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IVES 9 IVES Conference Series 9 Frost variability in the Champagne vineyard: probability calendar

Frost variability in the Champagne vineyard: probability calendar

Abstract

Dans le vignoble champenois, le risque thermique associé au gel des bourgeons au printemps et en hiver est très mal connu et ne peut être envisagé qu’à l’échelle locale, en raison d’une variabilité spatiale forte. L’objectif de l’étude est d’appréhender ce risque de façon fiable et pluri locale en utilisant le réseau de stations météos récemment implanté. Au démarrage de l’étude (1998), nous ne disposons de données thermiques que depuis 5 ans dans le meilleur des cas. Néanmoins, les données sont recueillies sur plus de 30 sites représentant une grande diversité de situations: bas de coteau, mi-coteau, plaine vallée, plateau etc. Nous disposons par ailleurs de plusieurs sites hors vignoble avec de longues séries (plus de 30 ans).
Dans un premier temps, la méthode consiste à élaborer, sur la période courte de 5 ans, une « Composante Thermique Régionale » ou «C.T.R. », composante principale de la variabilité thermique d’un ensemble de stations hors vignoble, disposant de longues séries (plus de 30 ans). Cette C.T.R. est établie de telle façon que les stations hors vignoble puissent reconstituer avec une très bonne fiabilité leurs propres séries longues à partir des données de la série courte.
Dans un second temps, à partir de la C.T.R. et des séries courtes (Sans), des séries longues « fictives » sont reconstituées pour chaque station vignoble. Des statistiques de fréquences de gel pour différents seuils de température sont ensuite établies.
Le résultat est un calendrier présentant pour chaque site, par décade et de janvier à mai, la probabilité de connaître chaque jour, une gelée en deçà d’un seuil de température choisi.
La méthodologie revêt plusieurs intérêts : une meilleure connaissance des terroirs, l’aide au choix économique d’un système de protection contre les gelées et la perspective d’étendre cette méthodologie à d’autres variables climatiques.

In the Champagne vineyard, the thermal risk corresponding to frost damage of buds in spring and winter is badly known and must be only study at thin scale because of its great spatial variability. The objective of this study is to describe this physical risk with a great reliability on several places of the vineyard, using the recently installed meteorological station network. In the beginning of the study, we have date only for five years in the best case. Nevertheless, these data are collected from more than 30 stations, representing a great number of topographie situations: bottom, middle of hills, plains, valleys, We also have out-of-vineyard stations with long thermal series.
At first, the method consist of establishing the C.R.T (Regional Thermal Component), which is the main component of the thermal variability of a set of several out-of-vineyard stations, having long thermal series (more than 30 years). This C.R.T. is elaborated so as to reconstitute with a good reliability out-of-vineyards stations long thermal series from short thermal series.
At last, virtual long thermal series of vineyard stations are reconstituted from both short thermal series and C.R.T. Then, frequency statistics of thermal risk are established for different temperature levels. This method is interesting for 3 reasons : a better knowledge of our vineyard, selecting easily the most cheaper frost protecting system in each situation and extending perhaps this method to other climate parameters.

 

 

 

DOI:

Publication date: February 15, 2022

Issue: Terroir 2002

Type: Article

Authors

F. LANGELLIER, L. PANIGAI, D. MONCOMBLE (1), M-F. de SAINTIGNON, S. DURANTON (2)

(1) COMITE INTERPROFESSIONNEL DU VIN DE CHAMPAGNE, 5 rue Henri Martin 51200 Epernay
(2) LABORATOIRE DE LA MONTAGNE ALPINE- CNRS – Espace Serge Martin- 2061, rue de la Piscine, Domaine universitaire BP 53- 38041 Grenoble Cedex

Keywords

Vignoble de champagne, gel de printemps, risque thermique, réseau météorologique
Champagne vineyard, spring frost; probability calendar, meteorological network

Tags

IVES Conference Series | Terroir 2002

Citation

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