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Large-scale storm systems are the dominant weather phenomenon during the cold season in the United States. Although the analysis of these storms is complicated by a relatively short length of most observational records and by the highly variable nature of strong storms, some clear patterns have emerged.112 [Kunkel et al., 2008] Storm tracks have shifted northward over the last 50 years as evidenced by a decrease in the frequency of storms in mid-latitude areas of the Northern Hemisphere, while high-latitude activity has increased. There is also evidence of an increase in the intensity of storms in both the mid- and high-latitude areas of the Northern Hemisphere, with greater confidence in the increases occurring in high latitudes.112 [Kunkel et al., 2008] The northward shift is projected to continue, and strong cold season storms are likely to become stronger and more frequent, with greater wind speeds and more extreme wave heights.68 [Gutowski et al, 2008]

The northward shift in storm tracks is reflected in regional changes in the frequency of snowstorms. The South and lower Midwest saw reduced snowstorm frequency during the last century. In contrast, the Northeast and upper Midwest saw increases in snowstorms, although considerable decade-to-decade variations were present in all regions, influenced, for example, by the frequency of El Niño events.112 [Kunkel et al., 2008]

Then we have this apparently as yet unpublished research presented by Dr James Overland of the NOAA/Pacific Marine Environmental Laboratory at the recent International Polar Year Oslo Science Conference (IPY-OSC) where he was chairing “a session on polar climate feedbacks, amplification and teleconnections, including impacts on mid-latitudes.” “Cold and snowy winters will be the rule, rather than the exception,” says Dr James Overland…. Continued rapid loss of sea ice will be an important driver of major change in the world’s climate system in the years to come…. “While the emerging impact of greenhouse gases is an important factor in the changing Arctic, what was not fully recognised until now is that a combination of an unusual warm period due to natural variability, loss of sea ice reflectivity, ocean heat storage and changing wind patterns working together has disrupted the memory and stability of the Arctic climate system, resulting in greater ice loss than earlier climate models predicted,” says Dr Overland. “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,” he says.

Even though these storms occurred during warmest winter on record, I think the best way to talk about it until Overland publishes his work is the way NCAR’s Kevin Trenberth did on NPR (audio here): RENEE MONTAGNE, host:  With snow blanketing much of the country, the topic of global warming has become the butt of jokes. Climate skeptics built an igloo in Washington, D.C. during last weeks storm and dedicated it to former Vice President Al Gore, who’s become the public face of climate change. There was also a YouTube video called “12 Inches of Global Warming” that showed snowplows driving through a blizzard.For scientists who study the climate, it’s all a bit much. As NPRs Christopher Joyce reports, they’re trying to dig out. CHRISTOPHER JOYCE: Snowed-in Washington is where much of the political debate over climate change happens. So it did not go unnoticed when a Washington think-tank that advocates climate action had to postpone a climate meeting last week because of inclement weather. That kind of irony isnt lost on climate scientists. Most don’t see a contradiction between a warming world and lots of snow. Heres Kevin Trenberth, a prominent climate scientist at the National Center for Atmospheric Research in Colorado. Mr. KEVIN TRENBERTH (Scientist, National Center for Atmospheric Research): The fact that the oceans are warmer now than they were, say, 30 years ago, means there’s about, on average, 4 percent more water vapor lurking around over the oceans than there was, say, in the 1970s. JOYCE: Warmer water means more water vapor rises up into the air. And what goes up, must come down. Mr. TRENBERTH: So one of the consequences of a warming ocean near a coastline like the East Coast and Washington, D.C., for instance, is that you can get dumped on with more snow, partly as a consequence of global warming. JOYCE: And Trenberth notes that you don’t need very cold temperatures to get big snow. In fact, when the mercury drops too low, it may be too cold to snow. There’s something else fiddling with the weather this year: a strong El Nino. That’s the weather pattern that, every few years, raises itself up out of the western Pacific Ocean and blows east to the Americas. It brings heavy rains and storms to California and the South and Southeast. It also pushes high-altitude jet streams farther south, which brings colder air with them. Trenberth also says El Nino can lock in weather patterns like a meteorological highway, so that storms keep coming down the same track. True, those storms have been big ones – record breakers. But meteorologist Jeff Masters, with the Web site Weather Underground, says it’s average temperatures — not snowfall — that really measure climate change. There’s more water vapor lurking around the oceans, and whatever the proximate cause of any one snow storm, there is little doubt that global warming means the overwhelming majority of East Coast storms will be sweeping in more moisture and dumping it on the ground.

Interestingly, this particular glacier has been retreating especially rapidly in recent years. As the below image shows, the ice front receded more 27 miles in 160 years, but in recent years the ice loss rate has increased, with six miles of retreat observed in just the past decade.

"Fog prevents water loss from Redwoods in summer, and is really important for both the tree and the forest," he said. "If the fog is gone, we might not have the Redwood forests we do now."

Ice extent for July 2010 was the second lowest in the satellite record for the month. The linear rate of decline of July ice extent over the period 1979 to 2010 is now 6.4% per decade.

Older, thicker ice melting in the southern Beaufort Sea This past winter's negative phase of the Arctic Oscillation transported old ice (four, five, and more years old) from an area north of the Canadian Archipelago. The ice was flushed southwards and westward into the Beaufort and Chukchi seas, as noted in our April post. Ice age data show that back in the 1970s and 1980s, old ice drifting into the Beaufort Sea would generally survive the summer melt season. However, the old, thick ice that moved into this region is now beginning to melt out, which could further deplete the Arctic’s remaining store of old, thick ice. The loss of thick ice has been implicated as a major cause of the very low September sea ice minima observed in recent years.

Hampton Roads in southeastern Virginia is unusually vulnerable. It is flat, and its land is sinking. It has nearly 2 million residents. It is home to popular beaches, waterfront homes, military bases, a huge tourism industry and ecologically valuable marshes.

"Hampton Roads is one of the most vulnerable regions in the United States to sea-level rise, in terms of population and assets at risk," said Eric J. Walberg, a former staff member for the Hampton Roads Planning District Commission.

Rising sea levels around the world are attributed to warming. When water warms, it expands. Melting polar ice sheets also raise the waters. In Virginia, sea levels are rising faster than the global average because the land is sinking

The sea level in this region has been rising about a foot a century -- the highest rate on the East Coast. Scientists project a potentially devastating rise of 2 to 7 feet by 2100.

Many of the piers at the Norfolk Naval Station were built around World War II. During storms or even higher-than-normal tides in recent years, the water began to rise so high that it flooded low-lying areas of the base and covered utility lines, including high-voltage electrical cables, suspended beneath the old piers. That meant frequent losses of power and other services to the base's ships. "Sea-level rise was having a negative impact on the readiness of the combat forces at the base," said Joe Bouchard, the base's commander from 2000 to 2003.

The Navy was already planning a multimillion-dollar project to replace the aging piers at Norfolk, the world's largest naval base. To cope with the rising waters, Navy engineers designed double-deck piers with the utility lines suspended from the main, upper deck, about 20 feet above sea level.

Cmdr. Wendy L. Snyder, a Defense Department spokeswoman, acknowledged that flooding occurs at the Norfolk and Langley bases. The department is concerned and is studying the problem, she said. "We are going to assess the impacts of climate change for all of our installations." As for possible base closings in Hampton Roads, Snyder said she did not want to speculate.

A powerful storm hit Virginia's coast in 1933. But the less-powerful Hurricane Isabel in 2003 -- which became a tropical storm about the time it entered Virginia -- caused similar flooding because the sea level by then had risen 9 to 10 inches. Isabel gained extra destructive power by sending its storm surge inland on higher waters, Hershner said. Isabel caused hundreds of millions of dollars in damage. On top of all that, scientists predict global warming will cause more-powerful storms in coming decades. And in Hampton Roads, more and more people are building near the shore, putting themselves and their property at risk.

Low-lying parts of Hampton Roads flood now from fairly routine storms and tides, said Skip Stiles, director of Wetlands Watch, a Norfolk environmental group. "Anywhere you go, people have stories" about how the water comes up higher than it used to.

The havoc has brought total economic losses in the nine provinces to 14.5 billion yuan (€1.7 billion), and affected 535,500 hectares of crops, further blighting food supply in the region. The conditions have also led to the collapse of 68,000 houses.

The meteorological bureau was forecasting more thunderstorms overnight and it was expecting rainfall of 100-180 millimetres in many areas, rising to over 200 millimetres in others.

“The scope and intensity of the rain have increased,” the office said on its website yesterday.This is effectively three times the usual level of rain in the region.Climate change has meant that each year the flooding gets worse, while the droughts are also worsening.

Still, the collapse of the thermosphere was bigger than the sun's activity alone can explain. Emmert suggests that the increasing amounts of carbon dioxide making its way into the upper atmosphere might have played a role in the anomaly.

Carbon dioxide acts as a coolant in the upper atmosphere, unlike in the lower atmosphere, shedding heat via infrared radiation. As carbon dioxide levels build up on Earth, it makes its way into the upper levels and magnifies the cooling action of the solar minimum, Emmert said. As carbon dioxide gradually builds up, "we expect every solar minimum to be a little lower, and then this solar minimum comes along, but instead it's a lot lower. And that's pretty surprising," said Stanley Solomon, a senior scientist with the National Center for Atmospheric Research who wasn't directly involved in this research.

But, Emmert said, even taking into account the solar activity and carbon dioxide buildup doesn't fully account for this abnormal collapse. Despite the puzzling anomaly, the collapse of the thermosphere is unlikely to have a direct effect on our daily lives, said Solomon. "It's not going to affect the weather, or you won't be able to tell that this is going on by looking at the sky. It's not going to look any darker," he said.

But the contraction of the thermosphere can affect the drag on satellites and space junk orbiting at those levels. "Debris that's up there stays up longer. The amount of orbital debris is a concern for space navigation. There is concern that space debris is building up," Emmert said. The abnormal change in the thermosphere may also affect other layers of the atmosphere, and though less certain, can result in slight disruptions of satellite communications, including global-positioning system signals, Solomon said. Emmert said there were still other possibilities unaccounted for that could have contributed to this phenomenon.

"It could be that we're underestimating the effects [of carbon dioxide] somehow. It could be because there were some physics that we're missing in the region of the atmosphere below the thermosphere, which quickly affects the thermosphere," he said. The researchers say they will continue to monitor the upper atmosphere, which is already rebounding. "So we're probably going to work in the next couple of years to try and unravel this," Emmert said.

Ron Kwok of the Jet Propulsion Laboratory (JPL) reports that Nares Strait, the narrow passageway between northwest Greenland and Ellesmere Island is clear of the ice “arch" that usually plugs southward transport of the old, thick ice in the Lincoln Sea. Typically the ice arch forms in winter and breaks up in early July. This year the arch formed around March 15th and lasted only 56 days, breaking up in May. In 2007 the ice arch did not form at all, allowing twice as much export through Nares Strait than the annual mean. Although the export of sea ice out of the Arctic Ocean through Nares Strait is very small in comparison to the export through Fram Strait, the Lincoln Sea contains some of the Arctic’s thickest ice.

Yesterday’s temperature in Moscow was the highest since Russia began keeping records 130 years ago, according to the website of the Hydrometeorological Monitoring Service. The previous high was 36.8 degrees in July 1920, during the Civil War. The temperature may rise to 38 degrees on July 29, according to Gidromettsentr, the state weather service. Russia, the world’s third-biggest wheat exporter, will harvest about 80 million metric tons of grain this season, 17 percent less than last year, according to Moscow-based researcher SovEcon. Grain prices rose as much as 33 percent last week on drought concerns, SovEcon said on its website. Drought is likely to have a bigger impact on prices in Russia than in other countries, Orlova said. Food accounts for 38 percent of the consumer price index in Russia, compared with 15 percent in the U.S. and 32 percent in China, Alfa estimates.