Air-Sea Surface Fluxes over Ocean Eddies during the Atlantic Tradewind Ocean-Atmosphere Mesoscale Interaction Campaign (ATOMIC)

In the region of the northwest tropical Atlantic, there are energetic ocean eddies. They are anticyclonic warm core eddies and cyclonic cold core eddies generated in the interior ocean propagating to the western boundary, and deep reaching North Brazil Current (NBC) Rings generated by the NBC retroflection. These eddies can have strong signatures in sea surface temperature (SST) and surface currents, and thus modulate surface latent and sensible heat fluxes and momentum flux. Possible roles of these eddies on air-sea coupling and atmospheric shallow clouds in the region are unknown.
In January-February 2020, U.S. and European scientists will jointly conduct field observations of Atlantic Tradewind Ocean-Atmosphere Mesoscale Interaction Campaign (ATOMIC) and EUREC4A-OA (Elucidating the role of clouds-circulation coupling in climate – Ocean and Atmosphere) in the northwest tropical Atlantic east of Barbados. The goal is to understand the air-sea interaction in the region, focusing on mesoscale ocean eddies and their influences on atmospheric shallow convection and formation of shallow cumulus clouds. This proposed research is to participate in this field campaign by deploying two Saildrones that cover the campaign period and beyond for 180 days.
The objective of the Saildrone deployment is to advance understanding of air-sea coupling associated with ocean eddies in this region through measuring their signals in SST, SSS, upper-ocean current profiles, surface air temperature, humidity, pressure, wind direction and speed, short- and long-wave radiation, and possibly cloud images. These Saildrone measurements will complement in situ measurements to be made by ships, aircraft and other autonomous devices and remote measurement by satellites during the field campaign. The advantage of the Saildrones is their controllable mobility and long duration, which would allow them to be steered to follow individual ocean eddies and to sample a large number of eddies.
The proposed Saildrone deployment during the ATOMIC-EUREC4A-OA campaign directly responds to the CVP solicitation for proposals that focuses on observing, understanding, and/or process modeling of upper ocean processes and air-sea interactions in the Northwest Tropical Atlantic. The proposed effort directly contributes to the first two objectives of NOAA’s long-term climate goals as described in NOAA’s Next-Generation Strategic Plan (NGSP): 1) Improved scientific understanding of the changing climate system and its impacts; 2) Assessment of current and future states of the climate system that identify potential impacts and inform science, service, and stewardship decisions.