There was a time when exceptionally warm and dry years produced excellent vintages of wine. The warm and moderately dry summers favored a complete and balanced ripening of the grapes. On the other hand, in colder and rainy years, the grapes did not ripen properly, and growers could be forced to harvest early to avoid fungus in the clusters development . The increase in temperature coupled with periods of more intense summer drought has favored the production of high quality vintages in appellations around the world. Nowadays, it is rare to find summers that are not dry and warm enough, but we are beginning to feel the impact of extreme heat and drought episodes, to the point where vines in some regions of Spain are dying due to high temperatures and lack of water.

Climate change, a threat to wine typicity
Wines are result of theterroir, a combination of the characteristics of the soil, the plant, the cultivation techniques and the climate. The terroir affects the development of the vine and the composition of the grapes, so that each wine region gives rise to wines with clearly identifiable characteristics, which define their quality and style, that is, their typicity. This typicity is what makes a wine recognizable throughout the world. However, with climate change, the climatic variable in this equation is changing at a rapid pace, making it increasingly difficult to maintain this typicity. Over the last 40 years, there has been a progressive advancement of harvest dates in most of the world's wine regions and grape ripening takes place during the hottest part of the summer, thus under more extreme environmental conditions. As a consequence, fresh and floral aromas are replaced by profiles more similar to cooked fruit. Acidity decreases in favor of sugar accumulation, resulting in wines that are less fresh, with higher alcohol Degree and, in the case of red wines, with a more subdued color.

Transition to irrigated viticulture
If CO2 emissions are not drastically reduced, temperatures are expected to continue to rise in the coming decades and heat waves will become more frequent and intense. Under these conditions, even if rainfall is maintained, which seems unlikely, crop water consumption will be significantly higher. In the Mediterranean area , vines have historically been grown without water input. However, climatic conditions are leading some countries, such as Spain, to start implementing irrigation in this crop. Even guaranteeing a rational and efficient use of water, the increase in the area of irrigated vineyards will contribute to increase the pressure on this limited resource , and the vine will enter skill with other essential crops to ensure food security.

Adapting to a warmer and drier future
Adaptation to climate change is one of the main challenges facing the wine industry in the coming years. Short-term adaptation strategies, in addition to irrigation, include the employment of new viticulture techniques, such as plant covers, shading nets, or different vegetation management systems, among others. In the longer term, there is the possibility of changes in varieties/clones or rootstocks with later ripening or greater drought tolerance. However, there is a point of no return where the migration of vines to higher latitudes and altitudes is contemplated. At Biodiversity and Environment Institute BIOMA of the University of Navarra, we investigate the response of different varieties and rootstocks to climate change (RIZHOCLIMAVID¹ and CARVITRANS² projects) or more novel strategies such as the application of ripening modulators (project CLIMAVITIS³) or the employment of beneficial microorganisms present in the soil. 

The world is changing and so are consumer preferences. There are ways to adapt and mitigate certain aspects of climate change. However, it is to be expected that, as a result of climate change or as a consequence of adaptation measures, the typicity of our wines will be affected to some extent forever.

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1 project of research and development+i / PID2020-118337RB-I00 funded by MICIN/AEI/10.13039/501100011033.

2 project of research and development+i / PID2023-151816OA-I00 funded by MICIU/AEI/10.13039/501100011033 (24/10/24 at proposal of resolution final).

3 project in the framework of the Program for the promotion of partnership in actions of research and development+i between Autonomous Communities. Funded by the Recovery, Transformation and Resilience Plan, the European Union-NextGeneration EU, MICIN and the Government of Navarra. Managed by the Eatex Food Innovation Hub.

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Inmaculada Pascual Elizalde Professor of the School of Sciences of the University of Navarra. Johan Martinez-Lüscher Professor of the School of Sciences of the University of Navarra. 25.11.2024