A new satellite study finds that Greenland lost 586 billion tons of ice in a record melt last year.
That's 140 trillion gallons of water or enough to cover all of California in more than four feet of water.
Thursday's study says it's due to a combination of climate change and an occasional weather effect that sends warm air from North America into Greenland instead of cooler Arctic air.
In 2017 and 2018, Greenland had lower than average melt summers because the air was coming from the Arctic.
But overall Greenland has been losing nearly 260 billion tons of ice a year since 2003.
