RADAR TECHNIQUES FOR IDENTIFICATION OF DESERT REGIONS – THE SOURCES OF DUST IN THE ATMOSPHERE

Abstract

Atmospheric dust is a mixture of minute particles of various salts and minerals; it also contains the remains of plants and animals, spores of pathogenic microbes, etc. The winds carry the dust over long distances, and its presence in the atmosphere is one of the factors that significantly affect the planet's climate. Currently, for space monitoring of aeolian processes and their consequences only multispectral optical systems are used (TOMS, METEOSAT, MODIS, etc.); they cannot identify the areas which are the sources of raising dust in the atmosphere regardless of clouds, brightness and transparency of the atmosphere. This problem can be solved by the space remote sensing radar systems. The article presents the first results of processing the method of radar identification of desert areas in which under the influence of aeolian processes the process of raising dust from the surface to the atmosphere takes place. The testing was performed using the data of radar remote sensing of Mauritania deserts of SAR Envisat-1. The peculiarities of manifestation of focused backscattering of radio waves in radar images at different speeds of surface wind, surface radar radiation and wind directions were analyzed. It is concluded that applying the radar remote sensing to identify areas raising dust in the atmosphere is effective. The results of the study allow to create new methods of remote monitoring of processes in desert areas, affecting the climate of vast regions of the Earth.

Keywords

• aeolian transport of sand and dust
• electric field
• highly directional radio wave backscatter
• ionization
• radar sensing
• sand ripples