In June 2007, the United Nations Climate Change Committee (Intergovernmental Panel on Climate Change) published the three-part UN climate report, on which around 2,500 researchers from 124 countries had worked for years. It is based, among other things, on around 40 computer simulations. It was agreed for the first time on a wording that people are to blame for climate change (but which is still disputed in some places). The highly developed countries are responsible for heating the atmosphere (global warming) and “exporting” the effects. The main causes are rapid population growth, increasing consumption of fossil fuels, deforestation and urbanization.
The relentless burning of fossil fuels such as gasoline, oil or coal creates huge amounts of additional carbon dioxide, the so-called greenhouse effect. In many regions of the world there has been a decrease in Frost days and an increase in days with extremely high temperatures was observed. This was particularly the case in Central and Northern Europe, the United States, Canada, China, Australia and New Zealand. In the central and northern latitudes, especially in the northern hemisphere, the frequency of heavy rainfall increased significantly in the second half of the 20th century. In contrast, in some regions of Africa and Asia there are increasingly stronger ones drought, as well as desertification.
Since industrialization, the average temperature has risen by +0.7 to +0.8 ° Celsius, with +0.6 ° Celsius alone in the past 30 years. Temperatures on Earth are likely to rise twice as fast by 2100 as in the previous century. Eleven of the past twelve years have been among the twelve warmest since records began in 1850. At best, the earth's surface warms by 1.1 to 2.9 degrees by 2100, at worst the temperature rises by 2, 4 to 6.4 degrees. A temperature rise of 1.8 to 4 degrees Celsius is predicted as the average warming. An increase in sea level of 18 to 38 centimeters was calculated for the most favorable scenario. In the worst case, it could rise up to 59 centimeters. Floods, crop failures and cyclones are increasing. About a fifth of the animal and plant species are threatened with extinction.
The climate has a significant impact on the vines and the wine quality. That is why climate change naturally affects the viniculture, although according to recent research results in the vine compared to other agricultural crops are assumed to be less. Records of climate values and wine-related data such as Vintage times. yield and quality of vintages has been in Europe for over a thousand years. During this period there were always fluctuations and also unusual conditions such as the Medieval warm period (900-1300) with average higher and the so-called Little ice age (1450-1850) with average lower temperatures. The causes and effects of today's climate change are far more dramatic, sustainable and faster. In the past, the major climate changes have been caused by natural phenomena such as global warming or cooling (ice ages) and have been very slow over many millennia. The current situation, however, is a reaction to man-made circumstances and is moving at an alarming rate.
Dr. Edgar Müller from DLR Rheinhessen-Nahe-Hunsrück is a profound expert on the subject and has written a lot of documentation on the subject. At the DLR location Bad Kreuznach (Nahe region) precise records have been available for a Riesling and a Müller-Thurgau parcel since 1959. Thereby were detailed phenological Data like expulsion. blossom. veraison and Vintage start detected. One of the findings is that the number of summer days (> 25 ° C) and hot days (> 30 ° C) increased dramatically in the period from 1959 to 2006. The average annual temperature rose by 1.0 ° Celsius. A large temperature surge can be seen particularly from the late 1980s. The following changes can be expected in southwestern Germany by 2050, although this will probably also apply to other Central European wine-growing regions:
Based on this, changes of different dimensions can be expected. These are shorter growth intervals, thicker vegetation with more leafy areas, higher water consumption and the necessary artificial ones irrigation, fluctuating yields, increased pest infestation and vine diseases and thus falling grape quality. Dry summers can result in a higher number of generations Grape berry moth and other insect pests, as well as common problems with bacteria. phytoplasmas and virus result. The impact on wine quality is therefore negative in the affected wine-growing regions. The white wines will have more alcohol and less acid due to their earlier maturity. This will be a problem especially for the Riesling that ripens late today, but also for the early ripening, low-acid varieties.
The frequency of UTA (atypical aging tone) and fermentation disorders will increase. This has negative effects on the aroma paired with phenolic Grades. In addition, there is less aging potential, So far only rampant diseases like in warm areas Pierce Disease could then also occur in Europe. The viticulture is bez. Weingarten Care and winemaking have to change or adapt. They are affected varieties, choice of documents, the fertilization, the training system in connection with the pruning, the question of greening, the plant protection as well as last but not least, that wine styles,
High-quality viticulture is possible in only a narrow geographical band, the so-called vine belts from the 40th to 50th northern and 30th to 40th southern latitude (see also under Rebstock ). The winegrowing areas in the northern hemisphere, near the equator and inland are more affected by climate change than those in the southern hemisphere, at high altitudes or near the coast. However, there will be global consequences for all wine-growing regions in different forms. Regions that are already dry and hot will probably have to deal with even bigger problems. In Australia and California a sharp decrease in precipitation is expected. Parts of southern Europe could become too hot for quality winegrowing. In the Champagne and in Bordeaux in turn, improvements through improved grape ripening are likely.
Better and new prospects are opening up for the previous climatic border locations. The wine-growing regions will expand towards the poles. Are in Europe Denmark. England. Croatia. Netherlands. Poland. Sweden and Ukraine Candidates. Outside of Europe Argentina. Australia (Parts) China (North), Chile and New Zealand, In a study published at the end of May 2008, the British wine trade company Berry Bros & Rudd sees China as the most important wine-growing country in the world in 50 years. The Middle Kingdom would not only be the most important wine-growing nation in terms of quantity, but would also keep up with Bordeaux in terms of quality. The big loser is said to be Australia as it would be too hot for quality viticulture in most areas.
Dr. Edgar Müller draws the following conclusion from this: Appropriate changes in cultivation technology as mentioned above can, in many ways, mitigate the effects of climatic changes. If the skeptical forecasts of the climate scientists are correct, our children, but at the latest our grandchildren, will practice viticulture that differs considerably from today's in terms of cultivation technology. This may apply. also for grape varieties and locations. Despite the considerable problems, German winegrowing would still be on the winning side compared to other large wine-growing regions in Europe today. The problems that we have in the house could be mastered. The prospects are much more bleak for large growing regions such as Central Spain, where viticulture is already reaching its limits due to a lack of water. However, the wine-growing problems of climate change would still be marginal compared to the possible global problems.
Nobody can say with certainty whether the optimists or the skeptics are right in the discussion about the expected changes. Everyone should know, however, that today's generation, out of responsibility towards future generations, should not afford the luxury of not doing nothing to let our grandchildren see who was right. They would probably have little understanding if the current climate protection options, such as energy savings or the expansion of alternative energies, are largely wasted because many people see them as an unreasonable financial burden or a restriction on personal development. If the skeptical prognoses came up, these restrictions or burdens would be ridiculous compared to the problems of our descendants (end of quote).
The congress created in 2006 Climate Change and Wine is dedicated to the problem area. With the threat to biodiversity from climate change, the term is often used biodiversity arose in the Organic viticulture plays an important role. The classification of the European winegrowing areas according to climatic conditions growing zones in relation to Weinbauwürdigkeit may have to change as a result of climate change. From the mid-1990s onwards (also) due to the fact of global climate change Cool climate winegrowing has become popular, which is understood to mean viticulture in higher areas with continental climatic conditions. See also under globalization and pollution,
Source: Dr. Edgar Müller from DLR Rheinhessen-Nahe-Hunsrück