Studying ice caps/melt, ground water depletion etc

For scientific papers on AGW, record happenings in the Arctic and the Greenland, Himalayan and Antarctic icesheets. Also weatherstorms and higher than average rainfalls and other extreme weather events.

Studying ice caps/melt, ground water depletion etc

Postby HBS Guy » 20 Sep 2017, 17:23

A sentinel of Earth’s climate is going dark. After running for a decade beyond its planned life, the Gravity Recovery and Climate Experiment (GRACE) is nearly out of fuel and will soon make its final science run, NASA announced late yesterday. The tandem of satellites—called GRACE-1 and GRACE-2—measure minute shifts in Earth’s gravity to chart flows of mass across the planet, such as the unexpectedly rapid melt of polar ice sheets and the drawdown of underground water reservoirs called aquifers.

Scientists had hoped GRACE would operate until its successor, the $550 million GRACE Follow-on (GRACE-FO) mission, reached orbit. But troubles securing a ride to space have delayed GRACE-FO’s launch until early 2018. Meanwhile, the battery in GRACE-2 used to store solar power has been deteriorating rapidly, forcing the satellite to burn through fuel. Engineers turned off an accelerometer last year to keep it running, but the satellite’s data have continued to degrade.

On 4 September, scientists lost contact with GRACE-2 after another of its battery cells stopped operating. Four days of feverish work followed, with scientists steeling themselves for the mission’s end. But finally, engineers bypassed the satellite’s flight software, successfully rebooting it. NASA has now put GRACE-2 on standby until mid-October, when it will run until early November in full sun on its final planned science collection.

However small, a gap between the missions will make it more challenging to stitch their records together into a seamless whole, says Eric Rignot, a glaciologist at NASA’s Jet Propulsion Lab in Pasadena, California. There are alternative ways to calculate some of the measures GRACE provides, so stopgaps are possible. For example, changes in the mass of the ice sheets can be estimated by using other satellite data to compare discharges of peripheral ice to snowfall accumulations. But there is no comparable method to monitor changes in the mass of glaciers or ice caps, let alone the measures of Earth’s groundwater and soil moisture that hydrologists derive from the satellites. “It would be an impossible task to fill the gap,” Rignot says.[/unquote]

Eric Rignot made a video talking about the instability all ice sheets are now showing (Greenland, W and East Antarctica.)

A joint U.S.-German effort, GRACE has provided an unprecedented view of the planet’s water and ice since its launch in 2002. The experiment relies on measuring changes in the tug of gravity as the two satellites orbit the Earth. Flying 220 kilometers apart, the GRACE satellites constantly monitor their distance from each other with microwave pulses, down to microns. When the satellites approach a more massive feature, such as an ice sheet, the enhanced gravity of that region tugs a little bit more on the first satellite—briefly widening the distance between the pair—before the second satellite catches up. The changes in distance can be translated into mass.

This data revolutionized entire disciplines, such as hydrology, allowing scientists to document the loss of groundwater due to human exploitation. GRACE showed that the melting polar ice sheets are contributing more to sea level rise than the demise of mountain glaciers. Greenland, it found, is losing 280 gigatons of ice a year on average, while Antarctica is shedding 120 gigatons—rates that both seem to be accelerating. GRACE also inspired a similar mission, NASA’s Gravity Recovery and Interior Laboratory, which probed the moon’s interior.


http://www.sciencemag.org/news/2017/09/satellites-measuring-earth-s-melting-ice-sheets-go-dark
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Re: Studying ice caps/melt, ground water depletion etc

Postby HBS Guy » 13 Oct 2017, 06:40

On Greenland they believe Trumpy is insane to doubt AGW. Just insane!

The Arctic is warming twice as fast as the rest of the planet, as burning fossil fuels, industrialized farming and deforestation increase the amount of greenhouse gases in the atmosphere. Here on the world’s largest island, temperatures have climbed by 1.5 degrees Celsius, compared to about 0.7 degrees Celsius ― or 1.3 degrees Fahrenheit ― worldwide.


Reindeer no longer visit northern Greenland:
KANGERLUSSUAQ, Greenland ― Knud Lyberth walked slowly back on the lone paved road that cuts through the middle of this remote former U.S. military outpost, his rifle slung over his shoulder and his 17-year-old brother, Enos, by his side. On their trek last month, they didn’t spot a single reindeer after hours spent stalking the jagged hills of this windswept fjord, hiking miles through the pink heather and burnt-orange arctic brush.

This has become the new normal.


Melting ice.
The most dramatic episode came in 2012, when the ice barrier containing a glacial lake burst, flooding the silty river that runs through Kangerlussuaq (pronounced KONG-guh-SHLOO-shwock). The river rose several feet, destroying the small bridge that connects the main part of the town ― where the airport is located ― to the dirt roads that lead to a research station, a landfill and a lakeside restaurant.


Hunting and fishing changes.
Some people in Greenland stand to benefit as its towering ice walls retreat. The country, an autonomous region and former colony of the Kingdom of Denmark, has been furiously debating whether to mine the newly-reachable areas for rare earths metals and uranium. Extracting those resources threatens the pristine environment, but offers potential income streams that could provide jobs and help Greenland wean itself off the Danish subsidies it depends on to get by. Denmark has provided about $535 million in subsidies this year ― more than half of government revenues and 25 percent of Greenland’s gross domestic product.

In a country where fishing exports fuel 90 percent of the economy, warming waters are luring lucrative fish species north, including mackerel and Atlantic bluefin tuna, which locals call “pink gold.” Less ice also means a longer hunting season and easier access for Orca whales, whose meat, blubber and skin provide prized delicacies to Inuit hunters.

But traditional hunters in Greenland’s remote northern settlements are struggling, unable to safely drive their dog sleds out to islands on melting ice bridges. And there are scarier signs of the changing climate. In August, unprecedented wildfires burned in an area near Kangerlussuaq, wafting smoke over the airport, where Bibane Petersen, 26, works.


And some idiots are believing liars that we are in an ice age, active self-delusion.

http://www.huffingtonpost.com.au/entry/greenland-trump-climate_us_59dbf018e4b0b34afa5ba483
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