Dry Spells and Extreme Precipitation are The Main Trigger of Landslides in Central Europe

Abstract

Landslides are frequently triggered by extreme meteorological events which has led to concern and debate about their activity in a future greenhouse climate. It is also hypothesized that dry spells preceding triggering rainfall may increase slope predisposition to sliding, especially in the case of clay-rich soils. Here we combined dendrogeomorphic time series of landslides and climatic records to test the possible role of dry spells and extreme downpours on process activity in the Outer Western Carpathians (Central Europe). To this end, we tested time series of past frequencies and return periods of landslide reactivations at the regional scale with a Generalized Linear Mixed (GLM) model to explore linkages between landslide occurrences and triggering climate variables. Results show that landslide reactivations are concentrated during years in which spring and summer precipitation sums were significantly higher than usual, and that triggering mechanisms vary between different types of landslides (i.e. complex, shallow or flow-like). The GLM model also points to the susceptibility of landslide bodies to the combined occurrence of long, dry spells followed by large precipitation. Such situations are likely to increase in frequency in the future as climate models predict an enhancement of heatwaves and dry spells in future summers, that would be interrupted by less frequent, yet more intense storms, especially also in mountain regions.

Post‐landslide soil and vegetation recovery in a dry, montane system is slow and patchy

“…Climate change is expected to drive increased landslide rates due to more frequent storms at higher intensity (Dale et al 2001), which historically correlate with higher landslide activity (Borgatti and Soldati 2010, Kirschbaum et al 2010, Zerathe et al 2014). Local studies suggest that increased precipitation intensities will drive substantial increases in landslide rates (Jakob and Lambert 2009, Biasutti et al 2016, Tichavský et al 2019). Broadly, the majority of the United States is expected to see heavier rain events (Easterling et al 2017), and landslide frequency is likely to increase at global scales (Kirschbaum and Stanley 2018).…”

Machine learning for landslides prevention: a survey

“…Some factors, including lithology, slope morphology, and unplanned urban expansions, can predispose slopes to landslides [28,73]. Severe extreme events caused by climate change, including heavy rainfall and rapid snowmelt, could also trigger landslide occurrences [167]. With climate change has strengthened, the frequency and intensity of landslides are expected to increase rapidly as a consequence.…”

Hidden Hazards: the conditions that potentially enabled the mudflow disaster at Villa Santa Lucía in Chilean Patagonia

“…Climate change has a causal link to landslides in mountain environments due to the increase of extreme precipitation mean, minimum-maximum temperature, and heatwaves (Drewes et al, 2018;Huggel et al, 2012;Stoffel and 60 Huggel, 2012;Tichavský et al, 2019). Because this is of great concern for high slope instabilities, we need to understand the concepts of long-term disposition such as geology (lithology, layering, faults), topography (vertical extent, slope) and ice conditions (ice cover, hanging glaciers, permafrost), short-term disposition that can change long term disposition such as climate change, and trigger effects including earthquakes, extreme snowmelt, heat waves, and heavy precipitation that lead to discrete events (Fischer et al, 2012(Fischer et al, , 2013Haeberli, 2013;Huggel et al, 65 2010;Tichavský et al, 2019). In our contribution, we will evaluate the generation of cascade events associated with the Villa Santa Lucia mudflow in the Northern Patagonia.…”

“…Heavy precipitation impacts, on the other hand, usually occur on short scales of time (less than a year) (Huggel et al, 2012). Additionally, (Tichavský et al, 2019) found that more significant sums of annual precipitation 75 are related to landslides, which are enhanced by previous dry spells that can alter soil properties.…”