This is significant. Bear-in mind-if increasing SSTs (sea-surface temps) in the tropics bring more clouds/rain in general (a very distinct probability), such an upward trend in DCC storm frequency/intensity could be aborted-or (perhaps more likely) become cyclic. Either way-be ready for Katrina & Rita’s siblings…
ASW
GEOPHYSICAL RESEARCH LETTERS
VOL. 35, L19805, doi:10.1029/2008GL034562, 2008
Frequency of severe storms and global warming
Hartmut H. Aumann et al
Abstract
We use five years of data from the Atmospheric Infrared Sounder
(AIRS) to develop a correlation between the frequency of Deep
Convective Clouds (DCC) and the zonal mean tropical surface
temperature. AIRS data show that the frequency of DCC in the tropical
oceans is very temperature sensitive, increasing 45% per 1 K increase
of the zonal mean surface temperature. The combination of the
sensitivity of the DCC frequency to temperature indicates that the
frequency of DCC, and as a consequence the frequency of severe
storms, increases at the rate of 6%/decade with the current +0.13
K/decade rate of global warming. This result is only qualitatively
consistent with state-of-the-art climate models, where the frequency
of the most intense rain events increases with global warming.
Received 2 May 2008; accepted 18 August 2008; published 3 October 2008.
Keywords: Deep Convective Clouds; AIRS; atmospheric sounding;
hyper-spectral; infrared.
Index Terms: 1610 Global Change: Atmosphere (0315, 0325); 1616 Global
Change: Climate variability (1635, 3305, 3309, 4215, 4513); 3314
Atmospheric Processes: Convective processes; 1817 Hydrology: Extreme
events; 3362 Atmospheric Processes: Stratosphere/troposphere
interactions.
—————————————————————————————————————-