Good prospects for wine produced in Denmark

The changes in our climate have improved conditions for wine growing in Denmark. Over the past decade, the amount of land under vine in Denmark has doubled due to rising temperatures.

The prerequisite for wine growing is that wine of adequate quality can be produced in sufficient quantities. The quality of a wine is determined by a wide range of factors, including the variety of grape, stock, soil type, climate and cultivation technique. Traditionally, the production of wine in Europe has been determined by a combination of soil and climate. These two factors form the basis for the term "terroir", which indicates the potential for wine growing in a particular region. Whereas the soil provides a constant basis for wine production, the weather varies from year to year and this leads to fluctuations in the quantity and quality of the wines produced.

Wine production is limited to regions in which the climate is conducive to growing grapes with a balanced composition of sugar and acid, which reflects both the region and the variety of grape. There are three main climatic conditions that must be met in order to produce wine of high quality:

Stocks are resistant to summer drought, provided the soil allows sufficiently deep root development, and dry weather during harvesting is an advantage, as it ensures just the right concentration of sugar and prevents disease in the plants.

Wine's sensitivity to climate change
The global rise in temperature in recent decades has generally led to an improvement in the quality of wine in Europe. This is mostly due to rising temperatures during the growing season, which has affected the quality of the grapes in several ways. Grapes begin to grow during the spring when the temperature has been above 10°C for a length of time. The earlier and warmer the spring, the longer the growing period of the grapes, which increases the quantity and improves the quality of the wine. High temperatures during the maturation period result in the formation of tannins, sugar and flavourings in the grapes. These also improve the quality of the wine in regions with cool climates.

Development in Danish land under vine from 2005 to 2010
Only grape varieties that are able to withstand cold winters and can cope with a relatively short and cool summer are grown in Denmark. However, the warming of the climate has made it possible to grow grapes in Denmark and achieve both a reasonable yield and acceptable quality. As a result, the area of land under vine increased by around 5 hectares a year between 2005 and 2010. Thus, the area more than doubled during the period (Figure 1). Similarly, Figure 1 shows that the number of businesses producing wine also doubled during the period. 


Figure 1. Trend in Danish land under vine from 2005 to 2010.

The rise in temperature is also obvious when we look at the regional trends in land under vine in Denmark. In 2005, 88% of the land under vine was located in the three southernmost regions (southern Denmark, the Capital Region of Denmark and Zealand), with the majority on the island of Zealand (Figure 2). Central Jutland and northern Jutland accounted for a mere 12% of the land. By 2010, this figure had risen to 28%. The increase primarily occurred in central Jutland. However, even the regions that already have wine production, such as Zealand, are showing a sharp increase in land under vine, cf. figure 2.

Figure 2. Land under vine between 2005 and 2010, in hectares and by region.

Chardonnay du Næstved in the future?
Aarhus University has investigated the way in which growing conditions for the Chardonnay grape will develop in Europe between now and 2040. Climatic requirements for growing crops are summarised in a temperature index, which indicates the number of thermal units that must be accumulated during a growing season for a crop to reach maturity.
The so-called Huglin Heliothermal Index is used to indicate whether conditions are suitable for producing wine. Calculations are based on climate forecasts for 2020 and 2040, produced using six different climate models.

The area suitable for growing the Chardonnay grape is moving north in Europe. However, according to the calculations, these grapes will not be suitable for cultivation in Denmark in 2040. It was decided here to focus on Chardonnay grapes with a relatively low heat requirement (1700 Huglin units). A grape such as the Syrah has a higher heat requirement, 2100 thermal units, and will therefore be more difficult to grow. However, it is important to emphasise that all calculations were made based on an average climate in relatively large areas. This means that, for all crops, there may be many localities within the areas studied (south-facing slopes and similar warm pockets) where conditions for growing grapes would be favourable.