Sensitivity of wind stress formulation to wind-current coupling and sea surface temperature

Morgan Shaner, Florida State University, Center for Ocean-Atmospheric Prediction Studies, Tallahassee, United States, Eric Chassignet, Florida State University, Center for Ocean-Atmospheric Prediction Studies, Tallahassee, FL, United States and Mark A Bourassa, Florida State Univ, Center for Ocean-Atmospheric Prediction Studies, Tallahassee, United States
Abstract:
Furthering our understanding of ocean's role in the water and energy cycle has become increasingly important due to global climate change impacting ocean circulation and the oceans’ impacts on the climate system. Understanding how ocean-atmospheric coupling can change local ocean surface wind stress is essential for modeling wind driven ocean circulation. The curl of the ocean surface wind stress is the main driver of vertical and horizontal motions in the water column and associated transport of properties. Small errors in wind stress are amplified when computing this curl creating the need for improved parameterizations of ocean-atmospheric coupling in the ocean surface wind stress formulation. This work investigates the variability in the ocean surface wind stress due to wind-current coupling and air-sea temperature differences. Differences in ocean surface wind stress and wind stress curl are computed and quantified by altering the bulk wind stress formulation to include wind-current coupling and sea surface temperature data using a combination of high-resolution HYCOM and CFSR data. This helps us develop an understanding of the impact these processes may have in ocean models and determine at what temporal and spatial scales these physical processes become important.