Micro and Meso Weather Monitoring in Vineyards
On a bottle of wine, you normally see a year imprinted on its label. That represents the ‘vintage’, the year that its grapes were picked. But how is this information important? And what makes one vintage better than another? Answer - the weather. It is one of, if not the most important external factor for the calibre of wine produced. The weather in the vineyard during a given year impacts the health and quality of the fruit produced.
In viticulture practices, winegrowers need to precisely focus on weather conditions surrounding their vineyard, technically termed ‘meso-weather’, and more precisely the environment within the vineyard canopy (such as rows of vines), called the ‘micro-weather’, as opposed to the weather details of a larger area as determined by any local weather station ‘macro-weather’.
Micro-level variables can be considerably different (up to 37%) from that of the macro-level region. One of them is the Soil moisture Content which is specific to the plots. Water stress during developmental stages can cause reductions in shoot growth, poor flower development, and low berry set. In contrast, excessive water availability during the early period in the grapevine growing cycle may overstimulate vegetative growth, which can lead to excessively vigorous and dense canopies, increasing the risk of fungal diseases. Monitoring conditions at the micro-level in vineyards enables improved efficiency of the crop yield and sustainable agricultural practices.
How does weather affect wine?
Real-time weather measurements are important for decision-making regarding the work activities in the vineyard at a given moment. Adequate sun, heat, and water during the growing season are crucial for the healthy growth of vines and the production of premium quality grapes. The sun helps the grapes to ripen (the acid levels drop and sugar starts to accumulate. Moreover, the bitter-tasting tannins change to pleasantly astringent). The greater the number of hours of sunshine, the richer a wine is in polyphenols and the more aromatic the grapes (although excessive heat can often cause over-ripening). Grapevines also need water to thrive (400 and 600 mm of rain per year). It enables vines to take up minerals and stimulates growth and greatly impacts the volume and make-up of the harvest.
Weather patterns, however, are becoming increasingly unpredictable due to climate change. While studies have indicated that initial climate change could prove beneficial with quicker ripening of grapes and new creation of fruitful vineyards in areas that were previously considered too cold to produce quality wine, excessive climate change is predicted to be disastrous. Devastating wildfires have swept through several major wine-producing regions in recent years. Wildfires in California, for example, are becoming increasingly volatile with every passing year. One of the most devastating was the Glass Fire in 2020, which scorched more than 67,000 acres and destroyed over 30 wineries. Vineyards are also vulnerable to the same severe weather events that can destroy other types of crops: early frosts, hail, heat waves, heavy precipitation and flooding, and drought. Warmer temperatures and more precipitation are projected to increase the likelihood of grape insect pests. Downy and Powdery mildew are the most persistent fungal diseases of grapevines in the world. If uncontrolled, they cause serious crop losses and impair wine quality.
Ashok Kare, a grape farmer from Karnataka faced water scarcity during the rest period of the crop. This affects photosynthesis and nutrition storage leading to poor yield. Poor disease management of downy mildew was another major problem in the vineyard.
Impacts of GidaBits® by Yuktix Technologies: GidaBits® is a smart agri-intelligence platform that offers crop-oriented irrigation advisory alongside weather forecasts for better water management in the farmland and provides assistance with disease forecasts. The app-enabled farmers with timely irrigation.
The borewell which used to be exhausted by December was active for two extra months after following the advisories by GidaBits®.
The GidaBits® system calculated disease probabilities which helped the grape farmer apply the required amount of fungicides. This brought down the cost of cultivation by 15%.
Yuktix GidaBits Device Installed in Ashok Kare’s vineyard
Mirás-Avalos JM, Araujo ES. Optimization of Vineyard Water Management: Challenges, Strategies, and Perspectives. Water. 2021; 13(6):746. https://doi.org/10.3390/w13060746
Harner Andrew D., Vanden Heuvel Justine E., Marini Richard P., Elias Ryan J., Centinari Michela. Modelling the Impacts of Weather and Cultural Factors on Rotundone Concentration in Cool-Climate Noiret Wine Grapes. 2019. 10.3389/fpls.2019.01255