South Africa Wine Technical Yearbook 2025

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SHUTTERSTOCK

In the second part of the Terroir Series, we continue to examine the influence climate has on terroir. We will also examine the role of cultivars in terroir. Finally, we will conclude with something new and not yet defined by terroir: the influence of different microorganisms on the taste and quality of wine and how they fit into the terroir concept. The fascinating world of terroir in winemaking (Part 2): How nature, tradition and science come together By Zukhanye Fondile, Tracey-Lee Johannes, Relebohile Mabaleka, Zinhle Msiza, Imi Mxabo, Ziphozinhle Nkosi, Neo Segopolo, Ezile Zitha & Anton Nel

How climate change is shaping the future of winemaking Climate change is no longer just an abstract issue, but a reality that’s reshaping industries across the globe – especially the world of winemaking. As renowned wine scientist John Gladstones (2011) explores in his book Wine, Terroir and Climate Change , rising temperatures, shifting precipitation patterns and extreme weather events are already having profound effects on vineyards. Here’s how climate change is rewriting the rules for the wine industry. Climate and grape development The climate is another significant factor affecting grape quality, and it operates on three levels: macroclimate

(regional), mesoclimate (site-specific) and microclimate (vine canopy level). Of these, microclimate has the most direct influence on grape development. Different grape varieties thrive in varying climates, and changes in temperature during the growing season can accelerate or slow down the ripening process. Cooler conditions tend to favour more gradual sugar, acid and flavour development, leading to more complex and aromatic wines (Van Leeuwen & Seguin, 2006). In warm climates, grapes ripen more quickly, resulting in higher sugar levels, but lower acidity, which can unbalance the wine’s overall flavour. Grapes should ripen during the cooler end of the growing season to fully express the terroir’s unique qualities (Van Leeuwen et al ., 2007).

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TECHNICAL YEARBOOK 2025