Coupled physical-biogeochemical modeling investigation on the upper ocean physical and biogeochemical responses to passages of 46 major hurricanes in the Northwest Atlantic Ocean: A historical synthesis

Hurricane-driven ocean upwelling brings colder, nutrient-rich and carbon-rich deep water to the upper ocean column, significantly influencing ocean surface physical and biogeochemical properties. At the same time, strong wind speed and mixing associated with each hurricane also introduce strong gas transport rate, and air-sea CO₂ flux. To quantify the upper ocean physical and biogeochemical response to passages of major Atlantic hurricanes, a coupled physical-biogeochemical modeling system was developed and applied to simulate the northwest Atlantic ocean responses to 46 historical hurricanes during 2007-2017. Impacts of these hurricanes on sea surface temperature, nitrate, dissolved inorganic carbon (DIC), water pCO₂, and air-sea CO₂ flux were statistically evaluated and synthesized. Our results show that both SST and surface water pCO₂ decreased during passages of all hurricanes due to upwelling processes. The responses of nitrate, DIC and CO₂ flux however are much more complex, and they are related closely to intrinsic storm characteristics including strom’s spatial range, translation speed, and intensity.