4 ms·
I'm sorry but I think you're missing a lot in your assumptions. For example, there are only rough estimates on how much methane is trapped in the permafrost. T
by pier25 4y ago
I'm sorry but I think you're missing a lot in your assumptions.
For example, there are only rough estimates on how much methane is trapped in the permafrost. The first estimate I saw by Natalia Shakhova et al was 1400gt over a decade ago (so about 45 years of human emissions at the current rate). I found this recent MIT article which mentions 1500gt [1]. Let's not forget methane has a 25x more heat trapping capacity than CO2. Do the math on that. Also the permafrost is just one of many feedbacks.
Another point you're not considering is that the capacity of the biosphere to absorb carbon is being reduced. For example, the Amazon used to be considered a carbon sink but it is becoming a carbon source [2].
[1] https://climate.mit.edu/explainers/permafrost https://climate.mit.edu/explainers/permafrost
[2] https://www.nature.com/articles/d41586-021-01871-6 https://www.nature.com/articles/d41586-021-01871-6
- biotinker 4y agoYou're right about methane; that's much more difficult to find data on, though, especially with regard to how much would be released and at what point. But if those tipping points get hit, then nothing CO2 related will save us. Feedback loops here dying down I'll classify under the "hope they're included in the miracle that gave us zero carbon emissions" :) I'm not convinced on your second point; I'll need to see more data. I read the paper you linked, it doesn't give hard numbers, so it's difficult to compare the net loss of carbon flux in the amazon, to gain of carbon flux in other areas that are getting net-reforested, such as the eastern United States. Examples of local areas flipping from sink to source, and others becoming larger sinks, don't paint a clear picture of the directionality of the whole system.