Frost in Europe and Australia
Despite a temperate climate, Europe and Australia (more prevalent in the East Coast’s major wine regions) have suffered from severe and frequent frost events in recent years.
The buds, shoots, leaves, and flowers of the vines were all damaged, while the yield and quality of the wine grapes reduced. The frost events have been caused by the combination of low temperatures, clear skies, calm winds, and high humidity, which have been influenced by the effects of climate change, such as the polar vortex weakening, the shifting jet stream, and the El Niño and La Niña phenomena.
The frost events have had negative impacts on the economic, social, and environmental aspects of the wine industry, such as increased production costs, lower revenues, higher prices, lower competitiveness, reduced employment, lower biodiversity, and higher greenhouse gas emissions.
The frost events have had negative impacts on the economic, social, and environmental aspects of the wine industry.
Frost in the UK and New Zealand
Frost is also an issue affecting vineyards in the UK and New Zealand. During spring, water in the vines can freeze and expand its tissues, posing a threat to the growth of new buds, shoots, leaves, and flowers. Grapes that make two of the most popular wines, Chardonnay and Pinot Noir, bud early, so they are particularly affected by below zero temperatures during spring.
Mitigating against frost events
To cope with frost events, the wine industry in Europe and Australia has adopted various protection and adaptation measures, such as:
- Using heaters, wind machines, frost sensors, sprinklers, helicopters, candles, or antifreeze proteins
- Selecting frost-resistant and early ripening grape varieties and rootstocks
- Modifying the pruning and training systems
- Applying frost alarms and forecasts
- Diversifying the income sources
- Relocating or abandoning the vineyards
While the UK government have deployed practical measures such as frost candles and provided funding to the industry, the rest of Europe and Australia have taken extra measures. Associated organisations have discussed the uses of adding heat from off site to protect the irrigation process as well as using heat in the atmosphere to mix warm and cold air (often conducted using helicopters).
However, some of the challenges the wine industry faces in implementing these measures include the high costs, low effectiveness, limited availability, environmental impacts, and legal restrictions of some frost protection methods. There is also uncertainty and variability of the future frost occurrences and the climate change impacts.
