8°c Sunny
Winnipeg Free Press - PRINT EDITION
Warmer winter? Thank Tokyo
Heat from big cities may warm Manitoba
WASHINGTON -- Heat rising up from cities such as New York, Paris and Tokyo might be remotely warming up winters as far away as Manitoba, North Dakota and Alaska, a surprising study theorizes.
In an unusual twist, that same urban heat from buildings and cars may be slightly cooling the autumns in much of the Western United States, Eastern Europe and the Mediterranean, according to the study published Sunday in the scientific journal Nature Climate Change.
Meteorologists have long known cities are warmer than rural areas, with the heat of buildings and cars, along with asphalt and roofs that absorb heat. That's called the urban heat island effect, and it's long been thought the heat stayed close to the cities.
But the study, based on a computer model and the Northern Hemisphere, now suggests the heat does something else, albeit indirectly. It travels about 800 metres up into the air and then its energy changes the high-altitude currents in the atmosphere that dictate prevailing weather.
"Basically, it changes the flow," said Guang Zhang of the Scripps Institution of Oceanography in La Jolla, Calif. He wrote the paper with Aixue Hu at the National Center for Atmospheric Research in Boulder, Colo.
This doesn't change overall global temperature averages significantly, unlike man-made greenhouse gases that cause global warming. Instead, it redistributes some of the heat, the scientists said.
The changes seem to vary with the seasons and by region because of the way air currents flow at different times of the year. During the winter, the jet stream is altered and weakened, keeping cold air closer to the Arctic Circle and from dipping down as sharply, Hu explained.
The computer model showed parts of Siberia and northwestern Canada may get, on average, an extra 0.8 to one degree Celsius during the winter, which "may not be a bad thing," Zhang said. The effect isn't quite as much in Manitoba and northern North Dakota, where temperatures might be about half a degree warmer (0.3 C).
In contrast, Europe and the Pacific Northwest are cooled slightly in the winter from this effect. The jet-stream changes prevent weather systems from bringing warmer air from the Atlantic to Europe and from the Pacific to the U.S. Northwest, thus cooling those areas a bit, he said.
The biggest cooling occurs in the fall, but Hu said he's not quite sure why that happens.
Several outside scientists said they were surprised by the study results, calling the work "intriguing" and "clever." But they said it would have to be shown in more than one computer model and in repeated experiments before they could accept this theory.
-- The Associated Press
Republished from the Winnipeg Free Press print edition January 28, 2013 A7
More World
- Back to Top
- Return to World
More World
(1 of 20 articles for today)
At Cannes Film Festival, Jerry Lewis still not laughing at female comedians
9:35 AM 0
Poll
Most Popular World
- Brave woman tried to calm London attackers and reasoned with them before police came
- Man shot to death in Fla. while being questioned in Boston Marathon bombing investigation
- British official: Suspects in butchering of soldier had been part of previous investigations
- Youths in Stockholm burn down restaurant, torch more than 30 cars in 4th night of rioting
- Gay teen charged for having younger girlfriend
- Preliminary estimate puts Oklahoma tornado damage at $2 billion; 13,000 homes damaged, ruined
- Polish man gets quick face transplant in what doctors say was life-saving decision
- 'An eye for an eye'
- Canseco accused of sex assault in Vegas; former slugger airs info on Twitter
- The pope and the devil: Francis' obsession with Satan leads to suspicion he performed exorcism
- Massive tornado roars through Oklahoma City suburb, killing at least 51
- Search for survivors of Oklahoma tornado nearly complete, as homeowners confront devastation
- Man shot to death in Fla. while being questioned in Boston Marathon bombing investigation
- Phone cracked? Cool
- US woman credits 'mother's instincts' in chase of 4-year-old daughter's abductor
- Polish man gets quick face transplant in what doctors say was life-saving decision
- Umbrella-gate stirs outrage
- Brave woman tried to calm London attackers and reasoned with them before police came
- US zoo looking into conception mystery after birth of anteater; no male in pen
- Remote Alaska volcano continues to erupt, with lava fountains, ash plumes
- Amanda Berry, 1 of 3 women freed after held captive in Ohio home, arrives at sister's home
- Massive tornado roars through Oklahoma City suburb, killing at least 51
- Friendship with bomb suspect, complex chain of events leads to 3 being charged
- Police vow to solve shooting that wounded 19 people during Mother's Day parade in New Orleans
- Missing Pa. woman, last seen dropping off kids for school in 2002, surfaces in Fla.
- Cleveland police: Ohio captive suffered 5 miscarriages after being beaten and starved
- Jodi Arias convicted of first-degree murder, says she prefers death penalty
- Neighbours: Man in custody comforted missing girl's mom, helped search for missing US women
- Search for survivors of Oklahoma tornado nearly complete, as homeowners confront devastation
- High school baseball team lifts car to free 16-year-old girl
- Phone cracked? Cool
- Ray Manzarek, keyboardist and founding member of rock group The Doors, dies at 74 from cancer
- Hatchet-wielding hitchhiker who intervened in California attack arrested in NJ homicide
- Remote Alaska volcano continues to erupt, with lava fountains, ash plumes
- Argentina's 'dirty war' dictator dies
- Massive tornado roars through Oklahoma City suburb, killing at least 51
- Shady characters: Cookie Monster, Elmo accused of aggressive behaviour in Times Square
- U.S. envoy punted; Russia alleges spying
- US woman credits 'mother's instincts' in chase of 4-year-old daughter's abductor
- Up to 60 people injured when car drives into Va. parade; medical emergency possible cause
- 'Coronation Street' actor William Roache charged in UK over alleged rapes in 1967
- Coroner: 5-year-old boy shoots 2-year-old sister in US with rifle he got as a gift
- Hitler ate well, his food taster recalls
- Black bear wanders into LA-area suburbia, chases swimmers from pool, strands kids in class
- Female guards, rapidly growing in numbers, at heart of U.S. prison scandal
- Phone cracked? Cool
- Bill to alter rules of succession before Kate gives birth nears completion as Lords approve
- US tourists swim for nearly 14 hours after boat sinks near St. Lucia
- IBM makes movie about a little boy - a very little boy - by pushing molecules around
- Friendship with bomb suspect, complex chain of events leads to 3 being charged
Ads by Google
You can comment on most stories on winnipegfreepress.com. You can also agree or disagree with other comments. All you need to do is register and/or login and you can join the conversation and give your feedback.
Have Your Say
New to commenting? Check out our Frequently Asked Questions.
The Winnipeg Free Press does not necessarily endorse any of the views posted. By submitting your comment, you agree to our Terms and Conditions. These terms were revised effective April 16, 2010.