Snow cover in Spanish mountains is crucial for ensuring water availability in spring and summer months, for the success of winter tourism or for the maintenance of biodiversity in mountain ecosystems. A changing climate may affect the volume of snow cover even in high mountains, where weather conditions are usually favorable for snow accumulation. In this paper, we aim to investigate the evolution (1970-2007) of combined precipitation-temperature modes in the Spanish mountains, and the sensitivity of the snowpack to their occurrence. The climatic database >Spain02> and snow thickness data for Spanish mountains were used for this purpose. Results showed that the frequency of dry-warm and wet-warm days has increased over time in all mountain ranges, while the frequency of the >cold> modes has decreased. The thickness of the snowpack in the Pyrenees has also decreased and its evolution is negatively correlated with the frequency of dry-warm days, and positively correlated with the frequency of dry-cold and wet-cold days. This work constitutes the first approach that relates the evolution of climatic conditions favorable or unfavorable for snow accumulation and the evolution of the snowpack in Spanish mountains. © 2012 Springer-Verlag Berlin Heidelberg.

This work has been possible thanks to the financial support of the Spanish Government (Ministry of Education) through the postdoctoral program “Ayudas de movilidad postdoctoral en centros extranjeros (Orden EDU/2728/2011, de 29 de septiembre).” The authors would like to give special thanks to Fernando Pastor Argüello, from the ERHIN program (Ministry of Environment of Spain), for providing the snow thickness data.

Peer Reviewed