Errant climate may be sign of breakdown, scientists say
Heat waves, fires, and floods fit their predictions
NEW YORK — Floods, fires, melting ice, and feverish heat — from smoke-choked Moscow to water-soaked Iowa and the High Arctic, the planet seems to be having a midsummer breakdown. It is not just a portent of things to come, scientists say, but a sign of troubling climate change already under way.
The weather-related cataclysms of July and August fit patterns predicted by climate scientists, the Geneva-based World Meteorological Organization says, although those scientists always shy from tying individual disasters directly to global warming.
The specialists see an urgent need for better ways to forecast extreme events like Russia’s heat wave and wildfires and the record deluge devastating Pakistan. They will discuss such tools in meetings this month and next in Europe and America, under UN, US, and British government sponsorship.
“There is no time to waste,’’ because societies must be equipped to deal with global warming, says British government climatologist Peter Stott.
He said modelers of climate systems are eager to develop supercomputer modeling that would enable more detailed linking of cause and effect as a warming world shifts jet streams and other atmospheric currents. Those changes can wreak havoc on the weather.
The UN’s network of climate scientists, the Intergovernmental Panel on Climate Change, has long predicted that rising global temperatures would produce more frequent and intense heat waves and more intense rainfalls.
In its latest assessment, in 2007, the Nobel Prize-winning panel went beyond that. It said these trends “have already been observed,’’ in an increase in heat waves since 1950, for example.
Still, climatologists generally refrain from blaming warming for this drought or that flood, since so many other factors also affect the day’s weather.
Stott and NASA’s Gavin Schmidt, at the Goddard Institute of Space Studies in New York, said it is better to think in terms of odds: Warming might double the chances for heat waves, for example. “That is exactly what’s happening,’’ Schmidt said, “a lot more warm extremes and less cold extremes.’’
The World Meteorological Organization pointed out that this summer’s events fit the international scientists’ projections of “more frequent and more intense extreme weather events due to global warming.’’
In fact, in key cases they’re a perfect fit.
The 2007 Intergovernmental Panel report predicted a doubling of disastrous droughts in Russia this century and cited studies foreseeing catastrophic fires in dry years. It also said that Russia would suffer large crop losses.
The government calls it the worst natural disaster in the nation’s history.
A warmer atmosphere can hold and discharge more water. The 2007 report said rains have grown heavier for 40 years over north Pakistan and predicted greater flooding this century in south Asia’s monsoon region.
The Intergovernmental Panel reported in 2007 that rains had increased in northwest China by up to 33 percent since 1961 and that floods nationwide had increased sevenfold since the 1950s. It predicted still more frequent flooding this century.
The international climate panel projected increased US precipitation this century, except for the Southwest, and more extreme rain events causing flooding.