Comment by eggy
Comment by eggy 4 days ago
If it has been underestimated then that means climate models have been using the bad, underestimated data, so they need to be updated and run to see where we are at, corrrect?
Comment by eggy 4 days ago
If it has been underestimated then that means climate models have been using the bad, underestimated data, so they need to be updated and run to see where we are at, corrrect?
That's a straw man.
I expect climate models contain a lot of parameters that aren't related to plant uptake of CO2, and some that are. I expect that, until now, the latter have been based on the 1980 study, because otherwise this latest result would not be news.
I also expect that the contribution of plant CO2 uptake is a large factor in these models, so a significant change like this will potentially have a significant effect on predictions.
Are any of these expectations wrong? If so, which ones?
Yes because the models attempt to model feedback loops like the albedo difference created by greenery, the CO2 dampening effect of photosynthesis, the water content of the air and how that's affected by trees and so on.
Bear in mind, ESMs aren't trying to predict future CO2 levels. They're trying to predict future weather based on the effects of higher CO2, and vegetation is a part of that.
Right, this new estimate can be useful for decision support: if we plant X acres, how much CO2 would it absorb? It's not very important outside of that, and it cant have caused significant past errors because to date humans have not undertaken large-scale planting for CO2 absorption reasons.
Several countries have implemented large-scale planting efforts: China, Ethiopia, India, Brazil, Australia, Pakistan, and Turkey to name a few. In 2019, Ethiopia claimed to have planted over 350 million trees in a single day as part of a broader initiative to plant 4 billion trees within a year to fight climate change.
>It's not very important outside of that,
It's not very important outside of predicting the future of the climate accurately.
That's not the kind of thing I'd write "It's not very important outside of" before. This "mere" prediction and decision support is the reason we fund the sciences.
Expected future CO2 concentration are a parameter for the climate models, and are generated by themselves by other models with different set of inputs accounting for a series of natural and socio-economic variables.
Don't we need models to make predictions about the future?
Yes, although you will not find a climate scientist that will admit to having used a model that was clearly wrong. They just silently update the model and hope you don't ask. And if you ask, nope, they will not hand over their model. But trust me bro, the models are correct.
No. Climate scientists did not base all of their current models on a 1980 study about how much CO2 trees can technically absorb.