An iceberg floats in Disko Bay behind houses during unseasonably warm weather on July 30, 2019 in Ilulissat, Greenland. Climate change is having a profound effect in Greenland, where over the last several decades summers have become longer and the rate that glaciers and the Greenland ice cap are retreating has accelerated.

The historic heatwave that scorched Europe last week has moved to Greenland, where it's expected on Thursday to melt away 12 billion tons of water from the ice sheet and irreversibly raise sea levels across the world.

The heat is causing one of the largest melt events ever for Greenland, following a record event in 2012 where 97% of the ice sheet experienced melting. This week, over 60% of Greenland's surface was melting, according to computer model simulations, with temperatures over 25 to 30 degrees Fahrenheit higher than normal.

The higher frequency of extreme melt events has serious consequences for coastal communities across the world, climatologists warn.

Greenland is the biggest contributor to sea level rise, which threatens to destroy property value in coastal regions, displace residents and eventually impact global markets.

"What we're seeing in Greenland is exceptional. It's a wake up call," Penn State climatologist Luke Trusel said. "What we do now is critically important."

If all of Greenland's ice melted, global sea levels would rise over 20 feet. This week's melt alone is estimated to permanently raise global sea levels by 0.1 millimeters.

While that measurement may seem small, this week's melt is not an isolated event. Climate models estimate a sharp increase in frequent extreme weather events and longer periods of above average temperatures across Greenland. So, several hundred isolated weather events stacked up over the next 30 years, for instance, translates to multiples inches of sea level rise across the globe.

"The fact that we are getting measurable sea level rise out of a single day of melt is shocking," said meteorologist Eric Holthaus. "There are real and lasting consequences from this single heat wave that will last for thousands of years."

In June alone, Greenland's ice sheet lost 80 billion tons of ice, according to the National Snow and Ice Data center. In July, the ice sheet lost 160 billion tons of ice. This week, Greenland will lose over 50 billion tons of ice, according to estimates.

"You can't undo these melt events," said Brian Brettschneider, a climatologist at the University of Alaska Fairbanks' International Arctic Research Center. "The only way is to freeze it, and that's just not possible given the trajectory we're on."

Global sea levels will rise 2 to 6 feet by 2100 on the current trajectory, according to satellite data. However, given that greenhouse gas emissions are rising and global warming is accelerating at an unprecedented pace, scientists argue that the current projections underestimate sea level rise.