A diagnostic study of winter diabatic heating in the Mediterranean in relation to cyclones

Authors

  • Y. Shay-El,

    1. Raymond and Beverly Sackler Faculty of Exact Sciences, Department of Geophysics and Planetary Sciences, Tel Aviv University, Ramat Aviv 69978, Israel
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  • P. Alpert

    1. Raymond and Beverly Sackler Faculty of Exact Sciences, Department of Geophysics and Planetary Sciences, Tel Aviv University, Ramat Aviv 69978, Israel
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Abstract

Diabatic heating and net condensation rates during winter are calculated over the Mediterranean and surrounding areas from the 1982-88 ECMWF initialized analyses using the residual method for the heat and moisture budgets. The steady-state contributions over the Mediterranean are found to be prominent as in the tropics, but contrary to the case of the tropics the transients contributions in the Mediterranean, attributed to cyclonic activity, are not at all negligible.

A composite Cyprus low was constituted from 67 typical cyclones in the eastern Mediterranean. The diabatic heating and net condensation distribution indicate vigorous sea fluxes especially in the lee of the Turkish mountains over the Aegean Sea where the air-sea contrast is maximized. In contrast with other regions, the maximum in the vertical profile of diabatic heating due to latent heat release is found at a lower altitude of about 850 hPa. It is suggested that this fact has important implications in modelling Mediterranean cyclones.

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