Climate change. Projected increase in lightning strikes in the United States due to global warming.
Lightning plays an important role in atmospheric chemistry and in the initiation of wildfires, but the impact of global warming on lightning rates is poorly constrained. Here we propose that the lightning flash rate is proportional to the convective available potential energy (CAPE) times the precipitation rate. Using observations, the product of CAPE and precipitation explains 77% of the variance in the time series of total cloud-to-ground lightning flashes over the contiguous United States (CONUS). Storms convert CAPE times precipitated water mass to discharged lightning energy with an efficiency of 1%. When this proxy is applied to 11 climate models, CONUS lightning strikes are predicted to increase 12 ± 5% per degree Celsius of global warming and about 50% over this century.
Department of Earth and Planetary Science, University of California, Berkeley, and Earth Sciences Division, Lawrence Berkeley National Laboratory, Berkeley, CA, USA. romps@berkeley.edu.
David M
DM
Romps
Department of Earth and Planetary Science, University of California, Berkeley, and Earth Sciences Division, Lawrence Berkeley National Laboratory, Berkeley, CA, USA.
Jacob T
JT
Seeley
Department of Atmospheric and Environmental Sciences, State University of New York at Albany, Albany, NY, USA.
David
D
Vollaro
Department of Atmospheric and Environmental Sciences, State University of New York at Albany, Albany, NY, USA.
John
J
Molinari
D018481:Convection; D057232:Global Warming; D008030:Lightning; D014481:United States