Spatial structure of air-sea interaction in the tropical Atlantic Ocean

The proposed study will investigate the spatial structure of surface fluxes and waves due to organized patterns of low clouds along with ocean mesoscale eddies and fronts. These processes are known to coexist in all tropical oceans, but the details of their spatial variations have not been captured in any available datasets. Waves, trade winds, shallow clouds, and ocean eddies frequently coexist in the tropical northwestern Atlantic, where the ATOMIC field campaign has been planned. We propose an observation-based project as part of ATOMIC, in which we will investigate the spatial structure in the atmospheric and oceanic mixed layers when cloud patterns and ocean mesoscale eddies are present. We will use a distributed array of ten autonomous platforms called SWIFTs, a NOAA research vessel, and the NOAA P3 aircraft to make these observations. The Surface Wave Instrumented Floats with Tracking (SWIFTs) will offer a Lagrangian, distributed view of ocean features as they evolve and clouds as they develop overhead.
The specific scientific questions raised about clouds and waves are:
1. How are surface energy fluxes influenced by organized cloud patterns within the trade winds and spatial gradients in SST across eddies?
2. How are surface waves, and in particular wave breaking, modified by ocean mesoscale variations in currents?
3. How are surface fluxes and turbulence in the oceanic and atmospheric mixed layers impacted by coinciding perturbations of cloud and wave conditions?
1-D air-sea interaction has been well-studied with decades of point-measurements collected from ships. That these measurements only cover a single point in space produces the largest gap in our understanding of air-sea interaction as well as the largest limitation of these datasets for use by numerical models. Research is needed on waves and air-sea fluxes, particularly in the tropics where ocean mesoscale features, persistent trade winds, and organized patterns of low-clouds coexist. The overarching theme of this work is to understand how fine-scale patterns in the oceanic and atmospheric mixed layers co-evolve so that, in the future, these processes can be represented in satellite data and predicted in numerical models with greater fidelity. Our project involves multiple observational datasets in the ocean, atmosphere, and at the sea surface. The project methodology systematically sifts through these data with objective analysis focused on physical processes. These steps will efficiently translate data into research results about coupled air-sea interaction that are actionable and relevant for operational environmental monitoring and numerical prediction.