Monday, February 4, 2019

New science: methane disproportionately increases sea level

This is new to me. I had been told by scientists that carbon dioxide was absorbed by the oceans (making it more acidic) but methane was not taken up by the oceans. Technically true.  But this new research shows that methane, which leaves the atmosphere faster than CO2, affects sea level for centuries. In addition to heating up the air which affects ocean temperature, methane creates a radiative effect (like the sun on your face on a cold day) even when and if global temperature falls.
We show that short-lived greenhouse gases contribute to sea-level rise through thermal expansion (TSLR) over much longer time scales than their atmospheric lifetimes. For example, at least half of the TSLR due to increases in methane is expected to remain present for more than 200 y, even if anthropogenic emissions cease altogether, despite the 10-y atmospheric lifetime of this gas. 

https://www.pnas.org/content/114/4/657

No comments:

Post a Comment