The global pandemic of covid-19 is, in its way, a triumph for the scientific method: scientists warned for a long time of the danger of a pandemic caused by a novel virus and so it has come to pass.
But in the crisis we shouldn’t forget all the other issues science warns us about – and here’s something else to cheer you up: even a ‘limited’ nuclear war in (for Europeans and Americans) far off parts of the world could cause a decade of starvation.
The concept of a nuclear winter isn’t a new one – and if you’ve ever watched Threads you are unlikely to be under any illusions about just how devastating the climate collapse that would follow a full-scale nuclear exchange would be.
But even a ‘limited’ nuclear exchange between India and Pakistan – two countries which have engaged in full-scale war three times in 80 years and where incidents of military conflict are frequent – would be devastating to global food supplies according to a new study published in the Proceedings of the National Academy of Sciences in the US.
“A regional nuclear conflict would compromise global food security” is based on a scenario of 100 15 kilotonne strikes (i.e. similar in yield and numbers if two British Vanguard class submarines fired off all their missiles). They estimate that the soot from the fires created would lower the global temperature by 1.8 celsius and that this would do much more damage than a 1.8 degree warming caused by carbon dioxide, because the carbon dioxide would also encourage growth.
Their abstract reads:
A limited nuclear war between India and Pakistan could ignite fires large enough to emit more than 5 Tg of soot into the stratosphere. Climate model simulations have shown severe resulting climate perturbations with declines in global mean temperature by 1.8 °C and precipitation by 8%, for at least 5 y. Here we evaluate impacts for the global food system. Six harmonized state-of-the-art crop models show that global caloric production from maize, wheat, rice, and soybean falls by 13 (±1)%, 11 (±8)%, 3 (±5)%, and 17 (±2)% over 5 y. Total single-year losses of 12 (±4)% quadruple the largest observed historical anomaly and exceed impacts caused by historic droughts and volcanic eruptions. Colder temperatures drive losses more than changes in precipitation and solar radiation, leading to strongest impacts in temperate regions poleward of 30°N, including the United States, Europe, and China for 10 to 15 y. Integrated food trade network analyses show that domestic reserves and global trade can largely buffer the production anomaly in the first year. Persistent multiyear losses, however, would constrain domestic food availability and propagate to the Global South, especially to food-insecure countries. By year 5, maize and wheat availability would decrease by 13% globally and by more than 20% in 71 countries with a cumulative population of 1.3 billion people. In view of increasing instability in South Asia, this study shows that a regional conflict using <1% of the worldwide nuclear arsenal could have adverse consequences for global food security unmatched in modern history.
The impact would be global:
Why bring it up now, just as we are facing another crisis of deep and lasting significance? Because nothing breeds conflict more than internal stress in a state. The impact of covid-19 on India or Pakistan will certainly not be positive and if it pushes either state towards conflict that matters for all of us.
More than that, the pandemic should be the opportunity to drum home the point that we need to solve conflicts and problems, not just hope they will go away if we ignore them.