Climatological Variability of Microwave Ducting in the Southern California Region

The Department of Defense (DOD) utilizes electromagnetic (EM) waves for communication, radar detection, and weapon guidance systems. It is hence crucial to understand the regional climatological characteristics of the atmosphere that significantly impact EM signal propagation. There are two major objectives of this thesis work. One is to evaluate the European Centre for Medium-Range Weather Forecasts (ECMWF) latest reanalysis product, the ECMWF Re-Analysis V5 (ERA5) dataset for identifying trapping conditions in the coastal marine environment. The other is to examine the climatology of ducting conditions in the southern California bights using the ERA5 data. To accomplish the first objective, we used the ERA5 measurements near the Sea Range at Point Mugu during a past field campaign. We then analyzed nine years of the ERA5 data in the Point Mugu area to determine any climatological differences in the trapping conditions between the years. We found that the ERA5 approximates well trapping conditions in the southern California bights area and discovered seasonal trends of the ducting characteristics as well as their spatial variations.