The international group of researchers has discovered that the melting Greenland shield releases the same mercury as the industrial rivers of China. As scientists write in the article published in the Nature Geoscience magazine, heavy metal can fall into food chains, which represents a threat to fisheries and seafood exports.
Researchers estimated the amount of mercury, falling into a thawed water in fjords with three glacier catchments on the south-western outskirts of the Greenland glacier shield. It turned out that the concentration of metal reaches 521-3300 Millimol per square kilometer per year, which is two orders of magnitude higher than in the Arctic rivers (4-20 millimol per square kilometer per year). Dissolved mercury flows from the south-western region of Greenland are about 10 percent of the global river stream and include the export of methylratuti – the most toxic mercury-containing compound, accumulating in the body of animals.
The source of mercury is likely to be a natural source hiding under the glacial cover, that is, it is not about the result of human activity. At the same time, the glaciers are melting due to global warming, which may make it difficult to reduce heavy metal emissions into the environment. About 10 percent of the surface of the earth is covered with glaciers, and this environment undergoes rapid changes as a result of increasing global average temperatures.