Connecting the Dots Between Russian Heat Wave and Asian Floods

Published: August 11th, 2010

Andrew Freedman

Depending on your news source, the weather around the world has either gone “berserk,” haywire, off its rocker, or plain old extreme.

Take a Sky News headline from August 10, for example: “Berserk Weather Causes Worldwide Chaos.” It’s a quintessential example of how the media sensationalizes unusual weather events. (My compliments go to the author, however, for managing to use the words “berserk” and “chaos” in the same sentence).

Despite the excessively alarming tone of some of the stories, it’s difficult to avoid being at least somewhat concerned by the facts: thus far 2010 ranks as the warmest year in recorded history. Western Russia continues to suffer through its worst heat wave in generations that is killing thousands and brought the first-ever 100-degree plus weather to Moscow – twice – along with rampaging wildfires that are polluting vast areas of the country and halting Russian wheat exports.

The widespread influence of the fires on Russia’s air quality can be seen in this image from NASA, showing atmospheric carbon monoxide levels. The heat and fires have led to elevated levels (in red) of this harmful gas in Western Russia. Credit: NASA.

Meanwhile, in Pakistan an unusual configuration of the Asian Monsoon, which typically douses Bangladesh and India with heavy rain during the summer months, has brought torrential downpours to normally dry areas, affecting millions of people. Meteorologist Jeff Masters has many more details on his blog at Weather Underground.

Oh, and did I mention that as many as 17 countries may have set new all-time high temperature records so far in 2010? Those are not exactly easy records to break, either.

The Economist and Wired Science have published excellent analyses of the immediate causes of the wild weather of late, and the potential role that long-term climate change may be playing in making these events more likely to occur. None of these events has been—or ever could be—definitively attributed to human-caused climate change, but there are intriguing climate change connections.

The Economist sums up the relationship between climate change and the ongoing extreme events succinctly with these two sentences: “The two events [Russian heat wave and flooding in Pakistan] are linked by a large-scale pattern of atmospheric circulation which is producing a particularly persistent area of high pressure over Russia. They are also linked in both being the sort of events climate scientists predict more of in a warming world.”

Unfortunately, there may be another region that will feel the effects of the Russian heat wave, and it’s an area that is already undergoing major changes due to a warming climate.

According to Reuters, scientists are warning that soot from the raging Russian wildfires may have a warming impact in the Arctic, where sea ice is in the midst of another abnormally extensive melt season. As of the beginning of this month, sea ice was on track to, by the end of the melt season, reach the second lowest extent since satellite records began in 1979.

Trend in sea ice extent in 2010, as of August 10, 2010. Credit: National Snow and Ice Data Center.

A full 40 percent of soot emissions comes from uncontrolled sources like wildfires, whereas the rest comes from human activities such as burning diesel fuel. Components of soot, such as black carbon, can warm the atmosphere and melt ice and snow by absorbing greater amounts of solar energy. Black carbon in soot darkens bright white snow and ice surfaces, which increases the amount of solar radiation absorbed, and leads to greater melting of snow and ice.

The geographical extent of the wildfire smoke was driven home by this image from the U.S. National Oceanic and Atmospheric Administration (NOAA).