Climate trends in a specific Mediterranean viticultural area between 1950 and 2006

Abstract

Aims: An analysis of climate data between 1950 and 2006 in the Hérault department, situated in the Mediterranean of France is presented.

Methods and results: Data presented include the evolution of mean annual and seasonal temperatures, the Huglin index, total solar radiation, night freshness index, the distribution and efficiency of rainfall and potential evapotranspiration (pET). Results showed an increase in mean annual temperatures of +1.3 °C between 1980 and 2006 and an increase in the mean pET which was 900 mm / year since 1999. Also, harvest dates advanced by up to three weeks and sugar concentrations at harvest increased by up to 1.5 % potential alcohol.

Conclusion: The indicators show that in this area certain climatic parameters have evolved over the period studied. Changes are observable in some of the parameters (notably temperature) for the last 30 years whereas others have evolved only in the past few years (e.g. pET). Therefore it is necessary to be circumspect in drawing conclusions on climate change in the area, particularly as regards the possible consequences for viticulture. However, at the plot level, it is clear that irrigation of the vines is becoming increasingly necessary in this region.

Significance and impact of study: Climate is a major factor in vine cultivation and in the understanding of viticultural terroirs and wine typicality. The climate trends observed over a 50-year period are discussed in the viticultural context of a Mediterranean region. However, the interaction between climate change and technical progress in viticulture and oenology complicate the analysis over the time frame under consideration.