Dynamics and spatial distribution of snow storage in a large city in the Volga River basin (the case study of Nizhny Novgorod)

Abstract

Processes of formation and melting of snow cover in large cities remain poorly studied, for example, one of those is Nizhny Novgorod, the largest city in the Volga River basin. Using the relationship between the amount of precipitation, falling over the cold season, and the snow storage, formed on the whole territory of the city, that was built taking account of the influence of thaws, a continuous series of values of the snow water equivalent (snow storage) for the time of the snowmelt beginning was restored for the period 1965– 2019. Thaws were taken into account through the use of the sums of positive air temperatures for the cold period, calculated for each individual year of observation. During the period under consideration, the maximum snow storage occurred in 2011, while the minimum – in 1998; and it was close to the average value in 1973. Field snow-measuring surveys in the city and its environs, carried out in 2020, showed that the classical notion of the snow-storm transport is not true in the urban landscapes rather than in the environs. The use of the results of field snow surveys performed in different parts of the city in 2021, as well as the statistical characteristics of the above series of snow storage values, allowed estimating the distribution of the snow water equivalent in catchments of six small rivers in the city Nizhny Novgorod. The assessment is detailed for different types of urban landscapes and for years of different snow conditions, including the extreme ones.

Keywords

• snow storage
• monitoring
• statistical characteristics
• landscape structure
• catchments
• snow melting