Articles | Volume 21, issue 4
https://doi.org/10.5194/os-21-1641-2025
© Author(s) 2025. This work is distributed under
the Creative Commons Attribution 4.0 License.
the Creative Commons Attribution 4.0 License.
https://doi.org/10.5194/os-21-1641-2025
© Author(s) 2025. This work is distributed under
the Creative Commons Attribution 4.0 License.
the Creative Commons Attribution 4.0 License.
Statistical analysis of ocean currents in the eastern Mediterranean
Department of Environmental Physics, BIDR, Ben-Gurion University of the Negev, Midreshet Ben-Gurion, Israel
Hezi Gildor
The Institute of Earth Sciences, The Hebrew University of Jerusalem, Jerusalem, Israel
Aviv Solodoch
The Institute of Earth Sciences, The Hebrew University of Jerusalem, Jerusalem, Israel
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This preprint is open for discussion and under review for Weather and Climate Dynamics (WCD).
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Severe warming and drying in the Eastern Mediterranean makes seasonal prediction of regional rain imperative. The study explores the observed relation of Mediterranean Sea variability to Levant winter precipitation. Ocean heat uptake in the Aegean Sea during summer is found to be a strong predictor of winter Levant precipitation. This connection is mediated by changes in the subtropical jet, which create more favorable conditions for precipitating storms in the Levant during winter.
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This preprint is open for discussion and under review for Ocean Science (OS).
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The paper examines the applicability of known linear wave theories to numerical simulations of two zonally invariant fundamental problems in Oceanography: The Geostrophic adjustment problem and the Ekman Adjustment problem. By simulating the problems with MITgcm we show that neither of the available wave theories is applicable to the explanation of the numerical results that are derived for large and small meridional domains.
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This paper outlines the process of creating an open-access surface wave dataset, drawing from deep-sea research station observations located 50 km off the coast of Israel. The discussion covers the wave monitoring procedure, from instrument configuration to wave field retrieval, and aspects of quality assurance. The dataset presented spans over 5 years, offering uncommon in situ wave measurements in the deep sea, and addresses the existing gap in wave information within the region.
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Understanding air–sea heat exchange is vital for studying ocean dynamics. Eddy covariance measurements over the Gulf of Eilat revealed a 3.22 m yr-1 evaporation rate, which is inconsistent with bulk formulae estimations in stable atmospheric conditions, requiring bulk formulae to be revisited in these environments. The surface fluxes have a net cooling effect on the gulf water on an annual mean (-79 W m-2), balanced by a strong exchange flux between the Red Sea and the Gulf of Eilat.
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Ocean Sci., 19, 1163–1181, https://doi.org/10.5194/os-19-1163-2023, https://doi.org/10.5194/os-19-1163-2023, 2023
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The transition from an arbitrary initial sea surface height to a geostrophic balance in which the velocity is steady was solved last century for constant Coriolis frequency, f(y), where y is the latitude. This study extends the theory to the realistic case in which f(y) is linear with y. We find that the variation in f(y) translates the steady geostrophic state westward as low-frequency Rossby waves that are harmonic in narrow domains and trapped near the equatorward boundary in wide ones.
Kaushal Gianchandani, Hezi Gildor, and Nathan Paldor
Ocean Sci., 17, 351–363, https://doi.org/10.5194/os-17-351-2021, https://doi.org/10.5194/os-17-351-2021, 2021
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The classical theories of the western boundary currents, proposed in the first half of the 20th century, are extended to include cases of zonally elongated and meridionally narrow ocean basins. Results show for the first time that in basins that are sufficiently narrow meridionally, the equatorward wind-driven transport away from the western boundary is lower than that in meridionally wide basins. Our theoretical results are employed to explain the low transport in the East Australian Current.
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Short summary
We studied ocean currents in the eastern Mediterranean near Israel's coast (2016–2024) across depths of up to 1.3 km. The generalized gamma distribution best matched current-speed data. The speed increment time series fit a stretched exponential distribution better than a normal distribution. Comparisons with high-resolution and regional general circulation models showed discrepancies, highlighting the need to refine the models for better extreme current-speed event predictions.
We studied ocean currents in the eastern Mediterranean near Israel's coast (2016–2024) across...