Nuclear Winter Responses to Nuclear War Between the United States and Russia in the Whole Atmosphere Community Climate Model Version 4 and the Goddard Institute for Space Studies ModelE
Current nuclear arsenals used in a war between the United States and Russia could inject 150 Tg of soot from fires ignited by nuclear explosions into the upper troposphere and lower stratosphere. We simulate the climate response using the Community Earth System Model-Whole Atmosphere Community Climate Model version 4 (WACCM4), run at 2 degrees horizontal resolution with 66 layers from the surface to 140 km, with full stratospheric chemistry and with aerosols from the Community Aerosol and Radiation Model for Atmospheres allowing for particle growth. We compare the results to an older simulation conducted in 2007 with the Goddard Institute for Space Studies ModelE run at 4 degrees x 5 degrees horizontal resolution with 23 levels up to 80 km and constant specified aerosol properties and ozone. These are the only two comprehensive climate model simulations of this scenario. Despite having different features and capabilities, both models produce similar results. Nuclear winter, with below freezing temperatures over much of the Northern Hemisphere during summer, occurs because of a reduction of surface solar radiation due to smoke lofted into the stratosphere. WACCM4's more sophisticated aerosol representation removes smoke more quickly, but the magnitude of the climate response is not reduced. In fact, the higher-resolution WACCM4 simulates larger temperature and precipitation reductions than ModelE in the first few years following a 150-Tg soot injection. A strengthening of the northern polar vortex occurs during winter in both simulations in the first year, contributing to above normal, but still below freezing, temperatures in the Arctic and northern Eurasia.
1.Rutgers State Univ, Dept Environm Sci, New Brunswick, NJ 08901 USA 2.Natl Ctr Atmospher Res, Atmospher Chem Observat & Modeling Lab, POB 3000, Boulder, CO 80307 USA 3.Univ Colorado, Atmospher & Space Phys Lab, Campus Box 392, Boulder, CO 80309 USA 4.Univ Colorado, Dept Atmospher & Ocean Sci, Boulder, CO 80309 USA
Recommended Citation:
Coupe, Joshua,Bardeen, Charles G.,Robock, Alan,et al. Nuclear Winter Responses to Nuclear War Between the United States and Russia in the Whole Atmosphere Community Climate Model Version 4 and the Goddard Institute for Space Studies ModelE[J]. JOURNAL OF GEOPHYSICAL RESEARCH-ATMOSPHERES,2019-01-01,124(15):8522-8543