Decadal reduction of Chinese agriculture after a regional nuclear war

A regional nuclear war between India and Pakistan could decrease global surface temperature by 1∘C–2∘C for 5–10 years and have major impacts on precipitation and solar radiation reaching Earth’s surface. Using a crop simulation model forced by three global climate model simulations, we investigate the impacts on agricultural production in China, the largest grain producer in the world. In the first year after the regional nuclear war, a cooler, drier, and darker environment would reduce annual rice production by 30 megaton (Mt) (29%), maize production by 36Mt (20%), and wheat production by 23Mt (53%). With different agriculture management—no irrigation, auto irrigation, 200 kg/ha nitrogen fertilizer, and 10 days delayed planting date—simulated national crop production reduces 16%–26% for rice, 9%–20% for maize, and 32%–43% for wheat during 5 years after the nuclear war event. This reduction of food availability would continue, with gradually decreasing amplitude, for more than a decade. Assuming these impacts are indicative of those in other major grain producers, a nuclear war using much less than 1% of the current global arsenal could produce a global food crisis and put a billion people at risk of famine.