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IVES 9 IVES Conference Series 9 Système de Classification Climatique Multicritères (CCM) Géoviticole

Système de Classification Climatique Multicritères (CCM) Géoviticole

Abstract

Le travail concerne en premier la méthodologie de caractérisation du climat des vignobles, à l’échelle du macroclimat des régions viticoles du monde (géoviticulture). Trois indices climatiques viticoles synthétiques et complémentaires (hydrique, héliothermique et nycthermique), validés comme descripteurs, sont utilisés :

1) Indice de Sécheresse – IS, qui correspond à l’indice de bilan hydrique potentiel de Riou, adapté ici dans des conditions précises de calcul, comme indicateur du niveau de présence-absence de sécheresse;

2) Indice Héliothermique – IH, qui correspond à l’Indice héliothermique de Huglin;

3) Indice de Fraîcheur des nuits – IF, indice développé comme indicateur des conditions nycthermiques de maturation.

Ces indices sont représentatifs de la variabilité du climat viticole mondial liée aux exigences des cépages, à la qualité de la vendange (sucre, couleur, arôme) et à la typicité des vins. Le Système de Classification Climatique Multicritères Géoviticole (Système CCM Géoviticole), pour les régions viticoles au plan mondial est formulé sur la base des classes pour chacun des 3 indices climatiques, avec les éléments d’interprétation des résultats. Trois concepts formulés sont à la base du système : climat viticole, groupe climatique et climat viticole à variabilité intra-annuelle (pour les régions à plus d’une récolte par année). L’application du Système CCM Géoviticole est présentée sur une centaine de régions viticoles dans 30 pays. Le système est un outil de recherche dans le domaine du zonage vitivinicole. Il permet également de travailler à différents niveaux d’échelle, soit à l’échelle mondiale, soit à l’échelle plus grande – grande région viticole, petite région viticole, comme le démontrent les études réalisées. Il permet de mettre en relation le climat viticole et les éléments de la qualité du raisin et de la typicité des vins en fonction de la zone climatique.

DOI:

Publication date: February 24, 2022

Issue: Terroir 2000

Type: Article

Authors

Jorge TONIETTO, Alain CARBONNEAU

Keywords

vigne, macroclimat, mésoclimat, indices climatiques, classification climatique, système CCM géoviticole, qualité, typicité, vin, A.O.C., zonage, terroir

Tags

IVES Conference Series | Terroir 2000

Citation

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