Terroir 1996 banner
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

Related articles…

USING CHECK-ALL-THAT-APPLY (CATA) TO CATEGORIZE WINES: A DECISION-MAKING TOOL FOR WINE SELECTION

Bordeaux is the largest appellation vineyard in France. This contrasting vineyard with varied terroirs offers all styles of wine, resulting from the blending of several grape varieties. If these different profiles make the renown of Bordeaux wines, it can appear as a constraint when the aim is to study Bordeaux wines in their diversity. The selection of a representative sample can be performed by a sensory analysis carried out by trained panelists or by wine professionals, which can take several forms: consensus among experts, conventional descriptive analysis, typicality or quality evaluation. However, because of time, economic, and logistical constraints, these methods have limited applications. As an alternative to classical descriptive analysis, more intuitive methods that do not require training have been proposed recently to describe wines using an expert panel such as Napping, Free Choice or Flash Profiling, CATA or RATA.

Grapevine nitrogen retrieval by hyperspectral sensing at the leaf and canopy level

Grapevine nitrogen (N) monitoring is essential for efficient N management plans that optimize fruit yield and quality while reducing fertilizer costs and the risk of environmental contamination. Unlike traditional vegetative-tissue sampling methods, remote sensing technologies, including hyperspectral imaging, have the potential to allow monitoring of the N status of entire vineyards at a per-vine resolution. However, differential N partitioning, variable spectral properties, and complex canopy structures hinder the development of a robust N retrieval algorithm. The present study aimed to establish a solid understanding of vine spectroscopic response at leaf and canopy levels by evaluating the different nitrogen retrieval approaches, including the radiative transfer model.

Temperature-based phenology modelling for the grapevine 

Historical phenology records have indicated that advances in key developmental stages such as budburst, flowering and veraison are linked to increasing temperature caused by climate change. Using phenological models the timing of grapevine development in response to temperature can be characterized and projected in response to future climate scenarios.
We explore the development and use of grapevine phenological models and highlight several applications of models to characterize the timing of key stages of development of varieties, within and between regions, and the result of projections under different climate change scenarios.

Unconventional methods to delve deeper into the influence of temperature and nutrition on Chardonnay wine profiles

Temperature and yeast nutrition profoundly impact wine quality and sensory attributes by modulating yeast aroma production and release during fermentation. While temperature and nitrogen’s individual effects are well-studied, their combined influence, including nutrient type and addition timing, remains underexplored. hence, this study aimed to investigate the simultaneous effects of these factors on fermentation kinetics, aroma production and sensory profile, particularly in a Chardonnay wine production selected as a quite aromatically neutral base.

Determination of steviol glycosides in wine by HPLC

The SCL laboratory in Bordeaux is one of the two official control laboratories for wine and wine products in france, under the authority of the ministry of finance and two of its general directorates: the DGCCRF (directorate general for competition, consumer affairs and fraud control) and the DGDDI (directorate general of customs and excise duties). In this capacity, it verifies the regulatory compliance of wines and investigates any possible falsifications or fraud. Steviol glycosides are natural sweeteners that are not authorized as additives in wine.