Anomalous Microwave Propagation Assessment in the Lower Troposphere Using a Bulk Meteorological Parameter

摘要

In their 1967 study 'On the Influence of the Meteorological Conditions on the Radiation Properties of Long Range Radars and on the Field Strength From a Distant Radio Transmitter,' Gjessing and Moene (G&M) developed a procedure which uses a delta N parameter evaluated at the 850 mb level to assess the propagation properties for microwave transmissions. This present study examines the skill of the G&M procedure to determine resulting accuracy, optimum value of delta N, and preferred vertical region of assessment. EASTPAC radiosonde soundings are used to determine the refractive structure in the given vertical region, and to calculate the value of delta N (850 mb). The G&M procedure's skill is found to be comparable to, or in some cases better than, the skill of present day weather forecasts. The G&M procedure is found to have skill in assessing the existence of anomalous propagation between the surface and the 850 mb level with no indication to the vertical location within this region. The optimum value of delta N is found to be similar to that used by Gjessing and Moene. (Author)