Answer: The release of methane from thawed permafrost
Explanation:
With increasing global warming, permafrost in the arctic is melting. The carbon and methyl clathrates present in permafrost escape into the atmosphere to form carbon dioxide and methane, both greenhouse gases.
In the Arctic, molecules of methane are trapped in ice crystals as methyl clathrates. When the temperature increases, these crystals release methyl clathrates which become methane when in contact with the atmosphere.
The cause of the increasing atmospheric 
is due to the the thawing of dead organisms present in the permafrost. As the permafrost melts, these organisms decay and release into the atmosphere.
The increase in number of people
Explanation:
are tectonic earthquake in one that occurs when the earth crust death due to geological forces on Rock and adjoining place that cause physical and chemical changes volcanic earthquake is any earthquake that results from tectonic forces which occurs in conjunction with volcanic activity .
Answer:
Towns grew up along the rivers which had access to the sea. Rivers also provided protection from invaders. Farmers grew crops in the fertile fields that surrounded the towns. The lack of mountains was good for farming, but it made the towns easier to be invaded by enemies.
Explanation:
Answer:true
Explanation: Seventy-five percent of Canada's population resides in a narrow 150-kilometre band pushing up against the U.S., with close ties south of the line.
