Heat rising from large cities might be warming winters in far-away rural areas, according to a Scripps Institution of Oceanography and National Center for Atmospheric Research study. Meteorologists have long known that cities are warmer than rural areas because buildings, cars, asphalt and roofs absorb heat. It was previously thought that the heat stayed close to cities.
The study, which is based on a computer model and studies the Northern Hemisphere, now suggests that city heat travels about half a mile up into the air, changing the high-altitude currents in the atmosphere that dictate prevailing weather, Seth Borenstein of The Associated Press reports. Changes seems to vary with seasons and by region because of the way air currents flow at different times of the year, researchers note in the study, published in the journal Nature Climate Change. They also suggest that this doesn't change overall climate significantly. It just redistributes some of the heat generated in cities. (Read more)
The study, which is based on a computer model and studies the Northern Hemisphere, now suggests that city heat travels about half a mile up into the air, changing the high-altitude currents in the atmosphere that dictate prevailing weather, Seth Borenstein of The Associated Press reports. Changes seems to vary with seasons and by region because of the way air currents flow at different times of the year, researchers note in the study, published in the journal Nature Climate Change. They also suggest that this doesn't change overall climate significantly. It just redistributes some of the heat generated in cities. (Read more)
"They also suggest that this doesn't change overall climate significantly. It just redistributes some of the heat generated in cities."
ReplyDeleteIt's called the urban heat island effect, and it helps explain why most of the averaged warming is due to higher nighttime temps. The study suggests that warming is an artifact of thermometer siting.