Pressure patterns could portend heat waves

Signals in atmosphere may help scientists forecast temperature hikes 15 to 20 days out

NASA’s Atmospheric Infrared Sounder mapped deviations in surface air temperatures across the country during the July 2011 heat wave. Yellow marks regions with temperatures five degrees above average. Dark red marks regions with temperatures 15 degrees above average.

Atmospheric Infrared Sounder/JPL/NASA/FLICKR

By Ashley Yeager

October 29, 2013 at 11:13 am

High-pressure patterns in the atmosphere could allow scientists to predict U.S. heat waves five to 10 days sooner than is currently possible with traditional methods.

Right now, scientists can forecast a heat wave about 10 days before it hits. Haiyan Teng of the National Center for Atmospheric Research in Boulder, Colo., and colleagues suggest that an atmospheric pattern of five high-pressure systems spanning the Northern Hemisphere could signal a heat wave is on its way in 15 to 20 days.

The team reports the findings, based on a 12,000-year climate simulation, October 27 in Nature Geoscience. Although many scientists think changes in tropical sea surface temperatures or rain from Asian monsoons might be good predictors of heat waves, the authors note that the high-pressure systems identified in this study are probably a result of natural climate variability.