Free Astronomy Magazine January-February 2022

28 JANUARY-FEBRUARY 2022 ASTRO PUBLISHING T o what extent is the increase in greenhouse gas levels in the atmosphere attributable to human activities? Nobody knows exactly and, depending on the time frames considered and the economic interests at stake, the estimates vary incredibly from a few percentage points to 100%. The contradictions in the data are there for all to see, and it is likely that the answer lies somewhere in between. It is estab- lished that, since the beginning of the industrial revolution (second half of the 1700s), the concentration of atmospheric carbon dioxide (CO 2 , the most famous but not the most dangerous greenhouse gas) has grown by 48% (NASA). Likely, this value also includes a greater contri- bution by the main natural sources of atmospheric carbon dioxide: de- gassing of the oceans, decomposi- tion of biomass, volcanic activity, forest and wood fires, respiration of organisms, alteration of carbonate The Earth doesn’t give a damn about global warming by Michele Ferrara revised by Damian G. Allis NASA Solar System Ambassador A n emblematic image of the presence of a harmful animal species on a previously heavenly planet. [David McNew/Getty Images]