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Climate Change to 2030 Re-defining Terroir. Professor Snow Barlow ASTE, FAIAST Melbourne School of Land and Environment University of Melbourne. The globe is warming at an increasing rate. IPCC 2007. South Eastern Australia is also warming. 2030. TRENDS IN PHENOLOGY Côtes-du-Rhône.
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Climate Change to 2030 Re-defining Terroir Professor Snow Barlow ASTE, FAIAST Melbourne School of Land and Environment University of Melbourne
TRENDS IN PHENOLOGY Côtes-du-Rhône Ganichot, 2002
28 days Vines are and will respond to this warming 10th Apr average pre1998 13th Mar average 1998 and post A shift in ‘average date when grapes reach 21°Brix’of about 28 days for Pinot Noir between 1984-1997 and 1998-2009 Webb, Whetton and Barlow (in press)
Future climates will change in both mean and varianceof temperature and rainfall Models and observations indicate increases in both • Mean temperatures • Temperature Variance resulting in • More hot weather and extreme events • Less change in cold weather • frost uncertain IPCC 2007
Future Environments for Viticulture – Southern Australia • Temperature • + 0.7-1.2 C in 2030 and +2.3- 3.5 C in 2070 • More extreme events – heat waves • Rainfall • - 4% by 2030 and -12-13% by 2070 • Vine water use up + 7% in 2030 and +20-25% 2070 • Runoff is more severely affected • Frost • Difficult to know , but could be worse • Carbon Dioxide • What will 450ppm do ?
Climate driven changes in phenology exacerbate post verasion temperature increases 4.2 °C 2.5 °C Webb, Whetton and Barlow 2008
28 days Vines are and will respond to this warming But is it temperature alone ? 10th Apr average pre1998 13th Mar average 1998 and post A shift in ‘average date when grapes reach 21°Brix’of about 28 days for Pinot Noir between 1984-1997 and 1998-2009 Webb, Whetton and Barlow (in press)
Elevated CO2 increases Canopy Temperature Free air CO2 enrichment -FACE • CO2 enrichment increases crop growth by approximately 20% • CO2 enrichment decreases water loss and increases canopy temperature
Photosynthesis Leaf temperature (0C) Elevated CO2 increases the capacity of the leaf to produce sugar at high temperatures • Leaves are more tolerant of high temperatures at elevated CO2 • Photosynthetic rates and carbon accumulation can be higher at these high temperatures • Potential for high sugar and compressed vinatges Long 1991
Alcohol Contents of wine are increasing Godden & Gishen 2005
A word from Charles Darwin “It is not the strongest of the species that survives, nor the most intelligent that survives.” “It is the one that is the most adaptable to change.”
Climate Change Adaptation Framework Transformation to new climate , Strategic system adaptation Current productivity programs Need good economic models to assist producers define the milestones
Wine industry adaptation to climate change • In situ Adaptation • Irrigation management of extreme events • Secure water • Modified canopy management • Re-evaluate crop load /quality relationships • Evolve wine styles • System Adaptation • Change variety /rootstock • Change row orientation /canopy management • Change wine style • Investigate delays of phenology • Transformation • Same wine style –new terroir • Row orientation • Secure water –surface/ground • Alcohol management • Flavour management
How do these warmer ripening temperatures impact on grape and wine quality ? Webb, Whetton and Barlow 2008
Potential reduction in winegrape value from climate change in 2030 Hunter Valley 5 - 17% Coonawarra 1 - 4% Yarra Valley 4 - 10% Margaret River 3 - 7% Year 2030 Riverina 16- 52% Less impact More impact No price data * measured by surrogate for quality: $/tonne
Grapevine development and maturity is strongly influenced by ambient temperature Jones 2007
Winegrape viticulture is practiced internationally within a relatively narrow latitude band and temperature range 2050Isotherms move poleward by 150-300km - NH area expands ,SH declines Jones 2008
% change in land area with equivalent climate Total Area 1 e.g. Pinot Noir 15.8-19.1ºC 2 C. Sauvignon 19.1-20.2ºC 3 Many 20.2-20.7ºC 4 Shiraz 20.7-22.3ºC 5 Verdelho 22.3-23.4ºC 6 Chenin Blanc 23.4-24.8ºC 2030 mid warming 2050 high warming 2050 low warming
Black Saturday Smoke taint? Damage to vineyards reported Temperature (°C)
In the past 200 years, greenhouse gases have continued to increase, and the Earth has warmed
(°C) +2C +2.2C +1C +1.4C Cabernet Sauvignon Chardonnay VineLOGIC phenology model employed for this analysis (CRCV)
Distribution of varieties (Bearing hectares) in 2002 in selected wine regions of Western Australia (Source ABS)
Warming has dual effects (°C) +2C +2.2C +1C +1.4C Chardonnay Cabernet Sauvignon VineLOGIC phenology model employed for this analysis (CRCV)
Impacts of Climate change on Grape ripening temperatures 4.2 °C 2.5 °C
TRENDS IN PHENOLOGY Côtes-du-Rhône Ganichot, 2002
Australian Phenology Trends for vintage , sugar and alcohol • Australian vintages are moving forward at about 1 day per year • Assuming average sugar accumulations of 1 Be’/week in final stages of ripening • 1 day per year is equivalent of 0.14% sugar per year • AWRI (Creina Stockley) reported today average increases of 0.14% alcohol increase per year over the same period (1990-2003)
TRENDS IN PHENOLOGY Côtes-du-Rhône Ganichot, 2002
Grapevine Phenology Responds strongly to Temperature Greg Jones 2008
Winegrape viticulture is practiced internationally within a relatively narrow latitude band and temperature range
E.g. Chenin Blanc Verdelho Riesling Cooler climate varieties Shiraz Semillon Present Climate Year 2030 mid warming Warmer climate varieties No varietal preference Cab Sauv. Merlot Pinot Noir Chard. Year 2050 mid warming Year 2050 high warming Climate Suitability will move South with Climate Change
2030 lower warming 2030 higher warming 2050 lower warming 2050 higher warming
Adaptive challenges What will happen behind this ‘trailing margin’? Year 2050 lower warming • Current infrastructure and production is concentrated in the traditional irrigation regions (~60%). • Need to find varieties suitable for this warmer ‘trailing margin’.
The temperature sensitivity model Rsq=0.6094
Are these phenology changes driven by more than temperature ?- Carbon Dioxide