Land Surface Temperature Trends Over Central and Southern Europe: Derivation and Analyses of Long-Term (1986–2018) Monthly Maxima

Kurzfassung

Monitoring long-term land surface temperature (LST) time series and analyzing their anomalies and trends are essential for understanding spatial patterns of global warming, particularly in Europe—the fastest-warming continent. In this study, we derived and analyzed monthly maximum LST trends over central and southern Europe at 1 km2 resolution from advanced very high resolution radiometer-based TIMELINE LST data for the period 1986–2018. We found that almost 40% of the study area exhibited statistically significant (p<0.1) positive LST trends. Strongest trends were observed in eastern Europe. Additional hotspots were found on the British Isles, in southern Germany and northern Italy. Comparison of the observed LST trends with ERA5 skin temperature (SKT) trends showed that the climatological pattterns correspond well. Both datasets reveal statistically significant warming trends, though with different magnitudes (LST: +0.80 ± 0.16 K/decade, SKT: +0.50 ± 0.08 K/decade). We further analyzed the LST trends with respect to different land cover classes and elevation ranges. The highest positive LST trends are observed for urban areas, grasslands, and bare areas. Croplands, which constitute more than half of the land area, also showed average trends of >0.5 K/decade and thus significantly contribute to the overall surface warming. In contrast, forested areas showed lower LST trend magnitudes (<0.5 K/decade) and a smaller share of areas with significant trends. With respect to elevation, our results revealed the lowest LST trends below 50 m and at mid-elevation ranges (750–1250 m). Both the magnitude of LST trends and the percentage area with significant trends rise towards both lower and higher altitudes. These results help to understand current warming patterns and demonstrate that long-term, high-resolution LST datasets can be used to study land-climate interactions in depth.