2015_01_07_CIE_johann_martinez

"The increase in temperatures and CO2 levels, a consequence of climate change, accelerate the ripening of grapes in wine production, affecting color and possibly aromas". This has been highlighted by the doctoral thesis defended by Johann Martínez-Lüscher carried out jointly at the University of Navarra and the University of Bordeaux.

Under the degree scroll,"Effects of UV-B radiation on grapevine (Vitis vinífera cv. Tempranillo) leaf physiology and berry composition, framed within the climate change scenario (water deficit, elevated CO2 and elevated temperature), the biologist explained that if the forecasts of the Intergovernmental Panel on Climate Change are fulfilled, and 700ppm of carbon dioxide and an increase of 4ºC are reached,"the accumulation of sugars could be so fast that the rest of the processes that depend on it are not able to keep up. This means that when comparing grapes with the same concentration of sugars or Degree alcohol, those grown in conditions of climate change will have a worse color and this will be perceived in the wine".

In fact,"it is increasingly common to find wines with a high alcoholic Degree due to over-ripening of the grapes". However, in the framework of climate change, the consequences could vary. "For example, changes in ultraviolet radiation levels or a decrease in precipitation could have antagonistic effects to those caused by an increase in temperature or CO2 levels. This creates many unknowns about what to expect in the future," he added.

Wine on a new stage

In this regard, wine production will have to find solutions to meet environmental challenges. "The use of slower maturing 'clones' (subvarieties) could be one of the possible strategies. It could also be very tempting to change the varieties planted in each place for others better adapted to warmer climates, but this would mean giving up to a large extent the typicity of our wines, something unimaginable."

However, as the expert pointed out, climate change may offer new opportunities, for example, the production of a subject of wine in colder climates where it was not previously possible. "This is the case of the fledgling wine industry in the UK where I plan to continue working."

Johann Martínez-Lüscher's research has been funded by the University of Navarra, the Navarra-Aquitaine Cross-border Cooperation Program, the Ministry of Science and Innovation and the 7th Program framework of the European Union.