Preprints
https://doi.org/10.5194/egusphere-2023-1724
https://doi.org/10.5194/egusphere-2023-1724
22 Jan 2024
 | 22 Jan 2024

Air-sea interactions in stable atmospheric conditions: Lessons from the desert semi-enclosed Gulf of Eilat (Aqaba)

Shai Abir, Hamish A. McGowan, Yonatan Shaked, Hezi Gildor, Efrat Morin, and Nadav G. Lensky

Abstract. Accurately quantifying air-sea heat and gas exchange is crucial for comprehending thermoregulation processes and modeling ocean dynamics; these models incorporate bulk formulae for air-sea exchange derived in unstable atmospheric conditions. Therefore, their applicability in stable atmospheric conditions, such as desert-enclosed basins in the Gulf of Eilat/Aqaba (coral refugium), Red Sea, and Persian Gulf, is unclear. We present 2-year Eddy Covariance results from the Gulf of Eilat, a natural laboratory for studying air-sea interactions in stable atmospheric conditions which are directly related to ocean dynamics.

The measured mean evaporation, 3.22 m year-1, approximately double than previously estimated by bulk formulae, is exceeding the heat flux provided by radiation. Notably, in arid environments wind speed seasonal trend is compelling maximum evaporation in summer, with minimum winter rate. The higher evaporation rate appears when elevated wind, particularly in the afternoon, coincide with an increase in vapor pressure difference. The bulk formulae approach inability to capture the seasonal (opposite from our measurements) and annual trend of evaporation is linked to errors in quantifying of the atmospheric boundary layer stability parameter.

Most of the year, there is a net cooling effect of surface water (-79 W m-2), primarily through evaporation. The substantial heat deficit is compensated by the advection of heat via northbound currents from the Red Sea, which we indirectly quantify from energy balance considerations. Cold and dry synoptic-scale winds induce extreme heat loss through air-sea fluxes, and are correlated with destabilizing of the water column during winter and initiating vertical water column mixing.

Publisher's note: Copernicus Publications remains neutral with regard to jurisdictional claims made in the text, published maps, institutional affiliations, or any other geographical representation in this preprint. The responsibility to include appropriate place names lies with the authors.
Share

Journal article(s) based on this preprint

28 May 2024
Air–sea interactions in stable atmospheric conditions: lessons from the desert semi-enclosed Gulf of Eilat (Aqaba)
Shai Abir, Hamish A. McGowan, Yonatan Shaked, Hezi Gildor, Efrat Morin, and Nadav G. Lensky
Atmos. Chem. Phys., 24, 6177–6195, https://doi.org/10.5194/acp-24-6177-2024,https://doi.org/10.5194/acp-24-6177-2024, 2024
Short summary
Download

The requested preprint has a corresponding peer-reviewed final revised paper. You are encouraged to refer to the final revised version.

Short summary
Understanding air-sea heat exchange is vital for studying ocean dynamics. Eddy Covariance...
Share