RADAR INVESTIGATIONS OF THE AEOLIAN SAND AND DUST TRANSPORTING MANIFESTATIONS IN DESERT AREAS

Abstract

Aeolian processes transporting sand and dust is a powerful erosive force that shapes the structure of the surface of the vast territories and loads the atmosphere with aerosols suspended dust spread by wind over long distances. The presence of atmospheric dust in the environment of the planet is one of the factors significantly affecting the temperature and climatic conditions of vast regions. There are no published data on the characteristics of the radio waves scattering features manifested in radar studies of aeolian sand and dust transport processes in desert regions, which can be used for determining the parameters of a remote transport. The article presents the results of the analysis of multiyear surveys of desert areas by side-looking radars (SLR) of “Cosmos-1500” and “Sich-1” satellites, synthetic aperture radars (SAR) of ERS-1, ERS-2 and Envisat-1, aimed at identifying the radio waves scattering features manifested in radar studies of aeolian sand and dust transportation processes in desert regions, which can be used for remote determining the parameters of transportation. It was proposed to explain the mechanism of the effect of a highly directional intense radio waves backscatter, which manifests itself in areas covered with deep sand at the direction of irradiating the surface towards the general direction of the surface wind in the range of local irradiation angle surface Q » 31¸34°, due to their interaction with consistently oriented ionized air layers bordering on sand ripples structures in the process of forming it with aeolian transportation of sand-dust mixture. Ionization is caused by strong inhomogeneous electric field arising in the aeolian transport process. Results of the study allow to create new remote monitoring methods of processes in desert areas that affect the climate of vast regions of the Earth.

Keywords

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