Italy, climate: Longitude and latitude play a role in creating different micro-climates and vineyard habitats. Italy lies between the 47th and 45th parallels, roughly corre- sponding, in the north, to the vineyards of central France, and, in the south, to those of southern Spain and northern Africa. The climate is mostly temperate thanks to the thermoregulating effect of the Mediterrenean sea, though vineyards are culti- vated in all sorts of weather conditions, from the extremely hot areas of the south to very cold areas in the Alps. In addition to the continental South, Italy is also surrounded by archipelagos of small islands that are closer to Africa than to the mainland, for instance Pantelleria and Lampedusa. Clearly, having hot days and cold nights is an asset, and Italian vineyards are for the most part planted where noteworthy day-night temperature excursions exist—this excursion being an es- sential condition to the formation of aromatic precursor molecules that give wines characterized by greater intensity of perfume. At times, for example in some vintages such as 1997 and especially 2003, the heat can become too strong even in areas which are not normally very hot, e.g. Piedmont and Tuscany, and over-ripe fruit becomes characteristic of the vintage. Overipeness is never a good thing, for wines made with such grapes show cooked aromas and flavors, and can be quite jammy on the palate. Clearly, these wines are anything but refined or graceful, and though showy at first, are not likely to be very ageworthy, because of likely lower-than-average total acidity.
Almost always, Italy’s climate is such that without reaching the extremes of 2003, nobody has any trouble ripening grapes, because there are enough growth-degree days for grapes to grow well. Growth degree days, or GDD, is a measure of heat accumulation that tells us if grapevines are metabolically active; at below 10°C, grapevines are not, so little happens in the berries. By adding up the temperature values each day from April 1 to September 30 in which grapevines are metabolically active, a total number is obtained that indicates how likely it is that the area will be ideal for viticulture. In cool climate, Champagne for example, GDD may be less than 900, while it is well over 1400 in a much warmer Napa valley. For the most part, Italy’s viticultural areas all fall in between these two extremes. Further proof that grapes ripen without much difficulty in Italy lies with the law that prohibits chaptalization, that process devised by a French government minister Jean-Antoine-Claude Chaptal, from whom the name of the process was derived, where sugar is added to fermenting grape juice (or must) in order to increase the final alcohol content of the wine. Of course, this is because wine is the end result of the biological process in which yeasts break down naturally occurring grape sugars, turning them into alcohol and carbon dioxide.
In France, where it is much colder, chaptalization is both legal and heavily practiced, even in those regions such as Burgundy known to the world for expen- sive wines. Unfortunately, while Italy does not allow chaptalization, it does allow the use of concentrated must, which is not necessarily better than chaptalizing. Actu- ally, it can be much worse if the must that was concentrated in the first place was not very good to begin with. Warmer average temperatures are just another aspect of Italy’s fortunate situation relative to grape growing, though climate change is starting to have an impact on Italy as well. For example, many storied vineyard sites, which have became famous because they allowed grapes to ripen fully in times less challenged by global climate change, are now producing less-memo- rable wines in the hottest years. What was once a very desired characteristic, i.e. a southern exposure, may not be so today, and in fact, many new vineyards are being planted with northern exposures, especially in hotter regions of Italy’s south (but not just there!).
Clearly, matters in the making of fine wines are more complex than just having a bevy of sites that are favored with great geological features or exception- ally well-suited microclimates. And though temperature is the most important factor controlling rate of plant development, other all-important parameters exist as well, such as water and light availability, daylight length, wind strength, and exposure, all of which may modify its effects. The work of human beings is also all important. For instance, it changes things considerably for the grapes if men and women who work in the vineyard decide to use a canopy trellising system (with lots of foliage to shade the berries) or a cordon spur one (in which grapes are much more exposed to the sun’s rays). Happily, Italy is not shy in total number of sunlight hours, and thanks to its mountainous personality, the country is loaded with streams and riv- ers, so water availability is rarely a problem. In fact, irrigation is allowed only in spe- cific cases and few areas of the country, and then only as a supportive measure.
Therefore, it should appear evident that differences in factors such as al- titude, exposure, soil composition, and micro-climate will lead to the final wines of very different quality levels and very diverse personalities. See for yourself: try a Pinot Grigio wine made from grapes grown on the outstanding, high quality river bed plains of the Isonzo river in the region of Friuli Venezia Giulia (one of the very rare high-quality flatland vineyard areas of the world) and discover how this will yield a very different result than a wine obtained with the same grape variety grown high up in the mountains somewhere else (e.g.Valle d’Aosta’s Pinot Grigio).
See Ian D’Agata, Native Wine Grapes of Italy (University of California Press, 2014).
Italian Wine Unplugged (Positive Press, 2017), p.20-21.
Italian Wine Unplugged (Positive Press, 2017), p.21-22.