AP BIOLOGY

Detailed explanation-1: -Permafrost is soil that is permanently frozen. Permafrost is a permanently frozen layer on or under Earth’s surface. It consists of soil, gravel, and sand, usually bound together by ice. Permafrost usually remains at or below 0°C (32ºF) for at least two years.

Detailed explanation-2: -When permafrost is frozen, plant material in the soil-called organic carbon-can’t decompose, or rot away. As permafrost thaws, microbes begin decomposing this material. This process releases greenhouse gases like carbon dioxide and methane to the atmosphere.

Detailed explanation-3: -Permafrost-the permanently frozen ground that underlies much of the Arctic land surface-is thawing in many parts of the Arctic. [1] As permafrost thaws, it releases the powerful greenhouse gas methane into the atmosphere, which contributes to further warming in a reinforcing feedback loop.

Detailed explanation-4: -Just as a puddle of water freezes on a frigid winter night, water that is trapped in sediment, soil, and the cracks, crevices, and pores of rocks turns to ice when ground temperatures drop below 32°F (0°C). When the earth remains frozen for at least two consecutive years, it’s called permafrost.

Detailed explanation-5: -In particular, part of the Arctic Ocean sea floor around the North Pole is frozen. This submarine permafrost was formed more than 11, 000 years ago during the Ice Age in regions that were on the surface and were buried under water at the end of the glaciation. The evolution of permafrost during the 21st century.