## 3 Results  
### Climatic Parameters Selected for Mapping  
The created atlas consists of the groups of electronic maps reflecting seven climatic parameters: air temperature, total precipitation, wind speed (main parameters); soil temperature, soil moisture content, air humidity, and snow cover thickness (auxiliary parameters). The first three parameters contain the key information necessary for the analysis and prediction of climatic changes in the region in general [42]. The auxiliary parameters facilitate the assessment of climate change in relation to soil characteristics, snow cover thickness, and air humidity [43]. Let us describe the main groups of the resulting maps and the ways of processing the information for their construction. For each of the parameters, the input data are digital arrays containing the coordinates (with a spatial resolution 0.5\({}^{\circ}\)\(\times\) 0.625\({}^{\circ}\)) and parameter values. These arrays are further structured by time intervals: for main parameters from 1950 to 2021, and for auxiliary parameters from 1980 to 2021. While calculating various characteristics, the used data had certain time sampling, which was as follows:  
* 1950-2021--the entire time interval according to NCEP/NCAR Reanalysis 1;
* 1980-2021--the entire time interval according to MERRA-2 reanalysis data;
* 1980-1999--period when the observed values were less accurate (according to MERRA-2 reanalysis data);
* 2000-2021, the period with the best resolution and modern observation system (according to MERRA-2 reanalysis data). By overlaying the information in each file on the grid, the characteristics were calculated in each node of the grid within the defined period [42]. Each grid node contains data averaged for its vicinity \(\pm\)1.25\({}^{\circ}\). Figure 9: The result of the raster calculator tool application. The data represents the average change in air temperature (\({}^{\circ}\)C) between 1980–1999 and 2000–2021: **(a)** data for January; **(b)** data for July; **(c)** the resulting amplitude map of the average temperature between the two months, January and July. For the main parameters (air temperature, total precipitation, wind speed), the characteristics were calculated starting from 1950, since these parameters were measured in sufficient detail even before the modern satellite observation network was created. An example of such an initial digital map is shown in Figure 10.  
For each combination of climatic parameters, the following groups of characteristics were calculated when creating the initial digital map:  
* Arithmetic means for individual time periods;
* Average parameter changes between the periods 1980-1999 and 2000-2021;
* Average values for each month separately (12 maps);
* Average values by season: summer (June-August), and winter (December-February);
* Average values between the periods 1980-1999 and 2000-2021 for each month;
* Average values between periods 1980-1999 and 2000-2021 by season--summer (June-August), and winter (December-February);
* Average rate of change of mean monthly characteristics. The anomalies shown on the maps for different months allow us to distinguish local changes, as well as to correlate different parameters in time. In this group, the average values are taken as a sample for each day of a certain month for each year of the selected time interval. Since the studied area is the northwestern part of Russia, this zone is characterized by strong temperature fluctuations and, consequently, by strong changes in other parameters. The seasonal analysis makes it possible to trace the intra-annual variability of the parameters. Moreover, there are the maps of differences in values of individual parameters between the periods 1980-1999 and 2000-2021. As this group initially carries information about anomalies for the two certain periods and compares them, it allows for not only tracing regional changes of climatic parameters, but also giving a quantitative assessment of climate change on scale of almost half a century.