Influence of Atmospheric Pressure Surges on the Level of Suprapermafrost Waters and the Flow of Small Rivers (Anadyr Lowland, Chukotka)

Abstract

Abstract It is known that atmospheric pressure surges affect the discharge of underground water sources in large artesian basins. In southern latitudes, the groundwater tables change insignificantly following the diurnal variations of atmospheric pressure. There is no information on the influence of rapid changes in atmospheric pressure on the position of the surface of the suprapermafrost waters and river flow in the Arctic region. The study of the diurnal course of the level of underground suprapermafrost and surface waters was carried out to identify the links of river flow with atmospheric phenomena and cryogenic processes. It was found that the daily atmospheric pressure drop with an amplitude of 1.2 kPa in the area of the small Ugolnaya-Dionisia river, located in the Anadyr lowland in Chukotka, led to a simultaneous decrease and then an increase in the level of suprapermafrost underground and surface river basin waters by 2.5-7.8 cm. This corresponds to a short-term decrease and then an increase in the river water discharge by more than 3.5 times. To clarify the factors that determine the mechanism of the influence of atmospheric pressure on the water level and river flow, a consideration of the hydrophysical properties of aquifer-containing peat soils was carried out. Compression tests revealed that the elasticity of the peat soils horizon remains within the range of 0-15 kPa, which contributes to a dynamic change in porosity even with a slight change in the external load. This means that the atmospheric pressure changes during weather development are sufficient to modify the water capacity of peat soils and deposit them, and then discharge a part of the suprapermafrost flow. The discovered pressure impact in the tundra soils of the permafrost zone is a unique mechanism for providing plants with moisture during droughts and reducing the risk of tundra fires. As part of the further study of the pressure impact, it is planned to conduct laboratory experiments to determine the quantitative parameters of the change in the peat soils moisture capacity under pressure drops in the atmosphere. Mathematical modeling of the capillary moisture capacity of peat soils will be performed under conditions of ambient load changes. The results of experiments and theoretical studies are assumed to be useful for predicting the flow of bogged-up river basins, design of reclamation, and irrigation of areas of peat soils distribution.