Global heat wave hits US, reignites climate change debate

Worldwide, the first five months of 2010 were the warmest on record. With the US now getting its share of a heat wave, how will it affect the public perception of climate change?

Beijing hits a near-record 105 degrees Fahrenheit. Boston, New York City, and Philadelphia break 100 degrees and set new daily highs. Meanwhile, in Baghdad and Riyadh, on July 6 it was 113 and 111 degrees, warmer than average but still cooler than in Kuwait, which set the day’s world temperature high at 122 degrees.

The heat has been so intense in China that a plague of locusts is ravaging grasslands and farmlands from Inner Mongolia, and security officials are warning of outbreaks of violence.

Yes, we’re suffering a global heat wave. No, it’s not the apocalypse. But it may be a further sign of climate change.

IN PICTURES: Beating the summer heat

“You can’t say any one heat wave is caused by global warming. But you can say that what global warming does is it makes events just like this more likely,” says Anthony Leiserowitz, director of the Yale Project on Climate Change.

Indeed, 2010 is set to be one of the world’s hottest years on record, according to the US National Oceanic and Atmospheric Association (NOAA). The combined global land and ocean average surface temperature for the first five months of the year was the warmest on record, and 1.22 degrees F warmer than the 20th century average, the NOAA states in its May 2010 State of the Climate Global Analysis.

According to the National Snow and Ice Data Center (NSIDC), the Arctic sea ice extent retreated at a rapid pace in May – 50 percent faster than the average May melting rate. Africa's Lake Tanganyika, the second deepest freshwater lake in the world, is now at its warmest in 1,500 years, according to the journal Nature Geoscience.

Will dog days spur crime?

Crime is known to increase during heat waves, when increased demands on electricity often cause power outages. The New York Times reports that the city police department was prepared to send extra officers to places that had lost power. The Pentagon recently warned of the security ramifications of a warming globe.

“While climate change alone does not cause conflict, it may act as an accelerant of instability or conflict, placing a burden to respond on civilian institutions and militaries around the world,” the Pentagon says in its Quadrennial Defense Review.

A heat wave across Pakistan and India in early June killed more than 1,000 people and pushed the Pakistani city of Mohenjo-daro to 129 degrees F and into the category of hottest places on earth. According to The Guardian, only Al 'Aziziyah, in Libya (136 degrees in 1922), Death valley in California (134 degrees in 1913) and Tirat Zvi in Israel (129 degrees in 1942) are thought to have been hotter.

Changing public attitudes

But if these are all signs of global warming, then why did America’s East Coast get slammed with so much snow this past winter?

Climatologists are careful to highlight that no one weather event is a sign of global warming. Just as the blizzards of this past January and February did not debunk climate change, the current heat wave does not prove climate change.

“What climate change does do is make these kinds of events ever more frequent. It increases the frequency of record-highs,” says Dr. Leiserowitz of Yale University.

At the Yale Project on Climate Change, Leiserowitz measures public attitudes. He says that firm believers won’t have their minds changed on global warming because of a blizzard, just as firm doubters won’t have their minds changed because of a heat wave.

From 2008 to 2009, the Yale Project found that the percentage of doubters had doubled in size to 16 percent of the American public, while the percentage of believers had dropped to 10 percent, from 18 percent in 2008. The current heat wave might reverse that trend, says Leiserowitz.

A permanent change in belief, however, will mean looking at the overall climate pattern and not merely individual storms and heat waves. As Time magazine's "Eco-centric" blogger Bryan Walsh writes, looking at individual weather events is a bit like looking only at individual soccer players.

To use a World Cup analogy ... it's as if the players on the soccer pitch represent the weather, and climate is the team manager. The day-by-day, week-by-week progress of weather is down to countless meteorological factors interacting – some in ways we can predict, others in ways we can't. But climate sets the overall game plan – so some parts of the world will always be hotter or drier or wetter than others, just like the Germans will always be strong and efficient, the Dutch will be creative and the English will always be sad disappointments.

IN PICTURES: Beating the summer heat

Related:

• Air conditioners whir during heat wave, but power systems hold up
• How do you convince people of global warming in a snowstorm?
• It's cold. Does that debunk global warming?