West Antarctic Ice Melt; Water or Fire?
Poor Global Warming just can't catch a break. Planetary temperatures aren't cooperating, nor is the rate of sea level rise, and now even West Antarctica seems to be gouging James Hansen in the eye.
Researchers at Washington University in St. Louis have discovered a chain of active volcanoes under the West Antarctic ice sheet.
This is interesting because West Antarctica is the region that Global Warming hysterics (the Gang Green) point to as "proof" that Global Warming is happening to the southernmost polar region. Now we see there may be another reason for ice loss in WAIS.
From the press release:
Will the new volcano erupt?
"Definitely,” Lough said. "In fact, because the radar shows a mountain beneath the ice, I think it has erupted in the past, before the rumblings we recorded.”
Will the eruptions punch through a kilometer or more of ice above it?
The scientists calculated that an enormous eruption, one that released 1,000 times more energy than the typical eruption, would be necessary to breach the ice above the volcano.
MacAyeal Ice Stream.
On the other hand, a subglacial eruption and the accompanying heat flow will melt a lot of ice. "The volcano will create millions of gallons of water beneath the ice — many lakes full,” Wiens said.
This water will rush beneath the ice toward the sea and feed into the hydrological catchment of the MacAyeal Ice Stream, one of several major ice streams draining ice from Marie Byrd Land into the Ross Ice Shelf.
By lubricating the bedrock, it will speed the flow of the overlying ice, perhaps increasing the rate of ice-mass loss in West Antarctica.
"We weren’t expecting to find anything like this,” Wiens said.
Which means that we will have precisely the situation we have witnessed in WAIS; an acceleration in ice shelf collapse there.
In other words, carbon dioxide has nothing to do with it.
This contradicts claims by NASA, which blames West Antarctic Ice Sheet loss on warm ocean currents.
From the June 2013 press release:
"The study uses reconstructions of ice accumulation, satellite and aircraft readings of ice thickness, and changes in elevation and ice velocity to determine how fast ice shelves melt and compare the mass lost with the amount released by the calving, or splitting, of icebergs.
"The traditional view on Antarctic mass loss is it is almost entirely controlled by iceberg calving," said Eric Rignot of NASA's Jet Propulsion Laboratory in Pasadena, Calif., and the University of California, Irvine. Rignot is lead author of the study to be published in the June 14 issue of the journal Science. "Our study shows melting from below by the ocean waters is larger, and this should change our perspective on the evolution of the ice sheet in a warming climate."
Ice shelves grow through a combination of land ice flowing to the sea and snow accumulating on their surface. To determine how much ice and snowfall enters a specific ice shelf and how much makes it to an iceberg, where it may split off, the research team used a regional climate model for snow accumulation and combined the results with ice velocity data from satellites, ice shelf thickness measurements from NASA's Operation IceBridge - an continuing aerial survey of Earth's poles - and a new map of Antarctica's bedrock.
Using this information, Rignot and colleagues were able to deduce whether the ice shelf was losing mass through basal melting or gaining it through the basal freezing of seawater.
In some places, basal melt exceeds iceberg calving. In other places, the opposite is true. But in total, Antarctic ice shelves lost 2,921 trillion pounds (1,325 trillion kilograms) of ice per year in 2003-2008 through basal melt, while iceberg formation accounted for 2,400 trillion pounds (1,089 trillion kilograms) of mass loss each year.
Basal melt can have a greater impact on ocean circulation than glacier calving. Icebergs slowly release melt water as they drift away from the continent. But strong melting near deep grounding lines, where glaciers lose their grip on the seafloor and start floating as ice shelves, discharges large quantities of fresher, lighter water near the Antarctic coast line. This lower-density water does not mix and sink as readily as colder, saltier water, and may be changing the rate of bottom water renewal."
At the same time, Antarctic sea ice extent is at an all time high.
This makes no sense if you assume carbon dioxide is warming the atmosphere and thus leading to ice melt. In fact, it makes no sense if you assume the missing heat, the warming that is supposedly happening because of Global Warming but cannot be found, is going into the oceans, either. Sea ice forms because it is cold, plain and simple, and it is not moved out by ocean currents.
And a review of the Icesat satellite data from the time period of 1992 to 2008 showed a net gain in ice mass in Antarctica as well. http://wattsupwiththat.com/2012/09/10/icesat-data-shows-mass-gains-...
Now we know what caused this basal melt - not warm ocean currents but volcanoes underneath the ice.
It should be further pointed out that the number of small Antarctic icebergs have not risen; Nasa is correct in not attributing iceberg calving on the increase in sea ice. http://archimer.ifremer.fr/doc/00083/19444/17050.pdf (see figures 5 and 6.) Antarctic icebergs - unlike their Arctic cousins that are spawned by glaciers - form when a section of ice breaks off an ice shelf. If the WAIC were disintegrating we would should see more icebergs. We do not, which lead NASA to make the claim that the ice was melting from beneath, a result of deep, warm ocean currents. But now we know that ice is melting not from warm water but from geothermal activity.
The case for Global Warming grows increasingly thin.
Sea levels actually dropped in 2010 http://notrickszone.com/2011/08/31/der-spiegel-global-warming-now-c..., and their rise has slowed significantly in the last few years. http://wattsupwiththat.com/2013/05/28/obama-was-rightthe-rise-of-th... What does that mean?
It means more ice at the polls, or more water vapor in the atmosphere. If water vapor levels have risen we should see an increase in precipitation worldwide. There is no evidence of that.
Unless the extra water is hiding in the deep oceans along with that missing heat.
It's getting crowded down there.
Read more from Tim and friends at The Aviary www.tbirdnow.mee.nu