Scientists fly over Greenland on mission to track melting ice
The fields of rippling ice 500 feet below the NASA plane give way to the blue-green of water dotted with irregular chunks of bleachedwhite ice, some the size of battleships, some as tall as 15-story buildings.
Like nearly every other glacier on Greenland, the massive Kangerlussuaq is melting. In fact, the giant frozen island has seen one of its biggest melts on record this year. NASA scientist Josh Willis is now closely studying the phenomenon in hopes of figuring out precisely how global warming is eating away at Greenland’s ice.
Specifically, he wants to know whether the melting is being caused more by warm air or warm seawater. The answer could be crucial to Earth’s future.
Water brings more heat to something frozen faster than air does, as anyone who has ever defrosted a steak under the faucet knows.
If Willis’ theory that much of the damage is from the water turns out to be correct, he said, “There’s a lot higher potential for Greenland to melt more quickly than we thought.” That means seas rising faster and coastal communities being inundated more.
Greenland contains enough ice to make world sea levels rise by 20 feet if it were all to melt. In a single day this month, it lost a record 13.7 billion tons by one estimate.
“It’s a little scary,” Willis said as looked down on an area filled with more water than ice. “We’re definitely watching the ice sheet disappear in front of us.”
Climate change is eating away at Greenland’s glaciers in two ways. The most obvious way is from the warm air above, which has been brutal this summer, with a European heat wave in July working like a hair dryer on the ice. The other way is from warm, salty water, some of it from North America’s Gulf Stream, nibbling at coastal glaciers from below.
Willis’ project — called Oceans Melting Greenland, or OMG — is showing that it is. Now the question is how much and how fast.
Willis is measuring the water 660 feet or more below the surface, which is warmer and saltier than the stuff that touches the air. This deep water does the major damage.
To measure this, NASA is spending five years crisscrossing the island in a trickedout 77-year- old DC-3 built for World War II. Long, cylindrical probes are dropped through a special tube in the floor of the plane, parachute down and dive into the chilly water, measuring temperature and salinity.