mass movement; landslide; dendrogeomorphology; climate change; intense rainfall

Landslides are frequently triggered by extreme meteorological events which has led to concern anddebate about their activity in a future greenhouse climate. It is also hypothesized that dry spellspreceding triggering rainfall may increase slope predisposition to sliding, especially in the case ofclay-rich soils. Here we combined dendrogeomorphic time series of landslides and climatic records totest the possible role of dry spells and extreme downpours on process activity in the Outer WesternCarpathians (Central Europe). To this end, we tested time series of past frequencies and return periodsof landslide reactivations at the regional scale with a Generalized Linear Mixed (GLM) model toexplore linkages between landslide occurrences and triggering climate variables. Results show thatlandslide reactivations are concentrated during years in which spring and summer precipitation sumswere signifcantly higher than usual, and that triggering mechanisms vary between diferent typesof landslides (i.e. complex, shallow or fow-like). The GLM model also points to the susceptibility oflandslide bodies to the combined occurrence of long, dry spells followed by large precipitation. Suchsituations are likely to increase in frequency in the future as climate models predict an enhancementof heatwaves and dry spells in future summers, that would be interrupted by less frequent, yet moreintense storms, especially also in mountain regions.