Who doesn't like to enjoy the beautiful warm and sunny days of summer? However, it must be recognized that in recent years, periods of heatwave have made summer particularly difficult to bear, and very hot weather sometimes spoils the holidays. Our organisms are not the only ones to suffer from rising temperatures, and winegrowers are noticing more or less clear changes in the vineyards of all wine-growing regions. Let's find out what impact global warming has on wine .
Global warming: what changes for the vine?
While everyone sees the effects of climate change on the planet, certain sectors of activity are more impacted than others. In the vineyards and in the cellars, climatic hazards have different impacts.
Earlier and earlier harvests
With the scorching summers that we have been experiencing in recent years, the first repercussions of such heat are seen during the development of the vines. As soon as spring arrives, the growth of the vine is rapid , and the first buds appear earlier and earlier. Unfortunately, during this period, periods of frost are still frequent, and endanger the vines.
Likewise, when summer arrives, flowering also occurs earlier in the year. If, in itself, this does not pose a problem either, this precocity also exposes the flowers to the risk of frost , which can compromise the entire annual wine production.
Finally, if the heat can be problematic, the major issue of global warming comes mainly from the lack of water in the vineyards , which causes intense and dangerous water stress for the vines.
If the buds and flowers resist the vagaries of the climate, the high heat then accelerates the ripening of the grapes, which pushes winegrowers to carry out early harvests . It is estimated that in 50 years, the harvest date has moved forward by one month.
More numerous and more resistant pests
The second problem of intense climatic conditions facing wine-growing regions is the increased risk of diseases and pests . Indeed, the hot climate is particularly conducive to the proliferation of certain species of vine pests, such as leafhoppers. Along the same lines, their behavior also changes, and they may prove more resistant to pesticides and have a longer life cycle.
Faced with this, the vine is weakened by heat and water stress , which makes it more vulnerable to increasingly tough parasites.
The drop in yield is one of the consequences of this scourge, but the quality of the harvest can also be reduced.
A modified taste of wine
According to several specialists, rising temperatures have a direct impact on the taste and characteristics of wines. We then see that the alcohol content and the sugar level are generally higher , and the acidity is less present. This is because the grape is more exposed to the sun, and therefore accumulates more sugar, which is then transformed into alcohol. In 20 years, the alcohol content of wines has increased by 2%.
Some experts have even noted that the numerous summer fires, linked to drought, can give a smoky taste to wine .
Countering the effects of global warming with new, more resistant grape varieties
To cope with these climatic disturbances, numerous experiments are underway to introduce grape varieties that are more resistant to heat and lack of water into the vineyards of France . Thus, several AOCs have received authorization from the National Institute of Origin and Quality to test 6 new grape varieties.
The process is likely to take time (15 years on average), because it requires numerous successive crossings before finding the perfectly resistant grape variety.
In the less long term, other experts are trying the use of rootstock , which consists of grafting a plant onto a vine, so that its roots go deeper and better capture water, to nourish the vine effectively.
Climate disruption: what solutions for the future?
We all know that global warming is the direct consequence of human practices and habits. We also understand that with some big efforts, it is possible to slow down this process. It is in this sense that the Paris agreement was adopted during COP 21. The objective of this international treaty, voted in December 2015 and applied in November 2016, is to massively reduce greenhouse gas emissions. greenhouse resulting from human activity.
On paper, we are asked to make sufficient efforts to ensure that the climate does not change too much, with temperatures rising by a maximum of 1.5°C by 2050 (compared to +2 to 2.5°C). for the darkest current prognoses).
In fact, this objective seems rather utopian, since it would amount to returning to a CO2 emission identical to that which we emitted in 1950. We must not forget that the population has multiplied by 3 since then, not to mention the he advent of many very polluting technologies which we would all have great difficulty doing without permanently.
Every gesture counts
Far from becoming defeatist, Man must above all become aware of his role in this mutation, even on a small scale. So, no gesture is superfluous to offer each French vineyard the most optimal production conditions possible.
In the vineyards too, the major players in the wine world are becoming increasingly involved, turning to organic farming . More environmentally friendly, organic wine producers use less invasive techniques, which both reduce CO2 production and help the vines better resist episodes of drought and heat.
Global warming is at the heart of current debates, and the source of many concerns. Winegrowers then try to find alternatives to help the proper development of their vines. It is in this sense that the Berne estate has decided to produce organic wines that respect the environment and the health of consumers.