Home – Home – Jornals – Geography and Natural Resources 2021 number 3

The spatial and temporal aspects of the dynamics of the annual runoff and the trends in air temperature and precipitation were analyzed to identify regional and local features of the hydrological regime of rivers in the permafrost zone in the territory of Krasnoyarsk krai. Nine river basins located within three landscape zones: forest-tundra, and northern and middle taiga were selected as test sites. To make clear the influence of climatic factors on hydrological regime of the study area the database of long-term hydrological and meteorological observation data was created. Generation of the database used archival material of the Central-Siberian Administration for Hydrometeorology and Environmental Monitoring: long-term observational data on the runoff at hydrological stations, and air temperature and precipitation at weather stations in the study area. The database thus generated was used in constructing models of annual river runoff formation depending on climatic factors, and in analyzing spatial-temporal characteristics of river runoff formation. Investigations showed that the landscape differentiation of the territory influences the spatial distribution of climatic characteristics and, accordingly, the features in the hydrological regime. For all the watersheds under study, regression equations were obtained, which reflect the relationship between river runoff and air temperature and precipitation. For the average annual runoff, precipitation and air temperature during a warm period are most significant, whereas for the winter runoff low the liquid precipitation and air temperature in the winter months are more important. Analysis of linear trends in average annual air temperatures and precipitation showed that since the mid-1950s there has been a steady increase in air temperature, whereas the precipitation trends have not only significant differences in absolute values but differ in sign. Analysis of the dynamics of the annual and minimum winter runoff of the rivers studied in different observation periods showed that most of the rivers are characterized by a positive trend of the annual runoff varying from 0.57 to 4.76 mm/year. The winter runoff increased from 0.09 to 1.42 mm/year. This indicates a general trend for an increase in river discharge in the study area. The opposing trends observed in the river runoff and precipitation show that the thawing of permafrost caused by an increase in air temperature becomes a more significant formation factor for the river runoff in the permafrost zone.