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Key data for NASA's ice monitoring satellites shutting down into trouble



The highest mountain in Greenland, Mt. Gunnbjørn, as seen from an Operation IceBridge flight.
Photo: NASA / Joe MacGregor (Flickr)

Last month, NASA researchers cheerfully shared the early results of their recently launched ICESat-2 ice monitoring satellite in the world's largest annual Earth scientist convention. Many of these researchers are thrilled this month as an important airborne campaign is needed to calibrate the satellite's increasing delays due to the closure of the US government.

Science Magazine reported last week that the spring campaign for NASA's Operation IceBridge – a series of airborne flights over the Arctic and Antarctic that space agency has been carrying out since 2009, would probably be due to President Trump's fictional crisis on the southern border delay the US. Now, several scientists involved in IceBridge and ICESat-2 have told Earther that the campaign, which was originally scheduled to start on March 4 and run for eight weeks, threatens delays of up to a month and may halve the field season.

Sol delays would dramatically reduce the amount of data that researchers could collect this spring – data needed to maintain uninterrupted record keeping and data validation during the ICESat-2 Space Agency mission $ 1 billion.

"A Big Part of Our Spring The campaign plan should be [ground-truthing]," said John Sunday, mission scientist from Operation IceBridge, to Earther. (Ground truthing is the process of comparing satellite measurements to earth measurements that did the same thing.) "Until then, the taxpayer will not get nearly as much return on his $ 1 billion spacecraft investment as he should be.

The IceBridge mission was developed to bridge the data gap between ICESat, a satellite laser altimeter that measures the height of icy surfaces on Earth from 2003 to 2009, and ICESat-2, which now collects similar data for higher resolution , These missions provide NASA with crucial information on how ice shelves and glaciers melt and move in a warming world, helping to locate subglacial lakes and other icy features. IceBridge aircraft are equipped with a handful of laser altimeters to keep track of the ICESat recordings, as well as radar instruments to peer through the ice and other mapping tools.

NASA normally spends two months of spring flying across the Arctic, followed by a month-long autumn campaign in the Antarctic. With the launch of ICESat-2, this year's Spring IceBridge campaign – the penultimate for the Arctic with a shorter campaign planned for the summer – is playing a crucial role. The team plans to fly many of the same routes as ICESat-2, allowing researchers to verify and ensure that the satellite achieves accurate measurements in a variety of icy areas.

"At the same time, ICESat and IceBridge measurements give us a clear understanding of how these two sets of data relate to each other," said Ben Smith, a University of Washington glaciologist who has worked in both the IceBridge and the United States ICESat 2 science teams.

According to Sunday, The P -3B Orion aircraft that NASA is using for this spring was on a different mission last fall and needs to be serviced before it is ready to fly again While NASA received a waiver last week to begin maintenance before the P-3B stops working, Sonntag said the agency had lost "most of the month" and it would take time to catch up The integration of the scientific instruments required for IceBridge, including the laser altimeter, has come to a complete standstill as a result of the shutdown.

To what extent? These delays affect the data that NASA captures this spring is still unclear. Sunday said that after the end of the Arctic campaign in the spring, the plane is needed for another mission, so it is unlikely (though not impossible) that IceBridge can make up for the lost time. Eric Rignot, Glaciologist at NASA's Jet Propulsion Laboratory and senior IceBridge ice-bridge ice team, told Earther that the campaign was "cut by almost half" In the autumn, important measures were taken in the Antarctic "Rignot said in an email to Earther, referring to the fall IceBridge campaign. "This shutdown is detrimental and the damage becomes more serious if it lengthens. Exponentially. "

" There will be a significant loss of opportunity, "said Ron Kwok, a researcher at NASA's Jet Propulsion Laboratory, who works on both the IceBridge and ICESat-2 science teams.

Kwok explained that if ICESat-2 works well (and the satellite has performed well so far), a limited IceBridge dataset for calibration should not be a big deal. "But we're still working on data quality at this point," he said. "If we did not have a reference dataset that we could fall back on when we needed it, that would be a significant problem."

Smith was unwilling to reject it as a minor inconvenience.

"I think we can handle everything, but at this point it's impossible to say," he said. "It's an additional uncertainty where ICESat-2 hoped we would reduce uncertainty . "


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