Constraining Ozone Deposition to Sea and Lake Surfaces 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 relatively few measurements of ozone vertical fluxes over the remote ocean. Here we explore the initial feasibility of calculating ozone vertical fluxes during the four ATom deployments and the AEROMMA project on the NASA DC-8 from data taken on horizontal flight legs at 200 m above the sea surface in the remote Pacific and Atlantic Oceans, the Pacific Ocean near the west coast of the U.S., and Lakes Michigan and Ontario.

We use vertical wind speed, temperature, water vapor, ozone, 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 also calculate water vapor and heat fluxes during these same transects. If successful, this approach could provide 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, and offer novel constraints to global model parameterizations of these processes.