Constraining Ozone Deposition to the Sea Surface Using Airborne Data

Dry deposition to the ocean surface is an important process that modulates global background ozone values in global atmospheric models. Parameterizations of this process are based on laboratory studies and constrained by relatively few measurements of ozone vertical fluxes over the remote ocean. Here we calculate vertical ozone fluxes from 10 Hz data taken on horizontal flight legs at 200 m above the sea surface in the remote Pacific and Atlantic oceans during the Atmospheric Tomography Mission (ATom) deployments aboard the NASA DC-8 aircraft.

We use vertical wind speed, ozone, temperature, water vapor, and other chemical tracer data during low-level legs of the DC-8 aircraft to calculate and qualify ozone vertical fluxes using an eddy covariance analysis. We simultaneously calculate water vapor and heat fluxes during these same transects. This approach provides a spatially extensive assessment of marine boundary layer entrainment rates and dry deposition rates for a variety of chemical species measured at high time resolution in ATom, and offer novel constraints to global model parameterizations of these processes.