The world's lakes are warming at a faster rate than oceans and atmosphere, a trend that may already have triggered major changes in aquatic ecosystems, according to a new report published in Geophysical Research Letters on Wednesday. Globally, lakes have been heating up an average of 0.34°C (.61°F) per decade between 1985 and 2009, researchers found. In northern climates, the deepest ice-covered lakes are warming at twice the rate of the atmosphere.