While high temperatures were critical to the melting seen in Greenland last year, scientists say that clear blue skies also played a key role.
In a study, they found that a record number of cloud free days saw more sunlight hit the surface while snowfall was also reduced.
These conditions were due to wobbles in the fast moving jet stream air current that also trapped heat over Europe.
As a result, Greenland’s ice sheet lost an estimated 600 billion tonnes.
Current climate models don’t include the impact of the wandering jet stream say the authors, and may be underestimating the impact of warming.
In recent weeks, an analysis of last year’s melting said the 600 billion tonnes of ice added 2.2mm to global sea levels in just two months.
This new study says that while rising global temperatures played a role in the events last year, changes in atmospheric circulation patterns were also to blame.
Researchers found that high pressure weather conditions prevailed over Greenland for record amounts of time.
They believe this is connected to what’s termed the “waviness” in the jet stream, the giant current of air that mostly flows from west to east around the globe.
As the current becomes more wobbly, it bends north, and high pressure systems that would normally move through in a few days become “blocked’ over Greenland.
These systems had different impacts depending on the part of Greenland you were in.