Climate Twin Methodology for Assessing the Future Viability of European Vineyards: A Bioclimatic and Topographic Approach

The repercussions of climate change on viticulture are a matter of increasing concern, particularly in Europe, where vineyards are intrinsic to both the economy and cultural heritage. In order to facilitate a more profound comprehension of the spatial change of the climate, the climate twin method [1] is employed to analyse the case of European vineyards. The methodology involves the use of a climate twin model, which matches future vineyard climates with those of other regions. This provides insights into how shifting climates may influence the suitability of current and potential vineyard regions. The approach enables an understanding of both current and future climate conditions in wine-producing regions, offering prospective insights into the potential shift of suitable vineyard locations. The employment of the climate twin method facilitates the identification of regions within Europe that will retain their suitability for viticulture under future climate conditions, whilst concomitantly enabling the discovery of new areas with wine-growing potential in the future.

We rely on several bioclimatic indices, that consider climate conditions in the context of vineyard growth and disease development. The Huglin index and the number of heat and frost days are employed to describe the optimal conditions required for vine growth. The Scaphoideus titanus, the vector of Flavescence dorée, as well as the downy and powdery mildew, which are the main threats to European vineyards, are also considered. The climate twins are computed using these bioclimatic indices, as well as the raw climate data, namely temperature, precipitation, humidity and solar radiation. Results show that using the bioclimatic indices yields consistent mappings region by region, with a specific region being reliably associated with another under future climate conditions. 

Topography is a pivotal factor in viticulture, with vineyards frequently situated in hilly regions with south-facing slopes to maximise sunlight exposure. These topographic characteristics modify temperature, thereby influencing vine growth and disease dynamics. In this study, we analyse the impact of topography by calculating temperature corrections based on slope orientation and altitude. We show that the influence of these adjustments plays an important role on the identification of climate twins, and subsequent predictions for vineyard viability under future climate scenarios.

The findings of this study offer a more robust understanding of how European viticulture will need to adapt to climate change, with a particular focus on spatial shifts in suitable regions. This will assist winegrowers in making informed decisions regarding vineyard locations, culture management strategies, and future investments in viticulture. Our study underscores the significance of the climate twins approach to understanding climate impacts on viticulture, taking into account both bioclimatic variables and topographic factors. The overarching objective of this research is to provide a scientific foundation for the sustainable viticulture practices that will be required in the face of ongoing climate change, thereby safeguarding the future of European winemaking.

[1] G. Rohat, S. Goyette, J. Flacke, International Journal of Climate
Change Strategies and Management (2017)