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July sea ice second lowest: oldest ice begins to melt Arctic sea ice extent averaged for July was the second lowest in the satellite record, after 2007. After a slowdown in the rate of ice loss, the old, thick ice that moved into the southern Beaufort Sea last winter is beginning to melt out.

Average ice extent for July was 8.39 million square kilometers (3.24 million square miles), 1.71 million square kilometers (660,000 square miles) below the 1979 to 2000 mean, but 260,000 square kilometers (100,000 square miles) above the average for July 2007, the lowest July in the thirty-two-year satellite record.

The daily rate of decline for July was 77,000 square kilometers (29,700 square miles) per day, close to the 1979 to 2000 average of 84,400 square kilometers (32,600 square miles).

Greenland's ice is melting so quickly the land underneath is rising at an accelerated pace. Researchers said some coastal areas are rising by nearly 1 inch per year

"It's been known for several years that climate change is contributing to the melting of Greenland's ice sheet," Professor Tim Dixon, who led the study, said. "What's surprising, and a bit worrisome, is the ice is melting so fast that we can actually see the land uplift in response. Even more surprising, the rise seems to be accelerating, implying melting is accelerating."

Greenland glacier calves island 4 times the size of Manhattan

A University of Delaware researcher reports that an “ice island” four times the size of Manhattan has calved from Greenland's Petermann Glacier. The last time the Arctic lost such a large chunk of ice was in 1962.

“In the early morning hours of August 5, 2010, an ice island four times the size of Manhattan was born in northern Greenland,” said Andreas Muenchow, associate professor of physical ocean science and engineering at the University of Delaware's College of Earth, Ocean, and Environment.

Based on satellite measurements taken during a baseline period from 1980-2000, the ice covering the Arctic Ocean ranges from an average late winter peak of about 6 million square miles (more than twice the area of the lower 48 states), to a typical late summer minimum of well less than half of that. The melt is in full swing by the summer solstice each year, when the baseline ice extent averages about 4.6 million square miles. But this year, according to NASA and the National Snow and Ice Data Center , the melt-back reached that level by June 1, three weeks early, and since that time, has been at record low levels for the period. This is particularly remarkable because throughout April, daily ice extents hovered very close to average baseline levels (as noted at the time by some commentators eager to suggest the globe is not warming). In other words, the ice retreated with exceptional speed this May — a speed close to the average melt rate of July.

Ugandan wildlife authorities say the ice cap on the country's western Rwenzori mountain range has split after extensive melting caused by global warming.Nelson Guma says ice covering Mount Margherita, the second highest peak in Africa, has melted forming a large crevasse some 6 metres (nearly 20 feet) wide.Guma said Tuesday the split occurred on the climbing route to Mount Margherita and that tourists can no longer climb that peak, but authorities are working to create another route to the peak. The East African peak has been named a UNESCO World Heritage Site.Environmental protection officer Henry Mujuzi says that because of global warming, the ice cap, which in the 1950s had covered four square miles, now covers less than a square mile.

From NASA’s eyes in the sky, this is a view of the west coast of Greenland downloaded earlier today, looking down on the Ilulissat Icefjord — the outlet for the Jakobshavn Isbrae, the biggest outlet glacier in Greenland and the largest in the northern hemisphere.

I’m posting it to show the numerous large lakes of glacial meltwater that have appeared on top of the ice sheet over recent weeks. At the edge of the ice sheet, the winter snow has melted revealing the greyer ice underneath, but as you climb up the ice away from the coast you get back up into unmelted snow (bottom right). And there are lakes like this a very long way up the west coast, all primed to deliver their water down through moulins to the base of the sheet and thence out to sea, or over the surface in glacial rivers.

Last winter's big snowfall and cold temperatures in the eastern United States and Europe were likely caused by the loss of Arctic sea ice, researchers concluded at the International Polar Year Oslo Science Conference in Norway last week.Climate change has warmed the entire Arctic region, melting 2.5 million square kilometres of sea ice, and that, paradoxically, is producing colder and snowier winters for Europe, Asia and parts of North America. "The exceptional cold and snowy winter of 2009-2010 in Europe, eastern Asia and eastern North America is connected to unique physical processes in the Arctic," said James Overland of the NOAA/Pacific Marine Environmental Laboratory in the United States. "In future, cold and snowy winters will be the rule rather than the exception" in these regions, Overland told IPS.

Temperatures in January were -2C over the water, while the land was -25C, making conditions far windier and producing more snowfall than normal. Heavy snow on the remaining ice insulates it from the cold air, preventing it from thickening during the long winter.

This huge mass of warmer air over the Arctic in the late fall not only generates more wind and snow locally, several studies have now documented the impacts on global weather patterns. The winter of 2005-6 was the coldest in 50 years in Japan and eastern Eurasia, reported Meiji Honda, a senior scientist with the Climate Diagnosis Group at Japan's Agency for Marine-Earth Science and Technology. Honda's studies show that the air over the Arctic was quite warm in the fall of 2005, which altered normal wind patterns, pushing the jet stream further south and bringing arctic cold to much of Eurasia and Japan. He also documented the same mechanism for the colder winters of 2007-8 and 2009-10, he told participants. In eastern North America, the same conditions of 2007-8 produced increased precipitation and colder temperatures in the winter. As the sea ice declines, big impacts are likely to be seen in this region, said Sara Strey of the University of Illinois.

"June is going to be a new record low (for sea ice extent)," said Julienne Stroeve of the National Snow and Ice Data Center. The rate ice has been receding is also faster than any other June on record, she said, as was May.

ISSUED BY ENVIRONMENT CANADA ON 01 JULY 2010.

Taking all of the above into consideration, the current pack ice pattern in the Western Arctic resembles that normally seen in the last two weeks of July. The consolidated sea ice pattern in the Central Arctic at the end of June resembles conditions normally seen at this time, except for the region spanning Barrow Strait to M'Clure Strait which more closely resembles that seen at the end of July or in early August.

The 3-mile- (4,884-meter-) high glacier was pounded by rain every afternoon during the team's 13-day trip, something the American scientist has never encountered in three decades of drilling ice cores. He lay awake at night listening to the water gushing beneath him. By the time they were ready to head home, ice around their sheltered campsite had melted a staggering 12 inches (30 centimeters). "These glaciers are dying," said Thompson, one of the world's most accomplished glaciologists. "Before I was thinking they had a few decades, but now I'd say we're looking at years."

The mountain has lost about 80 percent of its ice since 1936 - two-thirds of that since the last scientific expedition in the early 1970s. Thompson says he thinks temperatures are rising twice as fast in high altitudes as at the earth's surface, which, if true, could have broad implications on people who depend on glaciers for water during the dry season, such as in the Himalayas.

Geoffrey Hope, a professor at Australian National University who took part in the 1971 expedition to Puncak Jaya, noted that Papua has the wettest mountain region in the world, so high precipitation levels didn't come as a great surprise. Still, his own experience was markedly different. "The roof of our marque tent fell in on many evenings due to the weight of the snow," he recalled, "and all water coming from the glacier would freeze by 8 p.m. each night."

the ice has been melting earlier in the spring and forming later in the autumn, so that the bears are now spending on average three more weeks on land per year, without food, than they did three decades ago, the researchers say. As a consequence, their body weight in that time has dropped by 60lb, females have lost 10 per cent of their body length, and the west Hudson Bay population has declined from 1,200 animals to 900.

POQUOSON -- Hurricane Isabel flooded Sandy Firman's house in 2003, and now routine storms drive water into the roads and marshes close by. Several homes in this low-lying city, including Firman's, have been elevated about 10 feet to keep them above the ever-closer waters. "We used to not have it like that," said Firman, who has lived in Poquoson all of his 46 years. "But something has changed around here." One big thing that has changed is the sea level, which is rising -- an increase blamed on global warming.

In southeastern Virginia, the rising sea is a problem now, and scientists expect it to get much, much worse.

During the last ice age thousands of years ago, the weight of glaciers pushed down land in what is now the northern U.S. When those glaciers receded, that northern land began to rise, and land here started sinking, as if Virginia were on the end of a see-saw after the other rider got off. Throughout most of the 20th century, the sea level in southeastern Virginia rose about twelve-hundredths of an inch a year -- or 12 inches per century. But over the past two decades or so, the rate appears to have doubled in places. About half of that increase seems to be due to the sinking of land, and half to global warming, said Carl Hershner, a professor at the Virginia Institute of Marine Science. "And the forecast -- this is the scary part -- is for that acceleration to rise," Hershner said. Scientists say the future increases will be caused almost entirely by climate change. "We will still be sinking," Hershner said, "but that will be a smaller and smaller fraction of the change we experience."

while weather patterns are some of the most visible indicators of climate change, we are able to look at other patterns in the ecosystem as equally important measurements.  Among these patterns are jellyfish blooms, which are proliferating at an incredible pace. 

There are a number of factors contributing to the increase of jellyfish blooms, most of which are linked to global warming.  Jellyfish are thriving due to warmer and saltier waters as well as an increase in plankton growth.  In addition, overfishing has created a niche for jellyfish to exploit.  In years before predators were consuming much more of the ocean’s nutrients.  Now however, there is less competition leaving more for jellyfish.  This is also the case with agricultural runoff, where jellyfish are able to capitalize on the organisms feeding on the bacteria.  The current trend in climate change shows that the ice cover is melting much later in the spring, spawning more rapid and increased amounts of plankton growth.  There are various theories based on this evidence, but perhaps the strongest supports the idea that increased sunlight is favorable for the plankton.  This is especially true in colder regions such as the Bearing Sea, where scientists and fisherman alike have noticed drastic increases in jellyfish blooms.  But despite recent awareness, population control will only be a reality once the global climate patterns stabilize. For most, summer draughts mean hot days and dry gardens.  For jellyfish, however, it means saltier waters.  As rain becomes less frequent there is less fresh water entering the ocean.  Although it’s not the case with all jellyfish, most will benefit from a higher salt content.  This also relates to other predators and fish species, which are less tolerant of the salt increase and will often move from the coast into deeper, less salty waters.  As the ocean gets warmer and the water level rises, the jellyfish survival rate also goes up.  It creates the right conditions for jellyfish blooms to prosper, which results in a longer span of migration.  Now there are jellyfish species that are being labeled invasive.  Beachgoers have to swim with a new element of caution, unable to know which new species has moved in, and which has left. 

the glaciers that melt into the Ganges are shrinking, according to the most detailed analysis yet of how climate change will affect key Asian glaciers.

the 100-metre-thick glaciers that feed the Ganges are thinning, at a rate of 22 centimetres per year.

Thursday Flood Risk (and the most severe 30 days in Minnesota history?)

Paul's Star Tribune Outlook for the Twin Cities and all of Minnesota

we just lived through an incredible 30-day period. According to the local National Weather Service Office in Chanhassen we experienced 395 severe storms between June 17 and July 17. That compares to 120 severe storms in all of 2009! So in a mere 30 days we saw more than 3 TIMES more severe weather than we did all of last year.