15 October 2018

Large Regional Shortwave Forcing by Anthropogenic Methane Informed by Jovian Observations

Methane also heats the climate system by absorbing sunlight, and the absorption is maximized over bright clouds and deserts.

Science

Methane also heats the climate system by absorbing sunlight, and the absorption is maximized over bright clouds and deserts.  

Impact

These findings about the effect of methane on incoming solar energy are useful for understanding the historical climate record and future projections, first by updating the relative strengths of the radiative forcing due to carbon dioxide and methane, and second by highlighting the relative susceptibility of different regions across the world to climatic effects of methane.

Summary

Scientists investigating how human-induced increases in atmospheric methane also increase the amount of solar energy absorbed by that gas in our climate system have discovered that this absorption is 10 times stronger over desert regions such as the Sahara Desert and Arabian Peninsula than elsewhere on Earth, and nearly three times more powerful in the presence of clouds. A research team from the Lawrence Berkeley National Laboratory came to this conclusion after evaluating observations of Jupiter and Titan (a moon of Saturn), where methane concentrations are more than a thousand times those on Earth, to quantify methane’s shortwave radiative effects here on Earth.

Contact
William D. Collins
Lawrence Berkeley National Laboratory (LBNL)
Publications
Collins, W, D Feldman, C Kuo, and NH Nguyen.  2018.  "Large Regional Shortwave Forcing by Anthropogenic Methane Informed by Jovian Observations."  Science Advances 4(9): eaas9593, doi:10.1126/sciadv.aas9593.