It is widely accepted that climate and viticulture are strongly tied and for this reason the majority of the wine growing regions producing wines of quality are currently located in specific geographic locations. Within these ranges (approximately between the 35th and 50th parallels in the Northern hemisphere and between the 30th and 45th parallels in the Southern hemisphere) climatic conditions (thermal and hydrologic) are favourable the production of wines of high quality.
Outside these limits for example, in tropical regions vines do not enter dormancy while in regions at higher latitudes vines facing spring frost injuries. Under further warming renowned winegrape region will be facing the risk of relocation to northern parts and to the coasts while areas where their climatic conditions could not support viticulture are likely to be possible in the future.
Air temperature is the most important determinant of viticulture since it is strongly connected with:
- The onset of the basic developmental stages
- Grape ripening
- Total yield production
Grapevines have four main developmental stages: (a) budbreak, (b) flowering, (c) véraison and (d) harvest. The time between these events greatly influenced by air temperature. For example, five consecutive days with average temperature above 10oC could initiate budbreak while extreme weather conditions thereafter may significantly advance maturity and harvest especially during the ripening period.For example temperatures above 25oC and 30oC could decrease net photosynthesis, berry size and weight as well as colour and aromatic intensity. In addition, extreme heat above 35oC could increase the risk of grape skin damage from sunburn.
2.2 Precipitation and solar radiation
Precipitation is another crucial factor which affects vine growth. Despite the fact that grapevines are resilient to dry conditions, extreme water deficit of both the current and the preceding years could impair photosynthesis of the plant resulting in unbalanced fruit composition and lower yield production. On the other hand light intensity increases vines photosynthesis.
2.3 Bioclimatic indices
On a global scale, scientists mainly using daily observations of maximum and minimum air temperature and precipitation as inputs to calculate a list of bioclimatic indices widely used in viticultural studies. The most important indices commonly used in viticultural studies are:
(1) Growing season average temperature (GST)
(2) Growing degree days or Winkler index (GDD or WI)
(3) Huglin index (HI)
(4) Biologically effective degree days (BEDD)
(5) Dryness index (DI)
(6) Cool night index (CI)
These bioclimatic indices efficiently used for winegrape region categorization. They also appear to be particularly useful in assessing the potential ripening of many varieties and wine styles that can be produced as well as predicting the main phenological stages.
- Jones, GV, Davis, RE. 2000. Climate influences on grapevine phenology, grape composition, and wine production and quality for Bordeaux, France. Am. J. Enol. Viticult. 51: 249– 261.
- Jones, GV, White, MA, Cooper, OR, Storchmann, K. 2005. Climate change and global wine quality. Clim. Change 73: 319– 343.
- Van Leeuwen and Darriet 2016. The impact of climate change on viticulture and wine quality. Journal of wine economics. 11: 150-167.
- Kenny, GJ, Harrison, PA. 1992. The effects of climate variability and change on grape suitability in Europe. Journal of Wine Research 3( 3): 163– 183.
- Moriondo, M, Jones, GV, Bois, B, Dibari, C, Ferrise, R, Trombi, G, Bindi, M. 2013. Projected shifts of wine regions in response to climate change. Clim. Change 119( 3–4): 825– 839.
- Mullins, MG, Bouquet, A, Williams, LE. 1992. Biology of the Grapevine. Cambridge University Press: Cambridge.
- Duchêne, E, Schneider, C. 2005. Grapevine and climatic changes: a glance at the situation in Alsace. Agron. Sustain. Dev. 25: 93– 99.
- JacksonandLombard 1993. Environmental and management practices affecting grape composition and wine quality-A review. Am. J. Enol. Vitic. 44:409-430.
- Cifre, J, Bota, J, Escalona, JM, Medrano, H, Flexas, J. 2005. Physiological tools for irrigation scheduling in grapevine (Vitis vinifera L.). An open gate to improve water‐use efficiency? Agric. Ecosyst. Environ. 106: 159– 170.
- Huglin, MP. 1978. Nouveau mode d’évaluation des possibilités héliothermiques d’un milieu viticole. In Proc Symp Int sur l’ecologie de la Vigne. Ministère de l’Agriculture et de l’Industrie Alimentaire: Constança, Romania, 89–98.
- Gladstones, J. 1992. Viticulture and Environment. Winetitles: Adelaide.
- Riou, C, Carbonneau, A, Becker, N, Caló, A, Costacurta, A, Castro, R, Pinto, PA, Carneiro, LC, Lopes, C, Clímaco, P, Panagiotou, MM, Sotez, V, Beaumond, HC, Burril, A, Maes, J, Vossen, P. 1994. Le déterminisme climatique de la maturation du raisin: application au zonage de la teneur em sucre dans la communauté européenne. Office des Publications Officielles des Communautés Européennes: Luxembourg, 322.
- Tonietto, J, Carbonneau, A. 2004. A multicriteria classification system for grape‐growing regions worldwide. Agric. For. Meteorol. 124: 81– 97.
- Wikler, AJ, Cook, JA, Kliewer, WM, Lider, LA. 1974. General Viticulture. University of California Press:Berkely, CA; Los Angeles, CA.