The world is home to 117 million lakes, according to a satellite-based survey.
Lakes are important to the planet's carbon cycle, but researchers have struggled to estimate the number that exist, in part because small lakes have been difficult to count. A team led by Charles Verpoorter of the University of Lille Nord in France used high-resolution imagery from the Landsat satellite to catalogue all lakes larger than 2,000 square metres.
Unlike earlier estimates, the total count is dominated by large and medium-sized lakes, not small ones. Together, the lakes cover about 5 million square kilometres, or 3.7% of Earth's land not covered by ice.
Geophys. Res. Lett. http://doi.org/t9v (2014)