Re:In a warming world, New England’s trees are storing more ...
by vnorilo on Wednesday August 05, 2020 @04:35AM
(#24058532)
Thank you for the well-argued and rational post. To me, buying 20 years for decarbonization sounds kind of great. So, it's a fallacy to think we could just plant trees and otherwise go on as usual. We just need to be careful about language that might feed into defeatism: planting a lot of trees is not a wasted effort, it's a great thing to do. Yes, we need to do a lot more, but every year of extra time helps a lot.
If you expand forests it's a one-time sequestration. That's my point.
> One doesn’t count rainforests or boreal forests as “zero carbon” capture. They have an ongoing capturing capacity.
Each ecosystem has a turnover time. For rainforests it's like 20 years. For tundra it's as long as 65+ years. But in a stable state these carbon "sinks" are net zero carbon capture. For every ton of carbon they capture, a ton of carbon is released through decomposition.
A recent study published in 2019 said that if total emissions, agricultural land use, and other factors remained steady, planting trees might buy us 20 years: https://climate.nasa.gov/news/2927/examining-the-viability-o...
The problem is that we're pumping out alot of carbon: about 10GtC/year. The entire Amazon rainforest sequesters only about 100-200GtC. Actually, the biggest problem as I said is that we're pumping out carbon from a resource (Carboniferous period deposits[1]) that can never again be recreated, at least not without significant geoengineering.
[1] Carboniferous deposits occurred at a golden period, immediately after woody trees first emerged, but before microorganisms evolved that could decompose them; trees could be buried long enough to fossilize before microorganisms could release all the carbon back into the atmosphere. That can't happen today naturally, at least not at any scale that could help us.