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IVES 9 IVES Conference Series 9 A viticultural perspective of Meso-scale atmospheric modelling in the Stellenbosch wine growing area, South Africa

A viticultural perspective of Meso-scale atmospheric modelling in the Stellenbosch wine growing area, South Africa

Abstract

La brise de mer et les facteurs climatiques qu’elle entraîne (accélération de la vitesse du vent au cours de l’après midi, augmentation de l’humidité et baisse de la temperature) sont d’un intérêt particulier pour la viticulture. La configuration climatique de la région, comprenant l’effect de la brise de mer, en parallèle avec des donnés pédologiques, viticoles et oenologiques sont étudiés afin de determiner les implications sur la croissance et le fonctionnement de la vigne et potentiellement sur la composition du raisin et le caractère du vin et de bien comprendre les interactions terroir/vigne/vin.
Le modèle atmosphérique RAMS (Regional Atmospheric Modelling System) a été utilisé afin d’étudier le degré de pénétration de la brise de mer et les caractéristiques climatiques (température, humidité relative et vent) qui en résultent, en parallèle avec des données en surface enregistrées par des stations agroclimatiques situées dans le vignoble. Des parcelles expérimentales de Sauvignon blanc situées dans les vignes commerciales sont associées à chaque station météorologique automatique. Les mesures viticoles et oenologiques de ces parcelles sont utilisées comme base pour étudier l’impact de la pénétration de la brise de mer et du topoclimat, en conjonction avec d’autres composantes du terroir, sur la viticulture de la région d’étude. Les résultats des analyses statistiques soulignent l’importance du climat, particulièrement les caractéristiques liées à la brise de mer.

The sea breeze and induced climatic patterns (increase in wind velocity in. the afternoon with a concomitant increase in relative humidity and reduction in temperature) are of particular interest for viticulture. The climatic patterns of the area, including the sea breeze effect, along with soil, viticultural and oenological data were studied in order determine the implications for vine growth and functioning, and, potentially, berry composition and wine character and to fully understand the terroir/vine/wine interactions.
The Regional Atmospheric Modelling System (RAMS) was used to study the degree of penetration by the sea breeze and the resulting climatic characteristics (temperature, relative humidity and wind) along with surface data recorded at agroclimatic stations situated in the vineyards. Associated with the automatic weather stations are experimental plots of Sauvignon blanc within commercial vineyards. The measured viticultural and oenological attributes of these plots were used as a basis to assess the impact of the sea breeze penetration and topoclimate, in conjunction with other terroir components, on viticulture in the study area. Results of statistical analyses emphasized the importance of the climate, especially sea breeze related characteristics.

DOI:

Publication date: February 15, 2022

Issue: Terroir 2002

Type: Article

Authors

V.A. CAREY (1) and V.M.F. BONNARDOT (2)

(1) ARC Infruitec-Nietvoorbij, (Present address: Department of Viticulture and Oenology, Stellenbosch University, Private Bag Xl, 7602 Matieland, South Africa)
(2) ARC Institute for Soil, Climate and Water, Private Bag X5026, 7599 Stellenbosch, South Africa

Keywords

Modélisation Atmosphérique, brise de mer, humidité relative, température, Sauvignon blanc
Atmospheric Modelling, sea breeze, relative humidity, temperature, Sauvignon blanc

Tags

IVES Conference Series | Terroir 2002

Citation

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