org/papers/w18692

To sum up, I don’t understand why even many supposedly more pessimistic studies like the Stern Review don’t take into account heat stress at all. I don’t understand why the study that made headlines this year in the New York Times ignores the issue of the wet bulb limit. I don’t understand why more hasn’t been done on future adaptation to heat stress. I also don’t see why heat stress doesn’t have a higher profile in activist organizations trying to fight climate change and among people in the media.

I hope you can share with me your views on these questions.

Thank you,