It has come to my attention that the usual suspects are engaging in a huge publicity campaign for a new book of racist colonialist propaganda by @AlexEpstein. Sadly, the book is being published by @penguinrandom .

Some thoughts below in a long thread: 🧵 1/n Recent centuries have seen unprecedented improvement in human welfare in the developed world. In 1800 more than 80% of humanity lived below the International poverty line of $2/day (constant dollars), but now fewer than 10% of people worldwide live in such desperate straits 2/n

Annual birthday pilgrimage to our cabin near treeline on the occasion of the opening of the paved road (road to cabin won't open until July).

Peak snowpack was a little below average & is 80% melted, but easy to forget that average is A LOT! Front door and window of the cabin two days ago. (Luckily the back door was blown clear)

Living with Ambiguity in a Nonbinary Climate
(presenting this evening at Yale School of the Environment)

🧵(a thread)
1/n 2/n

🧵LONG THREAD
Thinking about climate econ for my class!

Unabated climate change is already causing massive disruptions. It will get worse till we stop making it worse, then stay bad for centuries.

By how much might this slow economic growth?
0.01%/yr?
0.1%/yr?
0.5%/yr?

1/18 Consider two cases: "cool" (with abatement) and "hot" (without abatement).

With abatement, global income grows as
G(t) = G0 exp(rcool * t)

Without abatement, global income grows as
G(t) = G0 exp(rhot * t)

Just for grins, let's assume rcool = 2.5%/yr and rhot = 2.4%/yr.

2/18

🧵Thread on the "Failing Amazon Carbon Sink" paper by Gatti et al last week.

Nutshell: Amazon has been a carbon sink for decades; now it's switching to a carbon source.

Gatti et al tracked CO2 & CO in AIR ITSELF to measure regional CO2 balance. 1/n
go.nature.com/3hBndYi Dave Keeling invented a precise IR gas analyzer in the 1950s. He installed one in Hawaii & one at South Pole.

By 1960 he'd shown that (1) CO2 is rising; (2) rate of increase is only ~50% of fossil fuel combustion; and (3) there's a seasonal cycle driven by NH vegetation.

2/n

THREAD: We can't afford NOT to decarbonize the world economy

Economists estimate the total cost of decarbonizing the world economy to be about 1% of global GDP.

Stern Review of Climate Change Economics (2006)

1/n

en.wikipedia.org/wiki/Stern_Rev… Like other experts, economists argue about this number. But 1% of global GDP is a robust ballpark #. Nobody thinks it will be free and nobody thinks it will be 5% of GDP.

William Nordhaus won the 2018 Nobel Prize in Economics for this kind of work.

2/n

nobelprize.org/prizes/economi…