terclim by ICS banner
IVES 9 IVES Conference Series 9 Mechanisms involved in the heating of the environment by the aerodynamic action of a wind machine to protect a vineyard against spring frost

Mechanisms involved in the heating of the environment by the aerodynamic action of a wind machine to protect a vineyard against spring frost

Abstract

One of the main consequences of global warming is the rise of the mean temperature. Thus, the heat summation by the plants begins sooner in the early spring, and by cumulating growing degree-days, phenological development tends to happen earlier. However, spring frost is still a recurrent phenomenon causing serious damages to buds and therefore, threatening the harvests of the winegrowers. The wind machine is a solution to protect fruit crops against spring frost that is increasingly used. It is composed of a 10-m mast with a blowing fan at its peak. By tapping into the strength of the nocturnal thermal inversion, it sweeps the crop by propelling warm air above to the ground. Thus, stratification is momentarily suppressed. Furthermore, the continuous action of the machine, alone or in synergy, or the addition of a heater allow the bud to be bathed in a warmer environment. Also, the punctual action of the tower’s warm gust reaches the bud directly at each rotation period. All these actions allow the bud to continuously warm up, but with different intensities and over a different period. Although there is evidence of the effectiveness of the wind machines, the thermal transfers involved in those mechanisms raise questions about their true nature. Field measurements based on ultrasonic anemometers and fast responding thermocouples complemented by laboratory measurements on a reduced scale model allow to characterize both the airflow produced by the wind machine and the local temperature in its vicinity. Those experiments were realized in the vineyard of Quincy, in the framework of the SICTAG project. In the future paper, we will detail the aeraulic characterization of the wind machine and the thermal effects resulting from it and we will focus on how the wind machine warms up the local atmosphere and enables to reduce the freezing risk.

DOI:

Publication date: May 31, 2022

Issue: Terclim 2022

Type: Poster

Authors

Clara Le Cap1,2,3, Johan Carlier2, Hervé Quénol3, Dominique Heitz2 and Emmanuel Buisson1

1Weather Measures, Clermont-Ferrand, France
2INRAE, UR OPAALE, Rennes, France
3CNRS, UMR 6554 LETG, Université Rennes 2, Rennes, France

Contact the author

Keywords

spring frost, wind machine, thermal processes, vineyard, protection

Tags

IVES Conference Series | Terclim 2022

Citation

Related articles…

Les paysages viticoles des régions Vale Dos Vinhedos et Monte Belo (Brésil), un lien avec l’Etrurie

[lwp_divi_breadcrumbs home_text="IVES" use_before_icon="on" before_icon="||divi||400" module_id="publication-ariane" _builder_version="4.19.4" _module_preset="default" module_text_align="center" module_font_size="16px" text_orientation="center"...

Effect of terroir and winemaking protocol on the chemical and sensory profiles of Pinot Blanc wine

Wine research in the past years has mainly been focused on laboratory scale due to the possibility of controlling winemaking variables. Conversely, studies on wine quality in relation to the winemaking variables at the winery scale may be able to better account for the actual challenges encountered during wine production. Winemaking problems are recently arising from progressive changes in environmental conditions in relation to the terroir. It is important to realize that each wine region may have specific winemaking protocols and that winemakers often base their decisions on subjective, emotional, and empirical opinions. Due to all the above-mentioned issues, taking the correct decision in winemaking to achieve the desired goals may become even more challenging.

Dormancy conundrum: thermal requirements plasticity to reach budburst may be explained by annual environmental dynamics

Deciphering grapevine dormancy is crucial in the current context of climatic challenges: advancing budburst phenology and increased late frost probabilities, observed in the last decades and expected to further increase, require deeper understanding. Beyond higher mean temperatures, abiotic stresses such as water deficit have also been emphasized as actors. In this framework, we aimed at exploring new methodologies for tracking dormancy cycle and testing the interplay on its regulation of temperature dynamics and drought.
In a first experiment, twenty-one Vitis vinifera varieties were monitored during ecodormancy and budburst over three years.

Tasting soils in Pinot noir wines of the Willamette valley, Oregon

The conventional wisdom of vintners is that alkalinity, and thus less sour and more rounded taste, are enhanced in wine and grapes challenged by low-nutrient soils.

Multi-trait selection in ancient grapevine varieties

The selection of ancient grapevine varieties aims to achieve genetic gains in several important traits that can make the variety more interesting for the objectives of the producers. Traditionally, yield and quality traits of the must have been considered for selection, but many others can be taken into account. Linear mixed models are fitted to the data to predict the empirical best linear unbiased predictors (EBLUPs) of genotypic effects for each evaluated trait, which will be the basis for selection.