|Title||Air-sea fluxes with a focus on heat and momentum|
|Publication Type||Journal Article|
|Year of Publication||2019|
|Authors||Cronin MF, Gentemann C.L, Edson J., Ueki I., Bourassa M., Brown S., Clayson CA, Fairall CW, Farrar J.T, Gille ST, Gulev S., Josey S.A, Kato S., Katsumata M., Kent E., Krug M., Minnett P.J, Parfitt R., Pinker RT, Stackhouse P.W, Swart S., Tomita H., Vandemark D., Aweller R., Yoneyama K., Yu L., Zhang D.X|
|Type of Article||Review|
|Keywords||air-sea heat flux; autonomous surface vehicle; bulk parameterization; Environmental Sciences & Ecology; gulf-stream; ICOADS; intraseasonal variability; Kuroshio Extension; latent heat flux; Marine & Freshwater Biology; ocean monitoring system; ocean surface albedo; ocean wind; OceanSITES; part i; profile relationships; retrieval; satellite-based; stress; surface radiation; temperature; western pacific; wind stress|
Turbulent and radiative exchanges of heat between the ocean and atmosphere (hereafter heat fluxes), ocean surface wind stress, and state variables used to estimate them, are Essential Ocean Variables (EOVs) and Essential Climate Variables (ECVs) influencing weather and climate. This paper describes an observational strategy for producing 3-hourly, 25-km (and an aspirational goal of hourly at 10-km) heat flux and wind stress fields over the global, ice-free ocean with breakthrough 1-day random uncertainty of 15 W m(-2) and a bias of less than 5 W m(-2). At present this accuracy target is met only for OceanSITES reference station moorings and research vessels (RVs) that follow best practices. To meet these targets globally, in the next decade, satellite-based observations must be optimized for boundary layer measurements of air temperature, humidity, sea surface temperature, and ocean wind stress. In order to tune and validate these satellite measurements, a complementary global in situ flux array, built around an expanded OceanSITES network of time series reference station moorings, is also needed. The array would include 500-1000 measurement platforms, including autonomous surface vehicles, moored and drifting buoys, RVs, the existing OceanSITES network of 22 flux sites, and new OceanSITES expanded in 19 key regions. This array would be globally distributed, with 1-3 measurement platforms in each nominal 10 degrees by 10 degrees box. These improved moisture and temperature profiles and surface data, if assimilated into Numerical Weather Prediction (NWP) models, would lead to better representation of cloud formation processes, improving state variables and surface radiative and turbulent fluxes from these models. The in situ flux array provides globally distributed measurements and metrics for satellite algorithm development, product validation, and for improving satellite-based, NWP and blended flux products. In addition, some of these flux platforms will also measure direct turbulent fluxes, which can be used to improve algorithms for computation of air-sea exchange of heat and momentum in flux products and models. With these improved air-sea fluxes, the ocean's influence on the atmosphere will be better quantified and lead to improved long-term weather forecasts, seasonal-interannual-decadal climate predictions, and regional climate projections.