This is an image of a "sinkhole" apparently created by (1) collapsing permafrost, and (2) escaping methane gas (but,
as the narrator notes, this is a new area of scientific research, and how the sinkholes are formed by rising temperatures is not entirely understood). Methane is a crucially important variable for understanding arctic climate-change, and you can find various instructive videos on this topic created by members of
the Arctic Methane Emergency Group (AMEG).
From
the same video, this shows an apartment building (in the Russian Arctic) that partially collapsed, as it was built on permafrost that has, now, melted.
This oil-pipeline was built on permafrost (and, presumably, it was made in a straight line), but is now somewhat lumpy and curving, on a verdant field.
If you're wondering why methane has a unique significance (above and beyond carbon dioxide) and why so much interest is focused on the Russian Arctic (rather than the Canadian arctic), take a look at the introductory lectures provided by David Wasdell, on Youtube,
here. For an 8 minute interview with a researcher directly engaged with the issue (i.e., of methane in Siberia, specifically) take a look at this video of Natalia Shakhova,
here.
