The Potential Impact of Nuclear Conflict on Ocean Acidification

We demonstrate that the global cooling resulting from a range of nuclear conflict scenarios would temporarily increase the pH in the surface ocean by up to 0.06 units over a 5-year period, briefly alleviating the decline in pH associated with ocean acidification. Conversely, the global cooling dissolves atmospheric carbon into the upper ocean, driving a 0.1 to 0.3 unit decrease in the aragonite saturation state (Ωarag) that persists for ~ 10 years. The peak anomaly in pH occurs 2 years post conflict, while the Ωarag anomaly peaks 4- to 5-years post conflict. The decrease in Ωarag would exacerbate a primary threat of ocean acidification: the inability of marine calcifying organisms to maintain their shells/skeletons in a corrosive environment. Our results are based on sensitivity simulations conducted with a state-of-the-art Earth system model integrated under various black carbon (soot) external forcings. Our findings suggest that regional nuclear conflict may have ramifications for global ocean acidification.