Most marine organisms are adapted to the ocean’s salt concentration. Just as humans cannot drink saltwater, plankton and other small marine creatures floating with the currents cannot survive in fresh water. These organisms form the base of the arctic food chain. If they die, the small fish that feed on them die. Larger fish and mammals that feed on the small fish also lose their food source. Even the mighty polar bear would be at risk of starvation. The freshwater lake could have an even larger impact on Earth’s climate if it emptied into the North Atlantic quickly. Ocean currents that move heat around the globe are sensitive to saltwater concentrations. Because fresh water floats on top of saltier water, a large influx of fresh water could slow the currents and alter temperature and weather patterns. At the present time, the arctic lake’s size is equivalent to the amount of fresh water the Atlantic receives in a year. It isn’t a threat to global climate now, but it’s an important lake for scientists to watch.