Editorial Note: You might of heard all the caterwauling over recent scientific evidence of our south and north poles are melting due to global warming. I suspect these reports are largely used by those who want to impose a carbon tax. In essence tax you for the air you breathe! But one can't ignore that our polar caps are melting, that's based on NASA's studies. Despite any motives that others may have regarding theses reports I am sharing.
Here are some reports from NASA:
New Light on the Future of a Key Antarctic Glacier
Study Shows Thwaites Glacier's Ice Loss May Not Progress as Quickly as Thought
The melt rate of West Antarctica's Thwaites Glacier is an important concern, because this glacier alone is currently responsible for about 1 percent of global sea level rise. A new NASA study finds that Thwaites' ice loss will continue, but not quite as rapidly as previous studies have estimated.
The new study, published in the journal Geophysical Research Letters, finds that numerical models used in previous studies have overestimated how rapidly ocean water is able to melt the glacier from below, leading them to overestimate the glacier's total ice loss over the next 50 years by about 7 percent.
Thwaites Glacier covers an area nearly as large as the state of Washington (70,000 square miles, or 182,000 square kilometers). Satellite measurements show that its rate of ice loss has doubled since the 1990s. The glacier has the potential to add several inches to global sea levels.
The new study is led by Helene Seroussi, a scientist at NASA's Jet Propulsion Laboratory in Pasadena, California. It is the first to combine two computer models, one of the Antarctic ice sheet and one of the Southern Ocean, in such a way that the models interact and evolve together throughout an experiment -- creating what scientists call a coupled model.
Previous modeling studies of the glacier used only an ice sheet model, with the effects of the ocean specified beforehand and unchanging.
Seroussi and colleagues at JPL and the University of California at Irvine (UCI) used an ocean model developed at the Massachusetts Institute of Technology in Cambridge with an ice sheet model developed at JPL and UCI. They used data from NASA's Operation Icebridge and other airborne and satellite observations, both to set up the numerical model simulations and to check how well the models reproduced observed changes.
Glaciers have beds just as rivers do, and most glacier beds slope downhill in the same direction the glacier is flowing, as a riverbed does. Thwaites Glacier's bed does the opposite: it slopes uphill in the direction of flow. The bedrock under the glacier's ocean front is higher than bedrock farther inland, which has been pushed down over the millennia by its heavy burden of ice.
Thwaites has lost so much ice that it floats where it used to be attached to bedrock. That has opened a passageway underneath the glacier where ocean water can seep in.
In this part of Antarctica, the warm, salty, deep ocean current that circles the continent comes near land, and warm water can flow onto the continental shelf. This warm seawater now seeps beneath Thwaites Glacier, melting it from below.
As the glacier continues to melt, grow thinner and float off bedrock farther and farther inland, new cavities will continue to open up. Because the bedrock slopes downhill, there's no natural barrier to stop this process. Earlier modeling studies assumed that water in the new cavities would continue to melt the glacial underside at the same rate that it's melting now.
Seroussi's coupled model found that water circulation is more restricted in these narrow spaces, and as a result, the water will melt the ice more slowly than previously thought.
Seroussi noted that critical factors affecting Thwaites, such as how nearby ocean temperatures will change, are still unknown and represented by different scenarios in different studies. However, "Our results shift the estimates for sea level rise to smaller numbers regardless of the scenario," she said.---Written by Carol Rasmussen NASA's Earth Science News Team
Source: NASA: https://www.nasa.gov/feature/jpl/new-light-on-the-future-of-a-key-antarctic-glacier
Other stories from NASA
NASA Discovers a New Mode of Ice Loss in Greenland
A new NASA study finds that during Greenland's hottest summers on record, 2010 and 2012, the ice in Rink Glacier on the island's west coast didn't just melt faster than usual, it slid through the glacier's interior in a gigantic wave, like a warmed freezer pop sliding out of its plastic casing. The wave persisted for four months, with ice from upstream continuing to move down to replace the missing mass for at least four more months.
https://www.nasa.gov/feature/jpl/nasa-discovers-a-new-mode-of-ice-loss-in-greenland
Alaska Tundra Source of Early-Winter Carbon Emissions
Warmer temperatures and thawing soils may be driving an increase in emissions of carbon dioxide from Alaskan tundra to the atmosphere, particularly during the early winter, according to a new study supported by NASA and the National Oceanic and Atmospheric Administration (NOAA). More carbon dioxide released to the atmosphere will accelerate climate warming, which, in turn, could lead to the release of even more carbon dioxide from these soils.
A new paper led by Roisin Commane, an atmospheric researcher at Harvard University in Cambridge, Massachusetts, finds the amount of carbon dioxide emitted from northern tundra areas between October and December each year has increased 70 percent since 1975. Commane and colleagues analyzed three years of aircraft observations from NASA’s Carbon in Arctic Reservoirs Vulnerability Experiment (CARVE) airborne mission to estimate the spatial and seasonal distribution of Alaska’s carbon dioxide emissions. They also studied NOAA’s 41-year record of carbon dioxide measured from ground towers in Barrow (the name recently changed back to Utqiagvik), Alaska. The aircraft data provided unprecedented spatial information, while the ground data provided long-term measurements not available anywhere else in the Arctic. Results of the study are published today in the Proceedings of the National Academy of Sciences.
https://www.nasa.gov/feature/jpl/alaska-tundra-source-of-early-winter-carbon-emissions
Historical footnotes on who discovered both poles
South Pole: Amundsen's South Pole expedition
The first expedition to reach the geographic South Pole was led by the Norwegian explorer Roald Amundsen. He and four others arrived at the pole on 14 December 1911, five weeks ahead of a British party led by Robert Falcon Scott as part of the Terra Nova Expedition. Amundsen and his team returned safely to their base, and later learned that Scott and his four companions had died on their return journey.
Amundsen's initial plans had focused on the Arctic and the conquest of the North Pole by means of an extended drift in an icebound ship. He obtained the use of Fridtjof Nansen's polar exploration ship Fram, and undertook extensive fundraising. Preparations for this expedition were disrupted when, in 1909, the rival American explorers Frederick Cook and Robert E. Peary each claimed to have reached the North Pole. Amundsen then changed his plan and began to prepare for a conquest of the South Pole; uncertain of the extent to which the public and his backers would support him, he kept this revised objective secret. When he set out in June 1910, he led even his crew to believe they were embarking on an Arctic drift, and revealed their true Antarctic destination only when Fram was leaving their last port of call, Madeira.---wikipedia
https://en.wikipedia.org/wiki/Amundsen%27s_South_Pole_expedition
North Pole: Robert Peary
Rear Admiral Robert Edwin Peary Sr. (May 6, 1856 – February 20, 1920) was an American explorer and United States Navy officer who made several expeditions to the Arctic in the late 19th and early 20th centuries. He is best known for claiming to have reached the geographic North Pole with his expedition on April 6, 1909.
Peary was born in Cresson, Pennsylvania, but raised in Portland, Maine, following his father's death at a young age. He attended Bowdoin College, then joined the National Geodetic Survey as a draftsman. Peary enlisted in the navy in 1881, as a civil engineer. In 1885, he was made chief of surveying for the Nicaragua Canal (which was never built).
In 1886, Peary visited the Arctic for the first time, making an unsuccessful attempt to cross Greenland by dogsled which was thwarted by a lack of supplies. He returned in 1891 much better prepared, and by reaching Independence Fjord (in what is now known as Peary Land) conclusively proved that Greenland was an island. Peary was one of the first Arctic explorers to study Inuit survival techniques, which he used to his great benefit.
On his 1898–1902 expedition, Peary set a new "Farthest North" record by reaching Greenland's northernmost point, Cape Morris Jesup. He also reached the northernmost point of the Western Hemisphere, at the top of Canada's Ellesmere Island. Peary made two further expeditions to the Arctic, in 1905–06 and in 1908–09. During the latter, he claimed to have reached the North Pole. Peary received a number of awards from geographical societies during his lifetime, and in 1911 received the Thanks of Congress and was promoted to rear admiral. He served two terms as president of The Explorers Club, and retired to Eagle Island.---wikipedia
https://en.wikipedia.org/wiki/Robert_Peary
Frederick Cook
Frederick Albert Cook (June 10, 1865 – August 5, 1940) was an American explorer, physician, and ethnographer, noted for his claim of having reached the North Pole on April 21, 1908. This was a year before April 6, 1909, the date claimed by the American explorer Robert Peary, and the accounts were disputed for several years. His expedition did discover Meighen Island, the only discovery of an island in the American Arctic by a United States expedition.
After reviewing Cook's limited records, a commission of the University of Copenhagen ruled in December 1909 that he had not proven that he reached the pole. In 1911 Cook published a memoir of his expedition, continuing to assert their success. His 1906 account of having reached the summit of Denali has also been discredited.
Cook claimed to have achieved the first summit of Denali (also known as Mt. McKinley) in September 1906, reaching the top with one other member of his expedition. Other members of the team (e. g., Belmore Browne), whom he had left lower on the mountain, expressed private doubts about this immediately. Cook's claims were not publicly challenged until the 1909 dispute with Peary over who had first reached the North Pole. Peary's supporters then publicly alleged that Cook's claim of ascent of Denali was fraudulent.----wikipedia
https://en.wikipedia.org/wiki/Frederick_Cook
UN NEWS CENTER: Record high temperatures grip much of the globe, more hot weather to come – UN agency
20 June 2017 – Extremely high May and June temperatures have broken records in parts of Europe, the Middle East, North Africa and the United States, the United Nations weather agency reported today, warning of more heatwaves to come.
http://www.un.org/apps/news/story.asp?NewsID=57024
For more news headlines see page 2
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