Dynamics of the “La Vueltona” in Picos de Europa (Spain) debris cones during the period 2009-2018.

Debris cones represent a typical landform in temperate high mountain regions. These features show representative periglacial and nival processes in the frame of a dynamic equilibrium. In this work, two debris cones (ahead A and B) located in the “La Vueltona” study area in the Picos de Europa mountain range (N Spain) are analysed. The dynamics of these landforms was studied for a period of 10 years (2009-2018) by means of Digital Elevation Models (DEM) surveyed using a Terrestrial Laser Scanner (TLS). We used the steepest slope line (SSL calculated in the 2009 DEM) to understand the lineal dynamics of the studied debris cones for the whole period. Statistical methods based on multivariate data were used to model the altitude of every location along the SSL for the year 2018. These statistical models used as input the topographic data from 2009 to 2017. The modelled and surveyed altitude for the year 2018 were compared, showing a coherent performance of the modelling approach, with errors within the typical uncertainty of the surveying technique. The Vueltona debris cones showed a wavy dynamics along the SSL, which may be useful to predict their evolution in the short-term. The dynamics model could be extrapolated to other debris cones in temperate high mountain areas.