Application of GIS for the development of climatological air temperature maps: an example from Poland

The main objective of the present study is the construction of air temperature maps for the territory of Poland through the application of contemporary GIS techniques. First a review of currently used spatial interpolation methods is presented. Several spatial interpolation methods have been tested: ordinary kriging, cokriging, universal kriging and residual kriging. The last of these - residual kriging - was chosen for the map constructions. The dataset contains mean monthly temperatures from 168 stations (synoptic and climatological) located across the entire territory of Poland as well as from 55 stations located in bordering zones. Additionally, mean daily temperature data from all synoptic stations have been collected for the 50-year period 1951-2000. Several geographic parameters, including elevation, latitude, longitude, and distance to the Baltic coast (for stations located within 100 km) were used as predictor variables for air temperature interpolation. The first set of maps display the mean annual, seasonal and monthly temperatures for Central Europe and other selected regions. Special attention was paid to temperature parameters which have practical value (e.g. the length of the growing season, duration of thermal summer and winter, and degree day accumulations). GIS tools also enable the easy calculation and display of the area under specified thermal conditions and the display of maps for climate monitoring purposes. An example of the synoptic-climatic analysis with the application of mean daily temperatures and circulation using Grosswetterlagen circulation types is also presented.