A large influx of freshwater into the ocean can turn off ocean currents which halts the transfer of heat from the equator to the poles. (See Shutdown of thermohaline circulation)
UCIrvine: 18 percent more water fed into the world’s oceans from rivers and melting polar ice sheets in 2006 than in 1994, with an average annual rise of 1.5 percent.
[Via Juan Cole]
