Agricultural environment - Viticulture

IS THE CLIMATE CHANGING… or has it always changed?

To produce wine is like having a shop without a roof

10 October 2017

On August 7th at the Cudé vineyard in Traona (Valtellina, Sondrio), Davide and I observed the ripening progress to make necessary decisions.
The hardy terracing showed all its variability in terms of vines vigour, quantity and quality of grapes, degree of maturation, pathologies, and even nibbles made by birds.
When I find myself in such extraordinary places of heroic challenge that put man’s know-how against the mountain environment, my thoughts run fast, often landing on how our mission to produce a glass of wine can also be a lesson in life.
Over several decades, ‘climate change’ has become increasingly topical in both politics and our daily lexicon. More recently, “fans” from all fields with nothing better to do have come together to write about the subject. Thus I remember the old Milanese saying “Ofelè el el mesté” (“one should stick to what they know”) and I add, try to do better (pollute less, release less CO2 into the atmosphere…).
Polluting, producing high emissions, deforestation on a significant level, landslides or anything else that damages the environmental heritage is a criminal act and must be avoided. Changes in climate should remain the topic of scientists who can skilfully educate us, beginning with a reminder that our planet has experienced four hot stages in the last 10,000 years (studies by Umberto Monterin, 1937, “E’ mutato il clima sulle Alpi in epoca storica”?).

It is well known that in the Holocene period, our planet experienced four great warm phases, which were long ago named under the umbrella term “Climate Optimum”, in that they proved mostly favourable to human civilization. We refer in particular to the post-glacial Great Optimum, the Mycenaean Climate Optimum, the Roman Climate Optimum, and the Medieval Climate Optimum. The power and the global reach of such events, all before man significantly modified the atmospheric composition, is seen, for example, in the contents of O18 in the ice cores of Greenland (Alley, 2004; Dahl-Jensen et al., 1988). Temperatures for the centre of Greenland obtained from the GISP 2 ice core (Alley 2004). Data from 1910 to today has been obtained by subtracting 30.9°C from the average annual temperature of the Tasiilaq Coastal Station using the ECAD dataset.

Climate trends over the last 10,000 years

Climate trends over the last 10,000 years

Through research and critical examination, Monterin came to the conclusion that the great development of glacial masses in the 17th and early mid-19th century were the most significant to have occurred in recorded history. In the period prior to the 16th century, the climate on the Alps was milder and drier than in subsequent centuries, demonstrated by the following:

  • changes in the upper limit of the forest;
  • presence of a widespread network of high altitude water irrigation channels;
  • transit through now impracticable alpine passages;
  • glacier extension.

In the Challant Valley (Aosta), vineyards have been found at 1,300 mt a.s.l., while today the vine does not exceed 800 mt a.s.l. Thus all the natural facts indicate that the climate in the Alps has always changed and the last ‘little ice age’ ended just over 150 years ago, bringing with it a lot of suffering (let’s not forget the catastrophic epidemics written by our poet Alessandro Manzoni).
Following a priceless suggestion, I tried to immerse myself in a ‘climate archive’. So after staying overnight at Sils, Alta Engadine, I went to the Bernina valley, heading for Morteratsch. Here, following an easy path, you reach the valley of the same name, an excellent witness to the ‘little ice age’. Every year since 1878, the Morteratsch Glacier has been measured and its median/year shrinkage is 18m, although and in recent decades this value has increased.

Morteratsch Glacier

Morteratsch Glacier

Thanks to the fantastic information provided on location, I learned the highest part of the glacier reaches 3,900 mt and the ice tongue reaches up to 2,060 mt with a surface of 16 km2. The average thickness is 70 mt but there is a much thicker part, around 300 mt thick (to put it in fun terms, the glacier could encase the entire Eiffel Tower!).
This wonderful walk was crowned by views from the top and the flora (willows, larches, oaks, pine trees, rhododendron, mini juniper, which have bloomed in an area the glacier covered only 100 years earlier).

It was a journey towards the so called ‘thermometer of time’ that I recommend to anyone who wants to better understand and above all witness proof that nothing is static, everything is dynamic, above all the climate, which we must simply respect through our each and every action.

Back to the vineyard, it is commonly noted that 2017, a year without rainfall and above-average temperatures, has many similarities in some areas of Piedmont in 1947 (the following year, there was a flood), so it’s nothing new, although it is worth remembering certain behaviours that could help us. Other regions like Tuscany have experienced different difficulties in the vineyards and even in their olive groves. A lot of people, in particular those who are less ‘skilled’, harvested early as a result of various management shortcomings.

Climate trends follow cycles that are not known to us in advance, but the numerous sector research papers can help us a lot. It is admirable that we can follow extreme weather events well in advance (typhoons, thermal drops, the absence of rainfall). We must recognize that weather forecasts also have a big effect on viticulture (better crop choices, more accurate harvesting decisions…). And yet wine production, especially in some regions, does not always align with rational choices. Perhaps the greatest example of this is the cultivation of vine varieties in environments far removed from their origin. Management and training systems often expose productions to ‘definite risks’ and ‘less-than-perfect’ weather often becomes an alibi for failure.

Every historic viticultural area has a ‘statistical protocol’ of environmental characteristics that need to be known to improve, constantly… Climatic anomalies (for us) or exceptional situations are to be expected, but we still need to be more prepared and ready to demonstrate our foresight.

The vegetative cycle of the vineyard is quite complex and you can never learn enough. Every vintage is different and you can only make hypotheses of similarity with preceding vintages. But in this lies the strength of wine: it’s a watch and a library of our passage that we can ‘taste’ over time, reminiscing of memories.

Sunset towards Monviso mountain on 7th October 2017

Sunset towards Monviso mountain on 7th October 2017

The vintage of 2017 is still in the making, but it will surely be remembered in many European regions for these respects:

  • early sprouting caused by above average spring temperatures;
  • return of cold temperatures with widespread frost between 17 and 24 April;
  • extreme heat already in May and no rain leading to drought in many areas.

At the end of each season you can pull the sums, but in the meantime you learn, constantly remembering that a vineyard is like having a ‘shop without a roof’. Thus I must recall some useful steps and choices to increase the likelihood of better results. Of course, we refer to the areas historically apt for viticulture and therefore the main choices can be summarised as such:

  • choose varietals and biotopes that are historically cultivated in the territory. Italy has a huge stock of vines that are only partially being used. On the other hand, ‘international’ vines are frequently cultivated, extensively and throughout all regions, even though they are less adapted to drought and sensitive to certain pathologies and overly anticipated maturation, and therefore need considerable technological interventions and additives in the cellar. A commitment should be made to go ‘beyond the taste’ and communicate this to the consumer;
  • take care of the soil’s vitality and respect its functions and production potential;
  • avoid soil loss from compacting, erosion, spraying; protect it from the sun or heavy rain. Safeguard the preservation of organic matter, the true engine of every process. Restore the soil’s qualities, in particular with suitable vegetal material, brought or sown on site;
  • avoid cultivation at maximum slope (very common, for example, in ‘modern’ viticulture in Tuscany and beyond, after having ripped out the secular terracing).

The climate will continue in its variability, including, unfortunately, the much-feared hailstorms. We can only become better and more foresighted under the sky that gives us wonderful bunches, but often, at a steep price and not always: this is also an exercise in great patience. One choice is a must: to complain less, to avoid hasty judgments or the magical solutions offered by ‘professional’ salesmen, even if they are professors.

Climate changes have always existed and will continue in their dynamics. But since the beginning of the Industrial Age, human activity has produced environmental pollution and disorder. Among them, the growth of CO2 values in the atmosphere, which has risen exponentially. The agricultural and wine industries in particular also contribute significantly to CO2 increases in the atmosphere with very few people being aware. But this is a topic for further reflections.

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