mercury in the tundra

No, not about being cold.

This article says that the arctic permafrost contains insanely high levels of mercury. On the order of two-thirds the total free mercury on the earth’s surface.

This could be bad. Currently, all that mercury is locked up in the ice. If the permafrost thaws too much, a lot of that will enter the global mercury stream. It is not clear how much of an increase our global ecosystems can tolerate.

This could be really quite bad.

Can’t all the fancy schmancy scientists figure a way to contain it?

Naw; they’re all too busy generating fake news about climate warming don’t 'cha know.

is it elemental mercury, or organic compounds like methyl/dimethylmercury?

while you definitely don’t want metallic mercury running amok, the organic compounds are seriously bad news.

WaPo says that a lot of it is atmospheric uptake by plants during the brief growing season. Since it is in the soil, I am guessing it is cast off by metabolic processes, so it is probably more elemental than in compounds. The article suggests that the source is pollution, i.e., caused by humans. ISTR burning coal puts a lot of mercury into the air.

From the article: