GEOLOGY

Detailed explanation-1: -About 50% of a CO2 increase will be removed from the atmosphere within 30 years, and a further 30% will be removed within a few centuries. The remaining 20% may stay in the atmosphere for many thousands of years. From U.S Greenhouse Gas Inventory Reports: Atmospheric lifetime: 50-200 years.

Detailed explanation-2: -Carbon dioxide is a different animal, however. Once it’s added to the atmosphere, it hangs around, for a long time: between 300 to 1, 000 years. Thus, as humans change the atmosphere by emitting carbon dioxide, those changes will endure on the timescale of many human lives.

Detailed explanation-3: -The lifetime in the air of CO2, the most significant man-made greenhouse gas, is probably the most difficult to determine, because there are several processes that remove carbon dioxide from the atmosphere. Between 65% and 80% of CO2 released into the air dissolves into the ocean over a period of 20–200 years.

Detailed explanation-4: -The second graph shows CO2 levels during Earth’s last three glacial cycles, as captured by air bubbles trapped in ice sheets and glaciers. Since the beginning of industrial times (in the 18th century), human activities have raised atmospheric CO2 by 50% – meaning the amount of CO2 is now 150% of its value in 1750.

Detailed explanation-5: -The present atmospheric concentration of CO 2 is the highest for 14 million years.