Assigned Session: FS 3.115: Drought in mountain regions
Drought, snowmelt, and vegetation stress in the Pyrenees: insights from ecohydrological modeling
Abstract ID: 3.13420 | Accepted as Poster | Poster | TBA | TBA
Katrina Gelwick (1)
Emmy Stigter (1), Michael McCarthy (2, 3), Maximiliano Moreno (2), Álvaro Ayala (2, 3), Franziska Zilker (3), Sergio Contreras (4), Ignacio López-Moreno (5), Simone Fatichi (6), Dirk Karger (3), Francesca Pellicciotti (2), Walter Immerzeel (1)
(2) Institute of Science and Technology Austria (ISTA)
(3) Swiss Federal Institute for Forest, Snow and Landscape Research (WSL)
(4) FutureWater
(5) Consejo Superior de Investigaciones Científicas (CSIC)
(6) National University of Singapore
Droughts are globally becoming more frequent and severe in a warming climate, with significant implications for mountain ecosystems and downstream water resources. In Spain’s Ebro River Basin, the second largest on the Iberian Peninsula, these challenges are particularly acute. Covering 85,362 km², the basin supplies water to over 3.2 million people and supports extensive agriculture. However, declining precipitation (>10% since the mid-20th century) and rising temperatures have led to reduced snowpack and earlier snowmelt onset in the Pyrenees, contributing to more frequent water shortages, lower crop yields, and increased wildfire risk throughout the Ebro region. This study assesses how vegetation in high-elevation Ebro tributaries in the Pyrenees responds to meteorological droughts and the extent to which snowmelt dynamics buffer ecological drought impacts. Using the Tethys-Chloris land surface model, a process-based ecohydrological model, we simulate ecohydrological responses to droughts for the period 2000–2010, which includes several extended dry spells. The model is run at high spatial resolution (250 m) and is forced with downscaled, bias-corrected ERA5 climate reanalysis data to account for the high spatial variability in meteorological conditions in mountain regions. To evaluate the Tethys-Chloris simulations, we compare model outputs with satellite-based products, including MODIS-derived snow cover extent, leaf area index (LAI), and Normalized Difference Vegetation Index (NDVI). These comparisons assess the model’s ability to capture observed vegetation stress and ecosystem variability during droughts. By identifying thresholds in vegetation response, we examine how water deficits propagate across the hydrosphere, cryosphere, and biosphere, altering vegetation function and hydrological stability. Understanding these dynamics improves our ability to predict how mountain ecosystems respond to drought and their role in regulating downstream water availability. These insights are critical for assessing future drought risks to water resources and ecosystem services in the Ebro River Basin.
N/A | ||||||||
|