Snowmageddon in Washington, D.C. Extreme floods in the United Kingdom last winter. A Texas heat wave two years ago. For scientists, they all may be a byproduct of a warming Arctic. Or they might not, as much of the research on causation is still in early stages. A new review article, released yesterday in Nature Geoscience, offers one additional theory about the link between the Arctic and extreme weather in midlatitudes, pointing to a possible connection between snow in Siberia and unusual events in much of the United States, Europe and East Asia. But ultimately, the synthesis paper reports that much of the science remains uncertain about the link, as there is contradictory evidence for all of the main theories.