WINETECH Technical Yearbook 2020

TABLE 1. Regional average mean (T m ), maximum (T x ), minimum (T n ) temperatures and rainfall (mm) for 30 years.

Region

T m

T x

T n

Annual Rainfall (mm)

Breede River Valley

17.91

24.77

11.07

293.7

Boberg

17.64

23.42

11.89

786.6

Cape South Coast

16.37

22.40

10.39

702.0

Coastal Region

17.92

24.27

11.57

478.7

Olifants River

19.34

27.05

11.64

255.7

Klein Karoo

17.85

24.53

11.18

331.8

higher resolution, which could aid in more insightful within-season decision making and adaptive strategies for a warmer (or cooler) future. Future work includes the integration of climate maps in the context of grapevine modelling along with a spatial view of the seasonal shifts (www.terraclim. co.za) for improved management and adaptation. SUMMARY In the context of climate change, factors such as seasonal variability and limitations of available water resources, have increased pressures on the production of table wines, and could continue to do so without effective adaptive strategies. Almost every response of the grapevine is affected by climate, it has been scientifically shown that grapevine growth tempo, as well as final shoot length,

are linked to seasonal variability and water constraints. Viticulture actions amidst the increased seasonal variable is forcing us to be more on the seasonal weather pattern pulse. When processing long-term climate change in the Western Cape, it was clearly highlighted that our climate is warming in maximum temperatures and cooling in minimum temperatures. The data highlighted that months and regions within the Western Cape are responding differently within the reality of climate change. Understanding the seasonal patterns for specific regions and months within that region is important to aid effective adaption in the context of climate change.

FIGURE 2. Average climate change over 30 years for each wine-producing region.

For more information, contact Tara Southey at tara@sun.ac.za.

FIGURE 3. Normalised temperature and rainfall differences for months of the year for the extent of the Western Cape.

WINETECH TECHNICAL YEARBOOK 2020 21