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If You Don't Believe In Global Warming-Have A Look At Greenland Now!


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2018 Jun 22, 3:08am   2,024 views  10 comments

by ohomen171   ➕follow (2)   💰tip   ignore  

#global warmingDAY IN REVIEW
NASA JPL latest news release
OMG, the Water's Warm! NASA Study Solves Glacier Puzzle
A new NASA study explains why the Tracy and Heilprin glaciers, which flow side by side into Inglefield Gulf in northwest Greenland, are melting at radically different rates.

Using ocean data from NASA's Oceans Melting Greenland (OMG) campaign, the study documents a plume of warm water flowing up Tracy's underwater face, and a much colder plume in front of Heilprin. Scientists have assumed plumes like these exist for glaciers all around Greenland, but this is the first time their effects have been measured.

The finding highlights the critical role of oceans in glacial ice loss and their importance for understanding future sea level rise. A paper on the research was published June 21 in the journal Oceanography.

Tracy and Heilprin were first observed by explorers in 1892 and have been measured sporadically ever since. Even though the adjoining glaciers experience the same weather and ocean conditions, Heilprin has retreated upstream less than 2.5 miles (4 kilometers) in 125 years, while Tracy has retreated more than 9.5 miles (15 kilometers). That means Tracy is losing ice almost four times faster than its next-door neighbor.

This is the kind of puzzle OMG was designed to explain. The five-year campaign is quantifying ice loss from all glaciers that drain the Greenland Ice Sheet with an airborne survey of ocean and ice conditions around the entire coastline, collecting data through 2020. OMG is making additional boat-based measurements in areas where the seafloor topography and depths are inadequately known.

About a decade ago, NASA's Operation IceBridge used ice-penetrating radar to document a major difference between the glaciers: Tracy is seated on bedrock at a depth of about 2,000 feet (610 meters) below the ocean surface, while Heilprin extends only 1,100 feet (350 meters) beneath the waves.

Scientists would expect this difference to affect the melt rates, because the top ocean layer around Greenland is colder than the deep water, which has traveled north from the midlatitudes in ocean currents. The warm water layer starts about 660 feet (200 meters) down from the surface, and the deeper the water, the warmer it is. Naturally, a deeper glacier would be exposed to more of this warm water than a shallower glacier would.

When OMG Principal Investigator Josh Willis of NASA's Jet Propulsion Laboratory in Pasadena, California, looked for more data to quantify the difference between Tracy and Heilprin, "I couldn't find any previous observations of ocean temperature and salinity in the fjord at all," he said. There was also no map of the seafloor in the gulf.

OMG sent a research boat into the Inglefield Gulf in the summer of 2016 to fill in the data gap. The boat's soundings of ocean temperature and salinity showed a river of meltwater draining out from under Tracy. Because freshwater is more buoyant than the surrounding seawater, as soon as the water escapes from under the glacier, it swirls upward along the glacier's icy face. The turbulent flow pulls in surrounding subsurface water, which is warm for a polar ocean at about 33 degrees Fahrenheit (0.5 degree Celsius). As it gains volume, the plume spreads like smoke rising from a smokestack.

"Most of the melting happens as the water rises up Tracy's face," Willis said. "It eats away at a huge chunk of the glacier."

Heilprin also has a plume, but its shallower depth limits the plume's damage in two ways: the plume has a shorter distance to rise and gathers less seawater; and the shallow seawater it pulls in has a temperature of only about 31 degrees Fahrenheit (minus 0.5 degree Celsius). As a result, even though Heilprin is a bigger glacier and more water drains from underneath it than from Tracy, its plume is smaller and colder.

The study produced another surprise by first mapping a ridge, called a sill, only about 820 feet (250 meters) below the ocean surface in front of Tracy, and then proving that this sill did not keep warm water from the ocean depths away from the glacier. "In fact, quite a lot of warm water comes in from offshore, mixes with the shallower layers and comes over the sill," Willis said. Tracy's destructive plume is evidence of that.

Comments 1 - 10 of 10        Search these comments

2   HeadSet   2018 Jun 22, 6:41am  

So Greenland will become more ice-free and contain more arable land? Just like in the 1500's before the cooling came and froze the Viking settlers out? How is this bad? Is it bad because it is a change?
3   RWSGFY   2018 Jun 22, 7:27am  

How's land prices there?
4   Shaman   2018 Jun 22, 8:22am  

Has anyone thought that perhaps geologically active areas could explain the difference? Or slope gradient and glacier base? If one glacier moves faster than another, and further has rock to grind against rather than sea water, it will generate much more friction which translates directly into heat. Since heat is needed to melt water from ice, the glacier with the most heat generation will melt the fastest. Their explanation of “plumes” is retarded, like this “warm” water would somehow stay warm even as it gives up its heat to make the glacier melt.
5   clambo   2018 Jun 22, 8:53am  

Maybe someday it will be how it was when the Vikings inhabited it. They had to abandon it because of the cold.
6   Bd6r   2018 Jun 22, 9:40am  

Hassan_Rouhani says
How's land prices there?


For a wonderful vacation house please see http://www.ejendomskontoret.gl/

I believe you can buy house/apartment, but all land is communally owned - might be a holdover from some kind of Danish medieval laws.
7   Onvacation   2018 Jun 22, 9:49am  

So how much has the sea rose and when is Manhattan going under?
8   Malcolm   2018 Jun 22, 10:03am  

More alarmism from insignificant natural variations with no impact on anything. Note the "radically" for more punch.
9   Tenpoundbass   2018 Jun 22, 10:15am  

Water goes on top, then the water on the bottom goes down the hoooooooole


If the sea level was rising, don't you think all of the rivers emptying into the Ocean would have swamped Mount Everest by now over the billions of years?

Just where do the Sea Level Risers think river water and storm run off is going? Just where do they think the billions and trillions of gallons of water in the world's aquifers are coming from?
10   Ceffer   2018 Jun 22, 11:15am  

The only water that's rising is the water in the brains of the alarmists.

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