Two Billion People at Risk of Losing Water Supplies Due to Snowpack Loss

Roughly 2 billion people are at risk of declining water supplies in the northern hemisphere due to decreasing snowpack, according to researchers at Columbia's Lamont-Doherty Earth Observatory.  Snow is an important seasonal water source in mountainous regions because it melts and runs gradually toward lowland drainage basins during spring and summer, when human demand is at its peak.  Researchers identified 97 basins with at least a two-thirds chance of declining water supplies, ranging from productive U.S. farmland to war-torn regions already in the grip of long-term water shortages. Nearly 1.45 billion people rely on snowpack in just 32 of those basins for a substantial proportion of their water.  Among them are the basins of northern and central California, where much of U.S. produce is grown; the basins of the Colorado and Rio Grande rivers, which serve much of the American West and northern Mexico; the Atlas basin of Morocco; the Ebro-Duero basin, which feeds water to Portugal and much of Spain and southern France; and the volatile Shatt al Arab basin, which channels meltwater from the Zagros Mountains to Iraq, Syria, eastern Turkey, northern Saudi Arabia, and eastern Iran.

Read more at Declining Snowpacks May Cut Many Nations' Water