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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Then we have this apparently as yet unpublished research presented by Dr James Overland of the NOAA/Pacific Marine Environmental Laboratory at the recent International Polar Year Oslo Science Conference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.

Scattered power outages affected customers up and down the coast and usage approached record

levels. In the Washington, D.C., area, nearly 1,000 customers were without power Wednesday, while New Jersey's largest utility, Public Service Electric & Gas, reported about 6,300 customers without power. Consolidated Edison in New York said it was working to restore power to about 6,300 customers, down from outages to 18,700 customers Tuesday.

The heat also forced nursing homes with power problems to evacuate and buckled highways near Albany and in the Philadelphia area. On New York's Long Island, a radio station was distributing free bottled water to day laborers, while human services workers in Pittsburgh were doing the same for the homeless there.

Transportation officials cut the speed of commuter trains in suburban Washington, D.C., and New York when the tracks got too hot. Extreme heat can cause welded rails to bend under pressure. Some New Jersey trains were canceled and rail-riders were advised to expect delays.

In Park Ridge, N.J., police evacuated a nursing home and rehabilitation center after an electrical line burned out Tuesday evening. In Maryland, health officials moved all 150 residents out of a Baltimore nursing home whose operators didn't report a broken air conditioner. The state learned of the home's troubles when a resident called 911 Tuesday

Residents of two Rhode Island beach towns, Narragansett and South Kingstown, were hit with an added layer of inconvenience: They were banned from using water outdoors and were asked to boil and cool their water before using it. The high temperatures combined with the busy holiday weekend for tourists created higher-than-expected demand, causing water pressure to drop and increasing the chance of contamination.

With people cranking up their air conditioners Wednesday, Valley Forge, Pa.-based PJM Interconnection — which operates the largest electrical grid in the U.S. — urged users to conserve electricity as much as possible, especially in the peak afternoon hours. PJM's grid covers about 51 million people in 13 states and the District of Columbia.

Meteorologists in some places began calling the current hot stretch a heat wave, defined in the Northeast as three consecutive days of temperatures of 90 or above.

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.

More southerly parts of the Gulf have been feeling the heat too. An official at Bahrain¡¯s ministry of health said Salami Medical Complex¡¯s accident and emergency department has admitted between five and 15 cases of heat exhaustion every day since last week. ¡°Normally, we¡¯d have one to two cases every day. Bahrain is overheated and the humidity is very high,¡± the official said.

The forecaster on duty at Dubai International Airport said the maximum temperatures of up to 45¢ªC that were recorded yesterday were ¡°quite common¡±, but the minimum temperature of 35.9¢ªC that was recorded at 6am was the highest on record.

The heat wave has put intense pressure on the Gulf¡¯s electricity networks as residents crank up their air conditioners for relief. Kuwait¡¯s power consumption peaked at 10,921 megawatts on Tuesday, close to the network¡¯s maximum capacity of around 11,200MW. If demand outstripped supply, the national control centre would begin cutting off sections of the city.

Sea-level rise is particularly high along the coastlines of the Bay of Bengal and the Arabian Sea, as well as the islands of Sri Lanka, Sumatra and Java, the authors found. The key player in the process is the Indo-Pacific warm pool, an enormous, bathtub-shaped area spanning a huge region of the tropical oceans stretching from the east coast of Africa to the International Date Line in the Pacific. The warm pool has heated by about 1 degree Fahrenheit, or 0.5 degrees Celsius, in the past 50 years, primarily because of human-generated emissions in greenhouse gases.