Russian and German scientists explore the Arctic's Laptev Sea and its climate system

River runoff into the Laptev Sea in the Siberian Arctic (Figure 1) causes dramatic environmental changes in the sea, influencing not only the entire Arctic climate but global climate as well, a 4‐year study suggests. The study, known as the Laptev Sea System program, was conducted by a joint group of Russian and German scientists. It marked the first time a major comprehensive research program looked at the extreme environmental system of the Laptev Sea, addressing both oceanic and terrestrial processes. The work focused on mechanisms involved in past and ongoing climate variations in the Laptev Sea region (Figure 2) with an emphasis on the interaction between the sea and the Lena River in the summer, autumn, and spring. In the summer, river water spreads over the sea as a low‐salinity surface layer carrying much of the river's suspended load. In the fall, during ice formation, the low‐salinity layer controls the fast‐ice edge and, consequently, the Laptev Sea polynya or ice clearing.