Climate Witness: Johann Schnell, Germany
A switch to organic farming
30 years ago my father decided to change his winery into an organically run cultivation. He collected butterflies and he noticed in 1970, when the first strong pesticides were marketed, that the variety of species of butterflies found in the vineyard was reduced tremendously in a very short time. He decided then, that the path chosen by many other winemakers and farmers — away from nature, to pesticides and fertilizers — would not be his path. We view the vineyard as part of the ecosystem. Organically made wine is a sign of quality these days. It gives the last finishing touches to the wine, the final character. This is not achievable with conventional cultivation.
I have dealt with climate changes since I started growing grapes. There were years with very strong frosts, sometimes even as long as into May. Change in climate has always been an issue for us. However, the current changes are of a different nature. It has become obviously warmer.
Recording the weather
A wine maker is obliged to make exact notes about the time of harvesting and the "Oechlsegrad". This is the sugar content of the grape juice, which is responsible for the alcohol content of the wine. Through these measurements it is very easy to observe the changes in climate in our region. Due to longer warm periods, particularly higher temperatures at night during autumn, the timeframe in which the grape stores sugar has become longer. This is why the alcohol content has risen. Our notes started in 1974. We have been measuring notably higher values since 1998-99 when I took over the estate. In the beginning we thought those years might be exceptions. Since 2003 the measurements have not returned to previous levels. These days we have alcohol contents of 13-14 %. When my father started out as a winegrower those values were utopian and could only be reached in exceptional summers such as in 1976. The exception has become the rule now.
The time of harvesting has changed to two weeks earlier. In former times, winegrowers pondered how to get the most sugar into the grape. These days the question is different: when is the grape physiological ripe, without having stored too much sugar, so as not to give too much alcohol content to the wine? These days we are having an abnormal situation. We have to harvest at times when the "Oechlsegrad" is not too high. A high sugar content is not favourable for the white wines as we know and like them. That is one reason why there are mainly only red wines in the Mediterranean countries.
Increased viruses and fungi
We also fight more fungi and viral illnesses these days. We have found species of Cicadas which were in former times only found in Mediterranean areas. These infect our vines with viruses which some are very susceptible to. The virus has a devastating effect on the vine. Vines that just began to sprout will die off within one week. Each year about one to two percent of vines die off per vineyard, and this trend is increasing.
There are also certain fungal infections, which occur suddenly, with the effect of killing healthy vine. Another example is "black-spot" which causes the grapes to go bad. The increase of such fungal infections in the last years is due to warmer nights in late summer and autumn. The warmer it is, the shorter is the time needed to infect vine by fungal infections.
The only way we can deal with the fungal infections is to replant the vine. However, this is not a long term solution. At some stage it will not be worth it any more to plant certain special vines. One way to fight fungal infections in an ecological way is by keeping the vine loosely planted to keep good ventilation through the vine. This requires lots of manual labour by picking leaves of the grape zone and cutting out grapes if they hang to close to each other. We also have to spray more. Of course we use ecological means, mainly copper and sulphur. In the future, unfortunately, I will be forced to plant vines that are more resistant to fungal infections and does not need spraying any more, such as Johanniter for white wine and Regent for red wine.
One strategy to reduce the high alcohol content would theoretically be the technical de-alcoholising which is a common method used in the new World. In Germany, luckily, this method is not permitted, but is under discussion. Being an organic farmer this is not an option for me. This is a fundamental principle. In the perspective of climate change, it seems senseless, to me, to invent new technical strategies to continue the way we have always had.
For us organic winemakers the water shortage, particularly in spring, makes it difficult to plant vegetation among the wines. We used to let plants and wine grow next to each other at the same time in spring. These days plants and wine compete for the little water there is. This is the reason why we sow Rapeseed in winter, which later turns into organic fertilizer for the wine. However, this problem is still manageable. For many conventional winemakers the shortage of water implies less return. This is a particular problem for those who always look for the maximum return. Germany has the highest returns per hectare in all of Europe. This can only be reached by maximal cultivation, or high rainfall, or watering.
Winemaking will persist and not vanish. One can grow wine grapes also in Australia, for example. We will have to grow different sorts of wine grape and our wines will change There are wine grapes around of which we have a certain and clear idea. One example for this is our Riesling, a typical wine not only for this region but also for Germany. This particular wine changes its taste markedly. It will have less acid but more alcohol with a fruity, strong aroma. The question is if the customer likes these changes to the taste. It is also doubtful if we are able to continue to grow this grape for much longer, due to the increasing incidence of viral illnesses.
A global issue
Of course, agriculture and wine growing are used to changes in climate. One always needs to adapt. However, we shall not forget, that the changes I have noticed in my vineyard are only signs of a much bigger, more global problem. It has a much bigger implication to lots of other people and cultures. In this part of Germany we are quite protected from raising sea levels. Bangladesh is not. It is everyones' responsibility to do something against climate change. It is everyones fault, even if it has less implication for our country than for other countries.
Minimising energy use
We have kept mechanism as sparse as possible. This means we still harvest by hand and I work with as few and as little machines, with small horse power, as possible. We have power solar panels on the roof and have exchanged our oil heater for a wood-pellet heater. On the estate we still use wooden barrels and recycled glass for the wine bottling. Many winemakers do not care, since new glass is still so cheap. The reason for this is that energy is still so cheap. We try to work energy efficiently in every way we possibly can on our estate.