References

OSD

Ocean Science Discussions

OSD

Ocean Sci. Discuss.

1812-0822

Göttingen, Germany

10.5194/osd-8-1301-2011

Calculating the water and heat balances of the Eastern Mediterranean basin using ocean modelling and available meteorological, hydrological, and ocean data

Shaltout

¹ ³ Omstedt

Department of Oceanography, University of Alexandria, Alexandria, Egypt

Department of Earth Sciences, University of Gothenburg, Göteborg, P.O. Box 460, 40530, Gothenburg, Sweden

currently at: Department of Earth Sciences, University of Gothenburg, Göteborg, P.O. Box 460, 40530, Gothenburg, Sweden

14 06 2011

8 3 1301 1338

2011

This work is licensed under the Creative Commons Attribution 3.0 Unported License. To view a copy of this licence, visit https://creativecommons.org/licenses/by/3.0/

This article is available from https://os.copernicus.org/preprints/8/1301/2011/osd-8-1301-2011.html

The full text article is available as a PDF file from https://os.copernicus.org/preprints/8/1301/2011/osd-8-1301-2011.pdf

This paper analyses the Eastern Mediterranean water and heat balances over a 52-yr period. The modelling uses a process-oriented approach resolving the one-dimensional equations of momentum, heat, and salt conservation, with turbulence modelled using a two-equation model. The exchange through the Sicily Channel connecting the Eastern and Western basins is calculated from satellite altimeter data. The results illustrates that calculated surface temperature and salinity follow the reanalysed data well and with biases of −0.4 °C and −0.004, respectively. Monthly and yearly temperature and salinity cycles are also satisfactory simulated. Reanalysed data and calculated water mass structure and heat balance components are in good agreement, indicating that the air-sea interaction and the turbulent mixing are realistically simulated. The study illustrates that the water balance in the Eastern Mediterranean basin is controlled by the difference between inflows/outflows through the Sicily Channel and by the net precipitation rates. The heat balance is controlled by the heat loss from the water surface, sun radiation into the sea, and heat flow through the Sicily Channel, the first two displaying both climate trends. An annual net heat loss of approximately 9 W m<sup>−2</sup> was balanced by net heat in flow through the Sicily Channel.

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