Shutdown imperils NASA’s decadelong ice-measuring campaign | Science

6 bulan ago kesimpulan 0
Bringing you the latest Science news from the world.

What is happening in our world? Who is discovering what? What is going on now? These are questions that will be answered. Enjoy.

Shutdown imperils NASA’s decadelong ice-measuring campaign | Science

Delayed maintenance work means NASA’s P-3 Orion will miss at least half of its IceBridge campaign to measure Arctic sea ice.

Christy Hansen/NASA (CC BY)

The spreading effects of the partial U.S. government shutdown have reached Earth’s melting poles. IceBridge, a decadelong NASA aerial campaign meant to secure a seamless record of ice loss, has had to sacrifice at least half of what was supposed to be its final spring deployment, its scientists say. The shortened mission threatens a crucial plan to collect overlapping data with a new ice-monitoring satellite called the Ice, Cloud, and Land Elevation Satellite (ICESat)-2.

The nearly monthlong spending impasse between Congress and President Donald Trump, “throws a giant wrench into that long-developed plan,” says John Sonntag, an IceBridge mission scientist at Goddard Space Flight Center in Greenbelt, Maryland.

NASA, among the many research agencies mostly closed by the shutdown, launched IceBridge in 2009 after the failure of ICESat-1, the agency’s first laser-based ice-monitoring satellite. To fill the gap until ICESat-2 was launched, the agency funded annual aircraft flights over the Arctic and Antarctica. IceBridge scientists sought to match the satellite data by flying similar paths over glaciers and sea ice, using the reflected light of a laser altimeter to measure ice and snow height.

This year’s 8-week Arctic campaign was set to start 4 March from Thule Air Base in Greenland. But the shutdown has delayed maintenance and outfitting of the aircraft NASA uses—a low-flying P-3 Orion—forcing a later start date.

Researchers are crestfallen. The measurements are among IceBridge’s most important because they will be simultaneous with those made by ICESat-2, which launched in September 2018. That will help ensure the satellite’s accuracy and calibrate its results with past records. “We expected to be in an ideal position this spring,” Sonntag says. (He can talk to the media, he noted, because he is a NASA contractor who is still getting paid. Many NASA employees on his team are furloughed.)

IceBridge could still lose more time. The flights must take place before the melt season, and the P-3 is already scheduled to move to the Philippines immediately after its polar flights for a monsoon-monitoring experiment. As a result, the delay “could get worse if the shutdown goes on,” says Eric Rignot, a glaciologist at the University of California, Irvine, and a leader of the IceBridge science team.

One bit of good news is that NASA recently allowed maintenance work to begin on the P-3, which is based at NASA’s Wallops Flight Facility in Virginia. Even if that work is done, the science team does not have permission to enter the facility to mount its instruments, including a laser meant to match ICESat-2’s remarkably precise altimeter. In the meantime, NASA’s closure means work on understanding the new ICESat-2 data has slowed to a crawl, says Ben Smith, a glaciologist at the University of Washington in Seattle. “One main thing we’re missing right now is the people at NASA who have the big picture, who get everyone to work together.”

The IceBridge and ICESat-2 data sets will be merged even if the spring campaign is canceled, which would be “inexcusable,” adds Beata Csatho, a remote-sensing glaciologist at the University at Buffalo, part of the State University of New York system. But Smith says a cancellation could make it harder to fix any systematic errors that crop up in the satellite data. “If you’re planning for the worst,” he says, “you definitely want to get this set of measurements.”

It’s not the first time IceBridge has faced a shutdown. In 2013, a 16-day budget impasse cut what could have been a 6-week campaign to 9 days. That has left uncertainty about ice loss that continues to disappoint Sonntag to this day. “I have never been so angry and frustrated,” he recalls. But with the current shutdown, he’s getting close.

Source link

Iklan