A look at weather extremes and the big-picture climate connections.

2010 Russian Heatwave More Extreme Than Previously Thought

Tourists brave the hot weather to see St. Basil Cathedral in Moscow last summer amidst the worst European heatwave on record. Credit: Alex Wolf/flickr.

It’s safe to say the sweltering heat wave that struck western Russia last summer brought the hottest temperatures anyone from the region could remember. After all, the daytime temperatures in Moscow surged past 100°F, and prior to last summer, the city’s all-time high temperature had never reached the century mark (with records going back as far as 1879).

The Russian heatwave was a record-breaking event by nearly any description. Now, months later, there is a new perspective on just how rare the summer of 2010 was across Europe.

Prior to 2010, the most severe heat wave on record for the continent was in 2003, when two stretches of exceptionally hot weather blanketed western European countries like France, Spain, and Germany. According to a new study that compares both the severity and areal extent of these two so-called “mega-heatwaves,” last summer’s event was more extreme than the one seven years earlier. Though not as high as those seen in 2003 (when parts of France were well above 100°F for days), the temperatures in Russia last summer were much higher than the region’s average temperatures. Heatwaves are actually measured according to how hot the temperatures get relative to what is seen on average for that time of year in a given region.

“2010 was more extreme (than 2003) just in terms of terms of temperature anomaly alone,” says climate scientist Erich Fischer from ETH Zurich in Switzerland, one of the study’s co-authors. Fischer says the 201...


Globe Stayed Warmer Than Average in February, NOAA Reports

According to NOAA’s National Climatic Data Center (NCDC) global climate analysis released today, 2011 continues to show warmer than average conditions across most of the globe… with some notable exceptions. Cooler than average conditions were present across the eastern half of the United States, as well as most of Europe and Russia during January and February 2011.

Temperature departures from average during February 2011. Credit: NCDC.

At 0.72°F above the 20th century average of 53.9°F, the combined global land and ocean average surface temperature for February 2011 tied for the 17th warmest such value on record (records began in 1880). The combined global land and ocean average surface temperature for meteorological winter (December 2010 to February 2011) was the 16th warmest such period on record. It’s also notable that Arctic sea ice extent for February 2011 tied with 2005 as the lowest February extent on record at 8.2 percent below the 1979-2000 average.

Note that these temperature rankings are somewhat cooler than temperatures just a few months ago. Last year, for example, was tied for the warmest year on record. The relatively cooler temperatures can be attributed in part to ongoing La Niña conditions, the periodic cooling of the eastern equatorial Pacific Ocean. In addition, the cooler than average conditions that prevailed in the eastern US through at least the first half of the winter were largely dominated by the configuration of a natural climate cycle known as the Arctic Oscillation.

The worldwide land surfa...


Arctic Exploration for Climate Science

Four explorers set off in the Arctic as part of the 2011 phase of the Catlin Arctic Survey. Credit: Catlin Arctic Survey.

In recent years, there have been many indications that the Arctic is suffering the effects of climate change more rapidly and seriously than almost any other region of the world. In particular, temperatures at the top of the planet have been rising much faster than the global average, and all that additional heat has melted vast quantities of Arctic sea ice.

Scientists have spotted these trends thanks to satellite data and other techniques, but there is still an awful lot that researchers don’t know about how the Arctic is responding to global warming. It’s no surprise, really; the Arctic is a harsh environment and it is difficult for scientists to get out there and study it in-person. But some of this on-the-ground data is exactly what climate scientists need in order to get a more complete picture of how the Arctic is changing and what ramifications there might be for the rest of the world. The quest for such data underpins a unique collaboration between scientists and explorers, known as the Catlin Arctic Survey, which just kicked off its third year. The survey is sponsored by Catlin Group Limited, an international insurance company.

Earlier today, a group of four seasoned explorers set off into the Arctic wilderness, armed with scientists’ tools to monitor the environment. Measuring changes in Arctic Ocean temperatures and salt-water content, the team will be trekking for 10 days before returning to a base camp at Resolute Bay in the northernmost...


Arctic Sea Ice Ties Another Record Low

Monthly February ice extent for 1979 to 2011 shows a decline of 3.0 percent per decade. Credit: NSIDC.

The decline of the Arctic's sea ice cover is one of the most visible manifestations of global climate change. During the past few decades, the rapidly warming Arctic region has seen a steepening decline in its ice cover, particularly during the summer months, to the point where the famed Northwest Passage and Northern Sea Route were both open for navigation at the end of the 2010 summer melt season —possibly heralding a new age of human activities, including shipping and oil drilling, in the Far North.

Although it is doing so at a lesser rate, wintertime sea ice extent is also declining, and this year has been no exception. Thanks in part to weather patterns that have kept much of the Arctic region unusually warm, last month, sea ice extent reached the lowest level on record for the month of February, a record shared with February 2005. According to the National Snow and Ice Data Center (NSIDC) in Boulder, Colo., February ice extent was low in both the Atlantic and Pacific portions of the Arctic — with the most pronounced departures from average in the Labrador Sea and Gulf of Saint Lawrence.

Here's more on February sea ice decline, from NSIDC scientists:

"While ice extent has declined less in winter months than in summer, the downward winter trend is clear. The 1979 to 2000 average is 15.64 million square kilometers (6.04 million square miles). From 1979 through 2003, the February extent averaged 15.60 million square kilometers (6.02 million square...


Loading the Dice for Heavier Snowfall

  Data from the National Weather Service's analysis of snow depth in the U.S., showing how much snow was on the ground following a January 10-12 snowstorm. Credit: NOAA

It’s been a snowy winter across much of the U.S., particularly in the Midwest and in states like Oklahoma and Arkansas, where snowfall records were recently broken. Southern states like California, Georgia, and New Mexico (all but Florida, really) also experienced snow this winter. And with more wintry conditions forecast for the coming weeks (meteorological winter ended on Feb. 28, but calendar year winter continues until March 19), yesterday’s press briefing from the Union of Concerned Scientists (UCS) — that heavier and more frequent snowstorms are consistent with climate change — seems perfectly timed.

In reality, it’s probably just lucky timing.

During a telephone press conference, experts at UCS, a non-profit environmental organization, as well as outside the group talked about the heavy snow-climate change connection. The message wasn’t that all this snow could be blamed on global warming. Instead, the experts emphasized that research suggests that snowy winters, like those of 2010-2011 and 2009-2010, could become more common in the future, as the climate warms and more water vapor is put into the atmosphere.

During the call, meteorologist Jeff Masters of Weather Underground, a private weather forecasting company, explained:

As the Earth gets warmer and more moisture gets absorbed into the atmosphere, we are steadily loading the dice in favor of more extreme storms in all seasons, capable of causing greater impacts on society.