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Regional climate change affects the state of inland water bodies and their water balance, which is determined by a number of hydrometeorological and hydrogeological factors. An integral characteristic of changes in the water balance is the behavior of the level of lakes and reservoirs, which not only largely determines the physical and ecological state of water bodies, but also significantly affects the coastal infrastructure and socio-economic development of the region. This paper investigates the interannual variability of the level of the Ladoga and Onega lakes, the largest lakes in Europe located in the northwest of Russia, according to satellite altimetry data for 1993–2020. For this purpose, we used three specialized altimetry databases: DAHITI, G-REALM, and HYDROWEB. Water level data from these altimetry databases were compared with in-situ records at water level gauge stations. Information on air temperature (1945–2019) and precipitation (1966–2019) acquired at three meteostations located at Ladoga and Onega lakes was used to investigate interannual trends in the regional climate change. Finally, we discuss the potential impact of the lake level rise and regional climate warming on the infrastructure and operability of railways in this region. [ABSTRACT FROM AUTHOR]

The paper deals with the actual situation in Latvia concerning the transport terminal establishment. It presents the theoretical base of the terminal establishment, i. e. transport infrastructure survey, transportation analysis. Location is a key factor for all the transport operators whose main activity is moving freight from one place to another one using different modes of transport. Reduction of the delivery time is one of the elements that could make the important difference when a transport operator is being chosen. That is why transport terminal must be located in hub points of transport and distribution activities. Decisions on terminal placing are extremely important, as they influence indicators of its activity for many years. The method of nonlinear programming for the decision of a problem of an optimal location transport terminal in Latvia is offered in this work. Basic difference of the given method consists in use of nonlinear criterion function in which except distances to the client points connected with the terminal, specific features of a transport infrastructure are considered. For a finding of coordinates of an optimal location of the transport terminal in Latvia is used gradient method. The evaluation of locations for establishment of terminals in Latvia is presented. These terminals will be the first transport terminals in Latvia established according to contemporary requirements and will provide necessary co-operation with big trading companies and other terminals in and out Europe and Russia. [ABSTRACT FROM AUTHOR]