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European forests are an important source for timber production, human welfare, income, protection and biodiversity. During the last two decades, Europe has experienced a number of droughts which have been exceptional within the last 500 years, both in terms of duration and intensity. These droughts seem to leave remarkable imprints on the mortality dynamics of European forests. However, systematic observations on tree decline, with emphasis on a single species, has been scarce so far so that our understanding of mortality dynamics and drought occurrence is still limited at a continental scale.Here, we make use of the ICP Forest crown defoliation dataset, permitting us to retrospectively monitor tree mortality for all major conifers, major broadleaves, as well as a pooled dataset of minor tree species in Europe. In total, we analysed more than three million observations gathered during the last 25 years and employed a high‐resolution drought index which can assess soil moisture anomaly based on a hydrological water‐balance and runoff model.We found overall and species‐specific increasing trends in mortality rates, accompanied by decreasing soil moisture. A generalized linear mixed model identified a previous‐year soil moisture anomaly as the most important driver of mortality patterns in conifers, but the response was not uniform across the numerous analysed plots.We conclude that mortality patterns in European forests are currently reaching a concerning upward trend which could be further accelerated by global change‐type droughts in the near future. [ABSTRACT FROM AUTHOR]

ABSTRACT The Lisflood rainfall-runoff model was forced by the E- OBS () gridded meteorological dataset in order to produce 5-km resolution maps of root zone soil moisture for the period 1951-2013, which were used to evaluate the presence of significant trends in soil water deficit over Europe. The results of the trend analysis highlighted a clear subdivision of the European domain into two sub-regions: a southwest portion with mostly positive trends (drying of the soil) and a northeast part with decreasing soil water deficit. Overall, about 19% of the domain was affected by a significant linear trend according to the Mann-Kendall test and the false discovery rate ( FDR) procedure ( p = 0.05), with about 11.6% having a negative (wetting) and 7.6% a positive (drying) slope. A spatial cluster analysis identified 11 major areas (with extension > 10 000 km2) affected by significant trends, including the Ebro and Garonne basins (for positive slopes) and the Dniester watershed (for negative trends). A final analysis at national and sub-national levels highlights that most of the observed trends are also significant when aggregated at a regional ( NUTS-1) spatial scale, detecting the administrative areas where water management planes are most likely affected. As drying and wetting processes are occurring mainly in the already driest and wettest sub-areas of the modelling domain, respectively, the obtained results suggest a further polarization of the water deficit in Europe. [ABSTRACT FROM AUTHOR]