The mission performed the most complete survey of the seafloor around Greenlands shoreline, including dozens of formerly uncharted fjords (cliff-lined inlets blocked with icebergs from breaking down glaciers), and measured how the ocean temperature level altered from place to place, year to year, and top to bottom. More than 220 glaciers flow from Greenland into the ocean. Around Greenland, the top layer of the ocean is exceptionally cold and not very salty, including a lot of water from the Arctic, the freshest of oceans. Researchers understood that about a 3rd of Greenlands glaciers account for half of its ice loss; OMG discovered that all of these culprits reach down into warm water. She and Ian Fenty, an OMG co-principal private investigator at JPL, established a job that benefits both marine biologists and oceanographers: a research study cruise to position OMG probes and acoustic sounders that record the presence of narwhals in front of West Greenland glaciers.
OMGs six-year field project in Greenland has changed researchers understanding of how fast the global sea level will increase in coming years. Credit: NASA/JPL-Caltech
The objective carried out the most total study of the seafloor around Greenlands shoreline, including lots of formerly uncharted fjords (cliff-lined inlets obstructed with icebergs from disintegrating glaciers), and measured how the ocean temperature level changed from place to location, year to year, and leading to bottom. To get this unique dataset, mission airplanes logged adequate air miles around and over Greenland to circle the world more than 13 times.
Preparation
More than 220 glaciers flow from Greenland into the ocean. Before OMG, researchers figured the ocean water swirling around and under these glaciers needed to be contributing to their ice loss. But just how much?
Satellite observations of sea surface area temperature level werent much aid in answering that question. Around Greenland, the top layer of the ocean is incredibly cold and not really salted, including a great deal of water from the Arctic, the freshest of oceans. A shallow glacier that just touches this layer melts slowly. Hundreds of feet below, the ocean is warmer and saltier. An ingrained glacier is gnawed by the warmer water, losing ice four or 5 times as quick as a shallow one.
NASAs Gulfstream III was one of numerous research study airplane that OMG used during the objectives six-year field campaign. Airports in Greenland, Iceland, and Norway acted as bases for research flights. Credit: NASA/JPL-Caltech
The only method to discover out any glaciers threat is to go to Greenland and measure the seafloor and the glacier and water in front of it. Researchers had been studying private glaciers that method for years, however Josh Willis, primary detective of OMG at NASAs Jet Propulsion Laboratory in Southern California, desired to get the total picture: to determine all 220-plus glaciers for 5 years– the length of time readily available to objectives moneyed by NASAs Earth Ventures air-borne research program.
Willis said. NASA even allowed them a 6th year of fieldwork to observe unanticipated, quick swings in water temperature levels off Greenlands west coast.
Operation
The objectives first task was to map the seafloor around the island to see where deep, warm water can reach glaciers. A specialist completed the majority of the mapping utilizing a research boat, and OMG Deputy Principal Investigator Eric Rignot of JPL and the University of California, Irvine led smaller sized surveys in following years to fill out missing out on areas.
To determine the ocean temperature level and salinity down to the seafloor, Willis ran a summer air-borne campaign that dropped about 250 probes each year into the ocean at tactical places around the whole shoreline. 6 summers of flying over the remote Arctic might sound more like an adventure than a research study task, however, Willis stated, “Its only an experience in retrospect. While youre in it, you have your head down and youre working as hard as you can.” For the scientists, the information streaming into their computer from the probes was excitement enough.
The detailed maps and temperature level data gathered by OMG show that two to four times as numerous glaciers being in water that is several degrees warmer than previously believed and, hence, are at higher danger than anyone knew. Scientist comprehended that about a 3rd of Greenlands glaciers account for half of its ice loss; OMG discovered that all of these perpetrators reach down into warm water. Environment models that do not represent the warm waters results undervalue glacial ice loss by a minimum of a factor of 2– simply put, missing out on half the water level rise from this source.
Collaboration
OMGs innovative information has affected lots of kinds of Arctic research studies besides oceanography. Kristin Laidre of the University of Washington is a globally known expert on narwhals, Arctic whales with a tusk-like protruding tooth. She and Ian Fenty, an OMG co-principal investigator at JPL, established a project that benefits both marine biologists and oceanographers: a research study cruise to place OMG probes and acoustic sounders that tape-record the presence of narwhals in front of West Greenland glaciers.
The probe information supplies a close-up view of how much ocean conditions can differ in a little location, and Laidre hopes that, in combination with the sounder data, it will assist describe why specific glacier fronts are particularly appealing to narwhals. “We biologists can get a much better understanding of animals and populations by dealing with physical researchers,” she stated, describing the OMG group. “To have a group of scientists who wish to collaborate is actually fantastic.”
Extension
The end of the objective doesnt indicate the end of all new data from the Greenland ocean. In 2021, the team dropped a few longer-lived probes in areas where changes in ocean temperatures or circulation are not completely understood. These probes “winter season over” listed below the surface, continuing to bob up and down through the water to gather information that will be checked out from another location when the ice melts next summertime.
And researchers in lots of fields will continue to make use of OMGs observations for their research. To date, about half of peer-reviewed journal posts utilizing the data are composed by researchers outside the objectives science group– an uncommonly big portion. “Were seeing a lot more science than we initially planned,” Willis stated. “Those papers arent going to stop.”
NASAs Oceans Melting Greenland airborne mission found that Greenlands glaciers that empty into the ocean, like Apusiaajik Glacier revealed here, are at higher danger of quick ice loss than formerly understood. Credit: NASA/JPL-Caltech
To discover how ocean water is melting glaciers, NASAs Oceans Melting Greenland objective thoroughly surveyed the shoreline of the worlds biggest island.
The most essential thing to bear in mind about NASAs Oceans Melting Greenland mission, which ended Dec. 31, 2021, may be its name: OMG showed that ocean water is melting Greenlands glaciers a minimum of as much as warm air is melting them from above. Since ice loss from Greenlands ice sheet presently contributes more to the international rise of the oceans than any other single source, this finding has actually changed researchers understanding of the speed of sea level increase in the coming years.
These brand-new, special measurements have clarified the likely development of future ice loss in a place where glaciers are melting 6 or seven times much faster today than they were only 25 years back. If all of Greenlands ice sheet were to melt, global sea levels would increase by about 24 feet (7.4 meters).
