GLACIERS and POLAR ICE CAPS

More than 90% of the 33 million cubic kilometers of glacier ice in the world is locked up in the gigantic Greenland and Antarctic ice sheets. Researchers have found they can obtain a measure of average global temperatures by using satellites to monitor heat-sensitive objects on the ground. Of these objects, glaciers are among the most reliable indicators of climate change. Despite typical glaciers’ massive sizes, monitoring them is not always an easy task. Only specific types of small glaciers are good measures of climate change. Some glaciers are too large to measure accurately, and others are simply too unpredictable. Once scientists find a suitable glacier, they must take satellite images of the ice for a minimum of five years and compare the results.          

Dec. 13 2011: Retreat of Arctic sea ice release fountains of methane bubbling to surface. Dramatic and unprecedented plumes of have been seen bubbling to the surface of the Arctic Ocean by scientists undertaking an extensive survey of the region. The scale and volume of the methane release has astonished the head of the Russian research team who has been surveying the seabed of the East Siberian Arctic Shelf off northern Russia for nearly 20 years. Scientists estimate that there are hundreds of millions of tonnes of methane gas locked away beneath the Arctic permafrost, which extends from the mainland into the seabed of the relatively shallow sea of the East Siberian Arctic Shelf. One of the greatest fears is that with the disappearance of the Arctic sea-ice in summer, and rapidly rising temperatures across the entire region, which are already melting the Siberian permafrost, the trapped methane could be suddenly released into the atmosphere leading to rapid and severe climate change. link

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           Below:

• Antarctica  / Penguins
• Glaciers
• Arctic Ocean / Polar Bears                        

Antarctica accounts for 90% of the world's ice. The West coast of the Peninsula is warming at a rate 2 or 3 times faster than the global average. This has received a great deal of publicity in recent years and of course is where the Larsen B ice shelf is situated. The average annual temperature of this region has increased about 2.5C in the last 50 years. However, data on temperatures in Antarctica only really go back about 50 years, anything beyond that is surmised from ice cores or other sources and so we don't really know how the temperatures vary over even the medium term in Antarctica. The Antarctic Peninsula also represents only about 4% of the whole continent, the other 96% appears to have had a stable temperature over the last 40 years to the extent where the most remarkable aspect is the stability compared to other parts of the world.  link 

June  2011: Warmer water melting Antarctic glacier from below. Stronger ocean currents beneath West Antarctica's Pine Island Glacier Ice Shelf are eroding the ice from below, speeding the melting of the glacier as a whole, according to a new study in Nature Geoscience. A growing cavity beneath the ice shelf has allowed more warm water to melt the ice, the researchers say, a process that feeds back into the ongoing rise in global sea levels. The glacier is currently sliding into the sea at a clip of 4 kilometers a year, while its ice shelf is melting at about 80 cubic kilometers a year, 50% faster than it was in the early 1990s. link

May 2011: Arctic - an irreversible climate "tipping point" could occur within the next 20 years as a result of the release of huge quantities of organic carbon locked away as frozen plant matter in the vast permafrost region of the Arctic, scientists have found. Billions of tons of frozen leaves and roots that have lain undisturbed for thousands of years in the permanently frozen ground of the northern hemisphere are thawing out, with potentially catastrophic implications for climate change, the researchers said. A study into the speed at which the permafrost is melting suggests that the tipping point will occur between 2020 and 2030 and will mark the point at which the Arctic turns from being a net "sink" for carbon dioxide into an overall source that will accelerate global warming. The study is the first global investigation of what will happen in a warmer world to the huge amounts of frozen plant matter that has remained undegraded in the soil since it was incorporated into the permafrost about 30,000 years ago. It also found that by 2200 about two-thirds of the Earth's permafrost will have melted, releasing an estimated 190 billion tons of carbon dioxide and methane into the air, about half of all the fossil fuel emissions of greenhouse gases since the start of the industrial revolution.  link

January 2010: Major Antarctic glacier is 'past its tipping point' -  and is irreversibly on track to lose 50% of its ice in as little as 100 years, significantly raising global sea levels. link

December 2009: Warming waters and ozone hole repair leads to melting. The hole in the Earth's ozone layer has shielded Antarctica from the worst effects of global warming until now, according to the most comprehensive review to date of the state of the Antarctic climate. But scientists warned that as the hole closes up in the next few decades, temperatures on the continent could rise by around 3C on average, with melting ice contributing to a global sea-level increases of up to 1.4m. 
The heat in the ocean is getting underneath the floating ice shelves, these floating fringes of the ice sheet that are hundreds of metres thick. That warm water is melting the underside of the ice shelf, and thinning the ice shelf at the fringes leads to glaciers moving more quickly. The retreat of ice from Antarctica has contributed around 10% to global sea-level rise in recent decades. The danger is that this warmer water will get under these ice shelves and cause the ice streams to get faster and feed ice out into the ocean. link  (pictured: Upwelling seawater along parts of Pine Island Glacier Ice Shelf has carved out caves in the ice.) 

November 2009: World's largest ice sheet melting faster than expected. The world's largest ice sheet has started to melt along its coastal fringes, raising fears that global sea levels will rise faster than scientists expected. The East Antarctic ice sheet, which makes up 75% of the continent's 14,000 sq km, is losing around 57 billion tonnes of ice a year into surrounding waters, according to a satellite survey of the region. Data from the whole of Antarctica show the region is now losing around 190bn tonnes of ice a year. "If the current trend continues or gets worse, Antarctica could become the largest contributor to sea level rises in the world. It could start to lose more ice than Greenland within a few years. link

August 2009: One of the largest glaciers in Antarctica is thinning four times faster than it was 10 years ago, according to research seen by the BBC. A study of satellite measurements of Pine Island glacier in west Antarctica reveals the surface of the ice is now dropping at a rate of up to 16m a year. Since 1994, the glacier has lowered by as much as 90 meters, which has serious implications for sea-level rise. Calculations based on the rate of melting 15 years ago had suggested the glacier would last for 600 years. But the new data points to a lifespan for the vast ice stream of only another 100 years. link

March 2011: Research shows ice loss from Antarctica and Greenland has accelerated over the last 20 years. By 2006, the Greenland and Antarctic sheets were losing a combined mass of 475 billion tonnes of ice per year. If these increases persist, water from the two polar ice sheets could have added 15.9 inches to the average global sea level by 2050.   link

New evidence of warming in Antarctica. Headlines such as this (New York Times) appear frequently. This one reports on West Antarctica, where the base of some large ice sheets lies below sea level. Studies found that from 1957 through 2006, temperatures across Antarctica rose an average of 0.2 degrees Fahrenheit per decade, though temperatures in this area are still well below freezing and the warming will not have an immediate effect on sea level. In East Antarctica, where temperatures had been thought to be falling, the researchers found a slight warming over the 50-year period. With some uncertainty, East Antarctica may have indeed been cooling, but the rise in temperatures in the west more than offset the cooling. The average temperature for Antarctica is about minus 58 degrees. While some reports had suggested cooling was taking place, Michael Oppenheimer, a professor of geosciences at Princeton, who was not involved in the research said the situation is complex, resulting from a combination of man-made factors and natural variability - “But the idea of a long-term cooling is pretty clearly debunked.” he said.   link

Decline of penguins in Antarctica linked with climate change Over the past 50 years, the population of Antarctic emperor penguins has declined by 50%. Using the longest series of data available, researchers have shown that an abnormally long warm spell in the Southern Ocean during the late 1970s contributed to a decline in the population of emperor penguins at Terre Adelie, Antarctica. "We knew since the 1980s that emperor penguins had declined, but it is only today, because of the improvements of our knowledge in the climate-ocean processes, that we have been able to understand why they have decreased," said Henri Weimerskirch of the French National Center for Scientific Research in France.  Warmer air and sea surface temperatures in the Antarctic reduce the amount of ice in the sea. This, in turn, leads to smaller populations of krill, a shrimp-like crustacean that is a staple of the emperor penguin's diet. With less food to eat, emperor penguins die. Despite the findings that show a negative effect of global warming on emperor penguin populations, Weimerskirch cautions against making generalizations about the impacts of climate change on wildlife. For example, a reduction in the amount of sea ice is favorable to Adelie penguins, he said. On the other hand, elephant seals and some albatross species were also negatively affected by the prolonged warming period in the 1970s . link                More about Antarctic penguins - link

April 2011: Glaciers melting at fastest rate in 350 years, study finds. Scientists behind the discovery claim their findings show that the rate of melting at the start of the 20th century was much slower than previously calculated, but that over the past 30 years it has been significantly faster than suspected. link
January 2010: Glaciers across the globe are continuing to melt so fast that many will disappear by the middle of this century according to the WGMS (World Glacier Monitoring Service). The most vulnerable glaciers were those in lower mountain ranges like the Alps and the Pyrenees in Europe, in Africa, parts of the Andes in South and Central America, and the Rockies in North America. If you take a medium scenario about 70% of the Alps will be gone by 2050, and mountain ranges like the Pyrenees may be completely ice-free. link

         Snapshots of some glacier activity around the world:

Peru:  At left, Pucaranracocha glacier taken in 1932. At right Pucaranracocha glacier taken in 2009.  Source

Greenland:  Greenland is the front line in humanity's battle against climate change.     More and more of Greenland, whose frozen expanses are a living remnant of the last ice age, disappears each year, with as much as 150 billion metric tons of glacier vanishing annually, according to one estimate. If all the ice on Greenland were to melt tomorrow, global sea levels would rise more than 20 ft. - enough to swamp many coastal cities. link  Scott Luthcke,a scientist at NASA's Goddard Space Flight Center in Maryland, weighs Greenland, every 10 days. And the island has been losing weight, an average of 183 gigatons (or 200 cubic kilometers) in ice annually during the past six years. link

March  2010: Greenland's tipping point closer than previously thought. A new study has lowered the carbon pollution threshold or “tipping point” for collapse of the Greenland ice sheet to 400 to 560 ppm. (Currently at 390 ppm and rising at 2 ppm per year) - total collapse would take a while). link
February 2010: Greenland's glaciers disappearing from the bottom up. Water warmed by climate change is taking giant bites out of the underbellies of Greenland's glaciers. As much as 75% of the ice lost by the glaciers is melted by ocean warmth. "There's an entrenched view in the public community that glaciers only lose ice when icebergs calve off," says Eric Rignot at the University of California, Irvine. "Our study shows that what's happening beneath the water is just as important."  link
May 2009: Melting of the Greenland ice sheet this century may drive more water than previously thought toward the already threatened coastlines of New York, Boston, Halifax, and other cities in the northeastern United States and Canada, according to new research led by the National Center for Atmospheric Research (NCAR). link    

The Tibetan Plateau - The Third Pole. Because the Tibetan Plateau and its environs shelter the largest perennial ice mass on the planet after the Arctic and Antarctica, it has come to be known as “the Third Pole.” Due to climate change, the roughly 1.7-mile-long Baishui Glacier No. 1 could well be one of the first major glacial systems on the Tibetan Plateau to disappear after thousands of years. The glacier, situated above the honky-tonk town of Lijiang in southwest China, has receded 830 feet over the last two decades and appears to be wasting away at an ever more rapid rate each year. It is the southernmost glacier on the plateau, so its decline is an early warning of what may ultimately befall the approximately 18,000 higher-altitude glaciers in the Greater Himalayas as the planet continues to warm. Temperatures on the Tibetan plateau are rising much faster than the global average. Respected Chinese glaciologist Yao Tandong recently warned that, given present trends, almost two-thirds of the plateau’s glaciers could well disappear within the next 40 years. link  Some scientists have observed mountain ranges where glaciers there were advancing. Under debate is whether this is a phenomenon called glacial "surge" caused by melt water underneath the glacier lubricating its ground contact and causing it to move forward. This is different from a real advance of a glacier, which is caused by an increase in the volume of ice. link

January 2011: Glaciers in the South American Andes are melting faster than many scientists predicted; some climate change experts estimate entire glaciers across the Andes will disappear in 10 years due to rising. Peru is home to 70% of the world’s tropical glaciers, which are also found in Bolivia, Ecuador and Chile. Peru’s 18 mountain glaciers, including the world’s largest tropical ice mass, are critical to the region’s water sources for drinking, irrigation and electricity. link

Types of glaciers and how they are formed - link  
National Snow and Ice Data Center:  in-depth look at glaciers -  link
In pictures - the world's melting glaciers

August 2010: Arctic ice melt to cost up to $24 trillion by 2050. Arctic ice melting could cost global agriculture, real estate and insurance from $2.4 trillion to $24 trillion by 2050 in damage from rising sea levels, floods and heatwaves according to economist Eban Goodstein  who co-authored a report called “Arctic Treasure, Global Assets Melting Away.” The report, reviewed by scientists and economists provides the first attempt to monetize the cost of the loss of one of the world’s great weather makers. link   

Polar Bears: are they declining or flourishing?   At the most recent meeting of the IUCN Polar Bear Specialist Group (Copenhagen, 2009), scientists reported that of the 19 subpopulations of polar bears, eight are declining, three are stable, one is increasing, and seven have insufficient data on which to base a decision. (The number of declining populations has increased from five at the group's 2005 meeting.)       It is true that polar bear populations rebounded after over-hunting was restricted, but that situation has nothing to do with the threat polar bears now face: the loss of the sea ice habitat essential to their survival. link May 2010: Latest study concludes that climate change will trigger a dramatic and sudden decline in the number of polar bears. The research (published in the journal Biological Conservation) is the first to directly model how changing climate will affect polar bear reproduction and survival. These changes will happen suddenly as bears pass a 'tipping point'.  link In a new study (Journal of Zoology), scientists compared bear skulls from the early 20th century with those from the latter half of the century describing changes in size and shape that could be linked an increase in pollution and the reduction in sea ice. Physical "stress" caused by pollutants in the bears' bodies, and the increased effort needed to find food, could limit the animals' growth, the team said. Polar bears are one of the most polluted mammals on the globe according to Christian Sonne, University of Aarhus. link  More Q&A on Polar bears  here June 2011: The truth about polar bears and climate change: National Geographic interview.