Climate Change, Global Warming & Wine Production

The wines we know today are grown in areas with a relatively stable climate, where grapes and methods are adapted to this. If the global warming continues and we see increasing temperatures in the same degree as now, then it will have an affect to which grapes can be grown where. The wines grown under the current conditions will probably be more sought after than they are today. Below you can get a better idea of what the climate changes mean for the wine you have in the glass.

How Climate Change Affect Wine

Climate change is indisputable, and not least global warming. It certainly has a great influence on the production of wine in the classic areas. It can be anything from changing rainfall patterns to hail and frost later in the season.

For example, in recent years hailstorms have been seen destroying grapes and vines in Burgundy, Piedmont, and Bordeaux. There are many indications that the weather will also be more extreme in the future and this is the kind of challenges winegrowers face these years.

What vine's need to produce grapes:

• A lot of sun and heat give sugar in the grapes, which are converted into alcohol.
• A long growing season provides an optimal build-up of flavor complexity in the grapes.
• The right amount of sun over a long period of time, provides the right balance between sugar and acidity in the grapes.
• The right amount of water causes the vine to grow without drowning.
• Colder temperature than normal will lead to wines with higher acidity, lower sugar, and unripe flavor aromas.
• Warmer temperatures than normal will lead to wines with lower acidity, higher sugar, and overripe cooked fruit aromas.

With this in mind, it is obvious that climate change presents the winemakers with a lot of challenges. Rising temperatures in most European wine regions have forced producers to consider everything from grape varieties to pruning.

Grape Varieties, Clones And Rootstocks

It is essential to have a closer look at the vine to better understand the choices and opportunities the winemaker faces. The vine is part of the Vitis genus, which has several different species. The species we know best is Vitis Vinifera. In this species, we find all the grape varieties we know from wine production, everything from Riesling to Syrah. The different grape varieties depend on different amounts of heat, light, water, and nutrients from the soil. They will of course be planted in different climates and with different outcomes as a result.

Associated with the concept of grape varieties, winemakers will also focus seriously on the sub-division to clones. A clone is a development of a grape variety, so it becomes even stronger. A clone can develop naturally in the field as a mutation of the variety, or it can be cultivated.
What the winemaker must consider is that one clone can provide quantity and another clone of the same variety can give more black fruit aromas.

Often the winemaker will choose clone, or clones, depending on the type of wine he wants to produce in the terroir he has available. Certain clones are more resistant to warmer temperatures than others. Within a grape variety such as Pinot Noir, there are clones that can withstand the heat in California and those that can ripen in cooler climates like Germany.

Once the grape variety and clone are selected, the winemaker must also select the rootstock of the vine. In the 1860s, the wine pest Phylloxera came to France. It is an insect that attacks the roots of Vitis Vinifera plants. When winemakers realized the pest came from the USA, one could find roots that were resistant to the insect. In the United States, they work with other species, including table grapes, which are not of the Vitis Vinifera genus.

The two best known are Vitis Labrusca and Vitis Riparia. These variations have proven resistant to Phylloxera wine pest, which is why they chose to graft the old varieties on top of the American rootstocks. In fact, it is the reason why European vineyards are alive to this day. Since then, the wine pest Phylloxera has spread to most of the world, so it is normal to use American roots and traditional Vitis Vinifera varieties on top.

What Options Do The Winemaker Have To Fight Climate Change?

In a climate context, this becomes particularly interesting because the winegrowers have learned to distinguish between the different rootstocks and their adaptability. Today, winegrowers know which rootstocks can handle more or less moisture in air and soil to supply a sufficient number of grapes. Certain varieties are more resistant when it gets warmer and others more resistant to plant diseases.

So, on basis of all this, the winemakers must choose the right grape varieties, clones of these, as well as the right rootstocks. These choices must be made by the winegrowers based on the conditions prevailing in their area today as well as based on the climate change that they foresee in the coming years.

These are just some of the obstacles that the winegrowers face on a day to day basis. Another thing they can consider in short terms is the canopy control, where they control the leafs around the grapes. A lot of sun is good when needed, but too much sun can also be bad.

Sunburn And Wild Fires
In the past years during the growing season, Burgundy has seen rising temperatures and an increase in the number of hours with sunshine. During a visit to the cult producer Christophe Roumier, Christophe said that 1998 was the first year in which they experienced sunburn on the grapes. From this year they had to consider how much leaf foliage they had to keep for shading. Previously, all leaves had been removed so that the grapes could get as much sun as possible. Today, the leaves are pruned to cover the grapes, to avoid getting too much sun.

No one can predict the future, but a likely scenario is that many grape varieties will move a good distance further away from the Equator than what we have gotten used to if the temperature continues to rise.

It will also be interesting to see what California will look like in terms of wine production. These years they are fighting wildfires almost every year, which destroys both vineyards, wineries, and homes.