Question

QUESTION 33 Large amounts of long-stored organic material will begin to decay and release carbon dioxide when extensive areas of: O forest grow in new regions Arctic sea ice melts. O permafrost thaw. O agriculture experience longer growing seasons.

Answer 1

Ans. Large amounts of long stored organic material will begin to decay and release carbon dioxide when extensive areas of (c) permafrost thaw.

Permafrost refers to the condition in which the associated rock and land areas remain under extremely low temperature (below 0^oC) for a period over at least consecutive 2 years. When the temperature rises, it leads to melting or thawing. The global warming is leading to enhancement in the thawing cycle. Usually the frost cycle consists of storing plant and animal organic debris beneath the layers which extend from 3- 5000 ft. It is a known fact that carbon dioxide is released when organic matter undergoes decay. Microorganisms act upon dead and decaying organisms for their metabolism or respiration and thus bring about release of carbon dioxide. Moreover, ice sheets and snow are more likely to trap carbon dioxide as bubbles due to higher the affinity of carbon dioxide to the ice sheets. During thaw period, ice melts and leads to the release of carbon dioxide.