Bibliogr. 144-146

The main goal of the work is to present contemporary possibilities of using climatological data sources, which are increasingly stored in the form of grids. The essence of these data was discussed against the background of traditional data based on classic station measurements (in-situ). The most famous available databases and their advantages are presented, which allow for their convenient use using GIS. In the last part, gridded data from the ERA5 database was validated based on in-situ data for Poland. Daily air temperature and precipitation values from the period 1991–2020 were taken into account for the analysis. The results indicate a good quality of the gridded data used in the case of average temperature values, however poorer in the case of daily minimum temperature values as well as daily precipitation sums. The research results confirm that gridded data offers many possibilities for regional analyses, but for some micro-scale application purposes it may be not sufficient enough.