A while back Hauke compared the effectiveness of work on climate compared to global development interventions, and wrote this post. After realising an error in the first version of the model, he reversed his initial conclusions and wrote the title that global development is generally more effective. But as he recognises in the updated introduction, some commenters identify that it's more that the confidence intervals are overlapping. Then I found this interesting paper with a different take on mortality and emissions, so I thought I'd play with the figures to see what happens.
Summary, limitations, and implications
In the workings below, I find that under baseline and realistic assumptions, it costs around $1,200 to save a life by averting carbon emissions versus $3,400 through GiveWell's health interventions. This means some work on climate change could be more effective than GiveWell's top health interventions.
I just came across this paper The Mortality Cost of Carbon by Danny Bressler,
In a baseline emissions scenario, the 2020 MCC is 2.35x10^-4 excess deaths per metric ton of 2020 emissions.
This implies that 1/0.000235 = 4,255 tons of carbon produce harm enough to reduce global health by one life in expectations. GiveWell estimates that it costs $3,373 to save a life.
Comparing this with Founders Pledge's report, if we take their lower-ranked charity (because the uncertainty range is narrower), the expected cost benefit of future projects is given below, along with the cost to avert 4,255 tonnes.
- Future pessimistic - $5.50 per tonne, so $23,400 to avert 4,255 tons
- Future realistic - $0.29 per tonne, so $1,234 to avert 4,255 tons
- Future optimistic - $0.03 per tonnes, so $127 to avert 4,255 tons
So if this is correct, it costs $3,373 to save a life via Malaria Consortium, as recommended by GiveWell, but $1,234 to save a life through abating emissions under their realistic scenario. Am I missing something here?
Limitations and implications
I realise one limitation here is that Danny's paper looks at 2020-2100, which may be a different time period to GiveWell which I expect to be benefiting people within the next decade.
But I think this is useful in expanding a broader conversation about climate change as a bridging cause, which links up both present-concern global development and also longtermism.
This also excludes the harms of air pollution, energy poverty, and ignores broader effects, e.g. astronomical stakes.