The short-term effect on carbonate parameters from hurricanes Harvey, Irma, and Maria.

Tropical storms and hurricanes are events with potentially extreme impacts on ocean conditions. Strong winds generating vigorous vertical mixing and extensive precipitation affect both temperature and salinity in the mixed layer. The surface temperature, for example, decreased several degrees C in the wake of both hurricanes Irma and Maria. While it is clear that the physical state of the surface ocean is affected by hurricanes, how such storms affect carbonate system variability is still an open question. Changes in temperature and salinity combined with extreme winds create the potential for changes in solubility of pCO2, and large net fluxes of CO2 across the air-sea interface. A deepening of the mixed layer from wind-driven mixing may further affect the carbonate system, as sub-surface waters rich in dissolved inorganic carbon and nutrients are entrained to the surface. To examine these process, we evaluate simulated fields of temperature and salinity (from a 1/12° global data assimilated General Circulation Model), satellite ocean color and wind speed data within the context of a conceptual box model. Our model is compared to observed pCO2, wind speed, temperature and salinity data from buoyed assets that survived the storms. We address total CO2 fluxes, the relative effects temperature, salinity and biology on the carbonate system, and the time scales over which the system is "restored" to its initial state. We explore the connection between the magnitude of perturbation and the length of time it takes for the system to recover, and observe recovery over time scales lasting from days to weeks depending on the storm. Although not observed in these data, we speculate that depending on the buoyancy frequency, recovery elsewhere could take place over monthly time scales, raising the potential that hurricanes could exacerbate or alleviate environmental stresses on calcifying marine organisms.