This happened as the temperatures at the Greenland Summit rose above freezing for the third time in less than a decade, reported CNN.

It was the heaviest rainfall since the climate and weather record keeping for the polar island began in 1950.

The warm air triggered an extreme rain event that dumped 7 billion tons of water on the ice sheet, enough to fill the Reflecting Pool at the National Mall in Washington, DC, nearly 250,000 times, stated the CNN report.

Ted Scambos, a senior research scientist at the National Snow and Ice Data Center at the University of Colorado, said this is evidence Greenland is warming rapidly.

"What is going on is not simply a warm decade or two in a wandering climate pattern," Scambos told CNN. "This is unprecedented."

"Increasing weather events including melting, high winds, and now rain, over the last 10 years have occurred outside the range of what is considered normal," Jennifer Mercer, program officer for the Office of Polar Programs at the National Science Foundation said. "And these seem to be occurring more and more."

As climate change induced by human activities warms the planet, ice has melted at a rapid rate. A UN climate report released, earlier in August, concluded that fossil fuel burning has led to Greenland melting over the last 20 years.

In July, the Greenland ice sheet witnessed one of the most significant melting events, shedding more than 8.5 billion tons of surface mass in a single day, which was enough to submerge entire Florida in two inches of water.