You hear wine buffs talking about the Central Otago Continental Climate. So what is exactly is this and what are the wine growing climates?
The climate of a region has significant impact on the choices made by the viticulturist in a region. Of course the micro-climate of the actual vineyard is of the most importance but when we talk in broad regional terms we are actually referring to the overall climate.
The classifications of climates are based broadly on a scale called the Koppen climate classification: being Tropical, Oceanic, Mediterranean, Maritime and Continental. In general however wine is only grown in the three temperate climates (Mediterranean, Maritime and Continental). Our climate in Central Otago strictly falls into the Oceanic classification but only marginally and so we refer to as a Continental wine growing climate.
The Mediterranean Climate
Areas such as Tuscany are referred to as having Mediterranean climates. Their temperatures are relatively stable year round with winters being generally warmer than maritime and continental regions. The growing season tends to be very long with very little rain.
The Maritime Climate
Most of New Zealand wine regions are classified as maritime climates given their proximity to the sea. Like with the Mediterranean climate the water moderates temperatures both from night and day and over the long growing season, but maritime wine growing regions also have distinct seasons like the continental regions albeit less extreme. However, the water also carries with it increased risk of too much rain and humidity which can cause fungal diseases like cold and mildew on the grapes.
The Continental Climate
Central Otago is typical of a continental climate – large temperature differences not just between seasons (Central Otago is very hot in the summer and cold with snow in the winter) but also between night and day. With the extreme winter cold grapes grown in continental climates risk damage from frost in spring and autumn. Continental climates usually have less annual rainfall than the other climates. Central Otago is New Zealand only true Continental Climate.