A Mediterranean cold front identification scheme combining wind and thermal criteria

Abstract

The goal of this study is to advance an automated and objective scheme for the identification of cold fronts over the Mediterranean based on wind‐related criteria, MedFTS, by further incorporating thermal criteria, in order to improve the identification of cold fronts on a climatological basis. These thermal criteria are related to cold advection and the thermal front parameter, and their individual or combined contribution is systematically investigated considering different threshold values. For each combination of thermal criteria and/or threshold values, the results are validated with the aid of statistical indices and metrics, and the optimum scheme configuration for the identification of Mediterranean fronts is selected. The advanced version of MedFTS, named MedFTS_DT, having incorporated both dynamic and thermodynamic criteria, is applied and validated for a decade of fronts over the Mediterranean. It was found that the number of erroneously identified cold fronts over Greece was significantly reduced from MedFTS to MedFTS_DT version by almost 40%, as indicated by the statistical metrics. Therefore, the performance of MedFTS_DT is verified to be superior to MedFTS. As a further attempt to investigate the ability of MedFTS_DT to perform adequate climatological analysis in the Mediterranean, the frequency of the cold fronts was calculated over Greece during the period 2007–2016 on a monthly and seasonal basis, demonstrating that the scheme can capture the intra‐annual variations. Finally, the contribution of the cold fronts to the precipitation over the Mediterranean for the same period was investigated, further supporting the scheme's performance.

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