Slushflows at El Port del Comte, northeast Spain

Abstract

Slushflows were first recorded in the Iberian Peninsula on 18 December 1997. Three slushflows were released at the ski resort of El Port del Comte, in the Catalan Pyrenees, northeast Spain, during intense rainfall. Two of the slushflows originated on the pistes, and the third affected another piste. Three ski lifts were damaged. This paper analyzes the hydrogeological characteristics of the massif, the geomorphic features of the terrain and the meteorological and snowpack conditions that caused the release of the slushflows. Man's role in triggering the slushflows by compacting snow on the pistes is also considered. Drainage control for reducing the hazard is outlined, taking into consideration the low frequency of the phenomenon.

Meteorology, Topography and Snowpack Conditions causing Two Extreme Mid‐Winter Slush and Wet Slab Avalanche Periods in High Arctic Maritime Svalbard

“…Both Hestnes () and Furdada et al . () reported slush avalanches that were initially triggered by wet slab avalanches. Wet slab avalanche‐triggering events can also explain the unusually steep starting‐zone inclinations of 30‒46º (Figure ), compared to the ≤ 20º suggested in the literature (Nobles, ; Onesti, ; Hestnes, ).…”

“…Slush avalanches triggered by rain‐on‐snow events in mid winter have also been reported from many locations along the west coast of mainland Norway (Hestnes, ; Hestnes and Sandersen, ; Hestnes et al ., 2004). Snow slush avalanches triggered by mid‐winter rain also occurred in Spain in December 1997 (Furdada et al ., ). However, we have found no reports of mid‐winter slush avalanche events of comparable size elsewhere in the Arctic.…”

“…The Norwegian Geotechnical Institute devoted much of its scientific efforts to examining slush avalanche occurrences and trigger mechanisms (Hestnes, ; Hestnes and Sandersen, ; Onesti and Hestnes, ) on the mountainous, maritime‐influenced west coast of Norway, where they periodically destroy infrastructure (Hestnes, ). More recently, studies in Iceland (mid‐winter rain‐on‐snow event; Decaulne and Saemundsson, ) and Spain (Furdada et al ., ) have provided detailed descriptions of slush avalanche events, while Jaedicke et al . () carried out work on slush avalanche dynamics simulations.…”

Unprecedented Winter Rainfall Initiates Large Snow Avalanche and Mass Movement Cycle in New Zealand's Southern Alps/Kā Tiritiri o te Moana

“…While NZ's maritime climate generates rain‐on‐snow events to high elevations, the intensity and timing of this mid‐winter storm falling on an above‐average snowpack created conditions for an extreme wet avalanche cycle. Similar conditions have been documented in NZ (Fitzharris, 1976) and elsewhere (Decaulne & Sæmundsson, 2006; Eckerstorfer & Christiansen, 2011; Furdada et al., 1999). Characterizing such conditions will help better‐anticipate future hazards, as wet avalanche activity may increase with a warming climate (Ballesteros‐Cánovas et al., 2018; Castebrunet et al., 2014; Lazar & Williams, 2008) and rain‐on‐snow events may be more frequent at higher elevations (McCabe et al., 2007; Musselman et al., 2018).…”