Assessing evaporation duct variability in the Eastern Mediterranean Sea in support of radar and radio communications

Abstract

Electro-magnetic (EM) propagation is greatly affected by atmospheric conditions. Although this subject has been an active area of research, a comprehensive evaporation ducting study for the Eastern Mediterranean Sea does not exist. The main objective of this thesis is to make detailed analyses of evaporation ducts in the Eastern Mediterranean Sea in support of Navy and civilian activities in the region. In this thesis, the European Center for Medium-Range Weather Forecasts (ECMWF) surface reanalysis data from 1990 to 2015 are used. The Coupled Ocean-Atmosphere Response Experiment (COARE) bulk surface flux algorithm is modified to output vertical profiles of temperature and humidity with input from the ECMWF reanalysis data. The vertical profiles are then used to derive the associated evaporation duct height (EDH) and evaporation duct strength (EDS). The temporal and spatial variations of EDH and EDS are analyzed to provide an evaporation ducting climatology for the Eastern Mediterranean Sea. The sensitivity of EDH and EDS to certain atmospheric factors is further analyzed to develop a more comprehensive understanding of atmospheric effects on EM propagation. The results show that EDHs are highest in summer, between 12 and 15 UTC (coordinated universal time), and EDHs are greatest in the Aegean Sea.