Oceans warmed in recent decades

Earth’s upper ocean warmed substantially between 1993 and 2008, a new analysis reveals. The trend signals growing heat storage in oceans, researchers say, a result of human-caused warming.

The new study, reported in the May 20 Nature, combined oceanographic data gathered worldwide between 1993 and 2008, the time period with the most data available. During that period, the upper 700 meters of the world’s ocean warmed on average by about 0.18 degrees Celsius, says John M. Lyman, a physical oceanographer with the National Oceanographic and Atmospheric Administration in Seattle.