NYUAD team finds rapid melt cause of Greenland's Helheim glacier
US's Office of Polar Programmes joins NYUAD to study cause of 'unusually high melt rate' at one of Greenland's largest glaciers
Researchers from New York University Abu Dhabi’s (NYUAD) Centre for Global Sea Level Change, supported by the Office of Polar Programmes of the US's National Science Foundation, found that “unusually warm ocean water” was causing the Greenland outlet glacier Helheim, one of the largest in the region, to rapidly melt.
NYUAD’s study found that warm waters originating in the topics have been found at uniform depth for the first time, displacing cold polar water at the Helheim calving front, which is causing an “unusually high melt rate”.
UAE state news agency Wam reported that ocean waters near the terminus of an outlet glacier such as Helheim are typically “at the freezing point and cause little melting”.
On 5 August, 2019, researchers led by Professor of Mathematics at NYU’s Courant Institute of Mathematical Sciences and Principal Investigator for NYUAD’s Centre for Sea Level Change, David Holland, deployed a helicopter-borne ocean temperature probe into a pond-like opening, created by warm ocean waters, in the usually thick and frozen mélange in front of the glacier terminus.
Warm and salty waters from the tropics typically travel north with the Gulf Stream, where at Greenland they meet with cold, fresh water coming from the polar region under which they sink because they are so salty.
However, Holland and his team discovered that the temperature of the ocean water at the base of the glacier was a uniform 4°C from top to bottom at depth to 800m – a finding that was reportedly also recently confirmed by Nasa’s Oceans Melting Greenland project.
Commenting on the findings, Holland said: "This is unsustainable from the point of view of glacier mass balance as the warm waters are melting the glacier much faster than they can be replenished.
“We are surprised to learn that increased surface glacier melt due to warming atmosphere can trigger increased ocean melting of the glacier.
“Essentially, the warming air and warming ocean water are delivering a troubling ‘one-two punch’ that is rapidly accelerating glacier melt,” he added, according to Wam.