Climatic zoning and viticulture in Galicia (North West Spain)

Galicia is situated in the NW of the Iberian Peninsula, just north of Portugal and so sharing a mild, maritime climate, certain vine species and a number of long-standing viticultural traditions. In Galicia about 18,000 has are dedicated to wine growing, of which roughly half (46%) correspond to the 6 DOs in the area. The Galician climate is marked by its great diversity that can be explained by the prevailing maritime and continental winds over this part of the world and also due to its topography where a series of N to S mountainous chains check rain-bearing fronts from the Atlantic. This factor gives rise to the appearance of rain shadows particularly suitable for vine growing. A database was established with standardised 1971-2000 climatic data from 53 selected stations. Fourteen parameters and climatic indices commonly used in viticulture zoning studies were calculated. An analysis of principal components identified the main factors related to climatic variability as well as the climatic indices and parameters with major discriminating scores. These indices included those selected by the Geoviticulture Multicriteria Climatic Classification System (GMCCS). Results show that 13 out of the 36 worldwide viticulture climates specified by the GMCCS appear in Galicia confirming the diversity of viticultural climates present in the region. These results also demonstrate the efficacy of the GCCM system for the differentiation of climatic types on a regional level reinforcing the system’s versatility.