7. Siberia

Siberia  [huanqiu.com]

Occupying about 10 percent of the earth's land surface, or 12.75 million square kilometers, Siberia extends from the Ural Mountains to the strait between the Pacific and Arctic oceans.

Rich in oil and gas complexes, Siberia's pipelines, roads, and railways are all built on top of the permafrost. Rising temperatures threaten the whole structures here.