RollingThunder
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- Mar 22, 2010
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Here is some more relevant info on the melting of the Arctic ice cap.
Study reveals how Arctic Ocean drives ice melt
Morning Post Exchange
March 3, 2016
Fairbanks - Unprecedented ice melt in the Arctic Ocean is not caused by warming air alone, according to a recent study that emerged from a workshop at the University of Alaska Fairbanks.
Sea ice in the Arctic has continued to get thinner and smaller and to move faster during the past two decades.
Examining a collection of observational data obtained for more than two decades, a group of more than two dozen international researchers gathered at the March 2013 workshop to tackle the question of whether the increasing warmth of the Arctic Ocean itself is melting its own cover of ice.
The results were published in December in the Bulletin of the American Meteorological Society.
Researchers investigated how the effects of ocean currents, salinity, wind and ice interact with one another to accelerate sea ice melting. They showed that small changes in ways the ocean transports heat to the ice cover could have a substantial impact on future changes in Arctic ice cover.
“Sea ice loss has implications for governance, economics, security and global weather, so it is critical to understand how ocean, ice and air interact,” said Igor Polyakov of the UAF International Arctic Research Center, who was one of the lead authors of the study.
The Atlantic and Pacific Oceans are heating up and warmer currents are flowing into the Arctic Ocean. The heat from these currents would melt the Arctic sea ice instantly, Polyakov said, but so far it hasn’t happened because the warm currents don’t come into direct contact with the ice.
“The reason is these currents are saltier, therefore heavier, so they sink deeper into the ocean. Colder, fresher surface water partly shields the ice on the surface from warm water below,” he said.
Wind and faster-moving ice floes stir the ocean below, causing cold surface water and warm waters below to mix. As they are mixed, warmer water is brought to the surface and melts the ice cover from beneath it.
As this process continues, more sea ice melts.
The heat from the sun not only directly melts the sea ice but also heats up the water between ice floes, which is darker than ice and absorbs more heat. The heat from the sun also penetrates the thin areas of the ice, causing them to break from bigger, solid masses of ice. These smaller ice floes move freely.
Fresh water rushing from the large Siberian and North American rivers add more warm water to the ocean and accelerate ice melt, according to the paper.
The Arctic is warming faster than any other region on the planet.
“Sea ice melt in the Arctic is one of the most visible indicators of global climate change,” said Peter Winsor of the UAF Institute of Marine Science, who contributed to the study.
The study presents the most comprehensive summary so far of the current understanding of how heat reaches the ice base from the original sources, such as currents from different oceans and river discharge. The study gives key directions for creating more realistic future projections of the warmer and more dynamic “new Arctic.”
“Physical mechanisms within the Arctic Ocean impact biological, chemical, geological and physical processes and occur across sovereign state boundaries,” noted Polyakov. “So it is really important that we make multidisciplinary, multiagency and multinational efforts to reduce uncertainties in the projections of the future Arctic.”well here from one of your trusted sites: (2014)
Antarctic Sea Ice Reaches New Record Maximum
Excerpt:
"The upward trend in the Antarctic, however, is only about a third of the magnitude of the rapid loss of sea ice in the Arctic Ocean.
The new Antarctic sea ice record reflects the diversity and complexity of Earth’s environments, said NASA researchers. Claire Parkinson, a senior scientist at NASA’s Goddard Space Flight Center, has referred to changes in sea ice coverage as a microcosm of global climate change. Just as the temperatures in some regions of the planet are colder than average, even in our warming world, Antarctic sea ice has been increasing and bucking the overall trend of ice loss."
This is 2016.....and ol' JustCrazy posts an old article from 2014 (Oct. 7, 2014), citing info that is no longer correct, and spewing the usual deranged denier cult propaganda.
The minor increase in wintertime maximimum Antarctic sea ice has been one of the denier cult's big talking points....for duping scientifically ignorant retards. The thin fringe of sea ice a couple of meters thick (around a continent covered in miles thick ice sheets) had been increasing slightly in recent years at its Southern Hemisphere winter maximum extent.....
But not this year -
2015 Antarctic maximum sea ice extent breaks streak of record highs
NASA
October 19, 2015
By Maria-José Viñas,
The sea ice cover of the Southern Ocean reached its yearly maximum extent on Oct. 6. At 7.27 million square miles (18.83 million square kilometers), the new maximum extent falls roughly in the middle of the record of Antarctic maximum extents compiled during the 37 years of satellite measurements – this year’s maximum extent is both the 22nd lowest and the 16th highest. More remarkably, this year’s maximum is quite a bit smaller than the previous three years, which correspond to the three highest maximum extents in the satellite era, and is also the lowest since 2008.
.....but in its minimum months, sea ice extent has stayed fairly constant. Antarctic sea ice has been increasing slightly before this year because of increased precipitation caused by increased atmospheric water content that is itself caused by global warming. As the southern ocean continues to warm, scientists expect this Antarctic sea ice to continue to diminish. It has little bearing on global warming or global climate changes.
How does Arctic sea ice loss compare to Antarctic sea ice gain?
(excerpts)
Arctic sea ice loss is three times greater than Antarctic sea ice gain. The first point to clarify is that we are talking about floating sea ice, not to be confused with land ice. Land ice at both poles and in glaciers around the world is sliding into the ocean at an accelerating rate. This net loss of land ice is contributing to sea level rise.
Figure 1: Global sea ice extent since 1979. (Image source: Tamino. Data is from US National Snow and Ice Data Center.)
Figure 2: National Snow and Ice Data Center (NSIDC) Antarctic, Arctic, and global (sum of the two) sea ice extents with linear trends. The data is smoothed with a 12-month running average.
Sea ice grows and shrinks seasonally because polar latitudes have vastly more daylight hours in summer than in winter. When ice melts, it makes the surface less reflective and amplifies the warming (as is currently occurring in the Arctic), but this effect can only make a difference when the Sun is up. Thus the most important time of year for sea ice is its annual minimum which occurs at the end of the summer: September in the Arctic but February in the Antarctic. So how do the two compare?
Figure 3: Minimum sea ice extent since 1979 in the Arctic and Antarctic. (Image source: James Hansen. Data is from US National Snow and Ice Data Center.)
On the contrary, I totally debunked your idiotic ravings, JustCrazy.so you can't dispute my post
...because you are an ignorant, anti-science, denier cult RETARD....who is in deep denial about the fact that he just got his ass kicked by the scientific facts of the matter.I don't understand yours...