Killer heat "here to stay"
Killer heat waves here to stay, global warming researchers say: Phenomenon not solely to blame but is contributing to the deadly trend
By SETH BORENSTEIN
Associated Press 07-29-06
"A persistent high-pressure system in the upper atmosphere prevents cooler jetstream air from making it into the West, said National Weather Service meteorologist Dennis Feltgen".In Fresno, Calif., the morgue is full of victims from a California heat wave. A combination of heat and power outages killed a dozen people in Missouri. And in parts of Europe, temperatures are hotter than in 2003 when a heat wave killed 35,000.
Get used to it.
•For the next week, much of the nation should expect more "extreme heat," the National Weather Service predicts.
•In the month of August, most of the United States will see "above normal temperatures," forecasters say.
•For the long term, the world will see more and worse killer heat waves because of global warming, scientists say.
The July burst of killer heat waves around the world can't be specifically blamed on global warming.
A persistent high-pressure system in the upper atmosphere prevents cooler jetstream air from making it into the West, said National Weather Service meteorologist Dennis Feltgen.
"You can't tie global warming into one single event," he said.
But global warming has made the nights warmer in general and the days drier, which help turn merely uncomfortably hot days into killer heat waves, said Kevin Trenberth, climate-analysis branch chief at the National Center for Atmospheric Research in Boulder, Colo.
Much of global warming science concentrates on average monthly and yearly temperatures, but studies in the past five years show that climate change is at its most dangerous during extreme events, such as high temperatures, droughts and flooding, he said.
"These (heat) events always occur. What global warming does is push it up another notch," Trenberth said.
And the computer models show that soon, we'll get many more — and hotter — heat waves that will leave the old Dust Bowl records of the 1930s in the dust, said Ken Kunkel, director of the Center for Atmospheric Sciences at the Illinois State Water Survey.
The way to really judge will be when scientists look back a decade from now, not at a single heat wave but at the frequency and extremes of all of them, said Mike Wallace, a professor of atmospheric sciences at the University of Washington. That's when scientists likely will see a statistically significant increase in heat waves and their severity, he said. In fact, he said, that can be seen a bit now.
In the past 25 years, most of the world has seen summer nights getting much warmer with far less evening heat relief, according to a study published earlier this year in the peer-reviewed Journal of Geophysical Research.
George Luber, an epidemiologist who studies heat-wave deaths for the U.S. Centers for Disease Control and Prevention, says the situation is on track to be "the most active one that I can recall" in terms of heat deaths.
A new analysis by Luber this week shows that between 1999 and 2003, the United States averaged nearly 900 heat-related deaths each year. This year, with 132 reported in central California alone, could be worse, he said.