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Atmosphere dust represents a mixture of minute particles of various salts and minerals. Also it contains remains of animal and vegetable organisms, spores of causative organisms and so forth. The dust is carried by winds over considerable distances and its presence in the atmosphere is among the factors which have essential influence on the global climate of the Earth. At present the Aeolian processes and their consequences are monitored from space using multispectral optical systems (TOMS, METEOSAT, MODIS etc.) only. These are not capable of reliable identification of the areas themselves that are sources of raising the dust in the atmosphere independently of the cloudiness, solar illumination and transparency of the atmosphere. This problem can be solved with the use of space radar systems of the Earth remote sensing. The paper presents the first results of the development of a radar technique of identification of desert regions in which dust from the surface is transported up into the atmosphere under the action of Aeolian processes. The work was performed using data of Earth remote sensing SAR Envisat-1 obtained over deserts of Mauritania. Specific features of display of the narrow-beam backscattering of radio waves in radar images in dependence on the surface wind speed and direction and direction of radar illumination of the surface. It is concluded that the radar means of remote sensing represent an efficient tool for detecting regions of dust raise into the atmosphere. Results of the study can be used for the development of new methods of remote monitoring of the processes in desert areas that affect the climate of vast regions of the Earth.

Aeolian process of sand and dust transporting is known to form the near-ground surface structures over vast territories and fill the atmosphere up with suspended aerosols-like dust particles which are spread then by winds over long distances. The presence of atmospheric dust in the planet's environment is one of the factors affecting the temperature and climatic conditions of vast regions of the Earth. A number of publications (Ivanov et al., 2015; Ivanov et al., 2016; Ivanov et al., 2016; Ivanov et al., 2018) analyze the revealed effect of anomalously highly(narrow) directed backscattering of radio waves which manifests itself in radar remote sensing (in range of local irradiation angles θ ≈ 31°÷32°) in areas covered with deep sand. At the same time, there is no specific data available from published studies investigating the impact of the near-surface wind on anomalously highly-directional backscattering of radio waves based on the results of radar remote sensing researches of Aeolian sand and dust transport processes in desert regions that, in turn, could have been used later to determine the parameters of such transport process. This article presents the results of analysis of the data obtained from long-term studies of desert regions of El-Djuf, Akshar and Trarza in Mauritania by means of space-borne SAR Envisat-1. The purpose of the analysis was actually to identify the specifics of the effect that the near-surface wind has on the anomalously highly-directional backscattering of radio waves which is identified by radar based researches of Aeolian processes of sand and dust transport in desert regions, so can be used for remote determination of such transportation parameters.

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