This is a brief note for those who might be interested of reducing their net CO2 emissions.
Cool Earth (a charity protecting rainforests) can reduce emissions by 1 tonne CO2-equivalent (by protecting rainforest which stores CO2 and which, if logged, would release huge amounts CO2) per around 1.5$ dollars donated [1].
To compensate for San Francisco – Bali flight ~ 3 tonnes CO2 [2] => donate 4.5$
To compensate for a year of eating meat ~ 1.6 tons CO2 [3] => donate 2.4$
It seems fairly cheap!
https://www.coolearth.org/get-involved/donate-cool-earth/
[1] https://www.givingwhatwecan.org/report/cool-earth/
These numbers are a bit old – from 2016 – but as far as I can tell they have the right order of magnitude.
“We estimate that Cool Earth is able to reduce emissions by 1 tonne of CO2-equivalent for every $1.34 donated, for directly protected forest specifically (although this figure may be as low as $0.65). If indirectly shielded forest is also included, this drops to $0.38 per tonne of CO2-equivalent”
[2] CO2 emissions flying:
101g / (1 passenger-km) (http://www.carbonindependent.org/sources_aviation.html)
x 13,410.05 km (https://www.distance.to/Bali/San-Francisco) = 1.354kg one way, or 2.708kg return, i.e roughly 3 tonnes
[3] CO2 emissions due to eating meat:
“GHG emissions in kilograms of carbon dioxide equivalents per day (kgCO2e/day) were 7.19 (7.16, 7.22) for high meat-eaters,.. for vegetarians and 2.89 (2.83, 2.94)”
(https://www.ncbi.nlm.nih.gov/pmc/articles/PMC4372775/)
(7.19 – 2.89) x 365 = 1570 kgCO2e/year ~ 1.6 tonnes