1. Instituto Dom Luiz, University of Lisbon, 1749-016 Lisbon, Portugal.
2. Institute for Atmospheric and Climate Science, Eidgenössische Technische Hochschule (ETH) Zurich, 8092 Zurich, Switzerland.
3. Department of Geography, Justus-Liebig-University of Giessen, D-35390 Giessen, Germany.
4. Agencia Estatal de Meteorología (AEMET), 28071 Madrid, Spain.