Posted on 08/31/2007 3:57:07 PM PDT by blam
Source: NASA/Goddard Space Flight Center
Date: August 31, 2007
Global Warming Will Bring Violent Storms And Tornadoes, NASA Predicts
Science Daily — NASA scientists have developed a new climate model that indicates that the most violent severe storms and tornadoes may become more common as Earth's climate warms.
Clouds over North America on August 2, 2000, as measured by GOES-11. (Credit: NASA/NOAA)
Previous climate model studies have shown that heavy rainstorms will be more common in a warmer climate, but few global models have attempted to simulate the strength of updrafts in these storms. The model developed at NASA's Goddard Institute for Space Studies by researchers Tony Del Genio, Mao-Sung Yao, and Jeff Jonas is the first to successfully simulate the observed difference in strength between land and ocean storms and is the first to estimate how the strength will change in a warming climate, including "severe thunderstorms" that also occur with significant wind shear and produce damaging winds at the ground.
This information can be derived from the temperatures and humidities predicted by a climate computer model, according to the new study published on August 17 in the American Geophysical Union's Geophysical Research Letters. It predicts that in a warmer climate, stronger and more severe storms can be expected, but with fewer storms overall.
Global computer models represent weather and climate over regions several hundred miles wide. The models do not directly simulate thunderstorms and lightning. Instead, they evaluate when conditions are conducive to the outbreak of storms of varying strengths. This model first was tested against current climate conditions. It was found to represent major known global storm features including the prevalence of lightning over tropical continents such as Africa and, to a lesser extent, the Amazon Basin, and the near absence of lightning in oceanic storms.
The model then was applied to a hypothetical future climate with double the current carbon dioxide level and a surface that is an average of 5 degrees Fahrenheit warmer than the current climate. The study found that continents warm more than oceans and that the altitude at which lightning forms rises to a level where the storms are usually more vigorous.
These effects combine to cause more of the continental storms that form in the warmer climate to resemble the strongest storms we currently experience.
Lightning produced by strong storms often ignites wildfires in dry areas. Researchers have predicted that some regions would have less humid air in a warmer climate and be more prone to wildfires as a result. However, drier conditions produce fewer storms. "These findings may seem to imply that fewer storms in the future will be good news for disastrous western U.S. wildfires," said Tony Del Genio, lead author of the study and a scientist at NASA's Goddard Institute for Space Studies, New York. "But drier conditions near the ground combined with higher lightning flash rates per storm may end up intensifying wildfire damage instead."
The central and eastern areas of the United States are especially prone to severe storms and thunderstorms that arise when strong updrafts combine with horizontal winds that become stronger at higher altitudes. This combination produces damaging horizontal and vertical winds and is a major source of weather-related casualties. In the warmer climate simulation there is a small class of the most extreme storms with both strong updrafts and strong horizontal winds at higher levels that occur more often, and thus the model suggests that the most violent severe storms and tornadoes may become more common with warming.
The prediction of stronger continental storms and more lightning in a warmer climate is a natural consequence of the tendency of land surfaces to warm more than oceans and for the freezing level to rise with warming to an altitude where lightning-producing updrafts are stronger. These features of global warming are common to all models, but this is the first climate model to explore the ramifications of the warming for thunderstorms.
Note: This story has been adapted from a news release issued by NASA/Goddard Space Flight Center.
Ye gods! We’re going to have weather!
So basically nothing will change?
Looks like they changed more than just the foam over at NASA.
No wonder people at NASA are getting drunk these days. Must be alcohol induced, liberal dementia!
Perhaps it was the meteorologists and not the astronauts at NASA who’ve been helping themselves to the spiked Kool-aid
When did NASA assume the charter for weather predicting, emphasis on predictions.
http://www.freerepublic.com/focus/f-news/1888891/posts
NOAA is the weather institute. NASA might be funding some computer modelling such as James Hansen’s famous study.
When they started singing the medias favorite tunes, I guess.
Isn't this the same old news on which they based their predictions of numerous violent hurricanes for the 2006 season.
It was all a great theory... until 2007.
Did they remember to carry the "2" this time?
Actually, until 2006. Their dire predictions failed them last year, and so far, again this year. And, this year, their theories have been shown to be based on bad computer models. So I guess it's been a kind of cumulative faux pas.
You mean the hockey stick hoax? I think they should stick to science of the provable kind.
When scientists refuse to disclose the means, methods and data, you can count on it being a hoax.
Translation: The hurricanes just aren’t reliable enough to prop up the scam.
More bureacratic b.s. from NASA at taxpayers expense. Why isn’t this barn full of nutcases retired to so they can work for the other ‘end of the world’ rabble rouser, the weather channel.
This might well mean we’ll now have mild weather and fewer thunderstorms and tornadoes. Just as predictions were made a couple of years ago that we were in more and more severe hurricanes, we’ve had the two most hurricane free years in recent memory (knock on wood).
/sigh
"Double" the current carbon dioxide levels and "5 degrees warmer"?? In other words, twice as much C02 and ten times the current temperature increase. Who publicized this...Chicken Little?
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