An insider's guide to climate

Climate (specifically, climate change) is a hot topic globally, particularly within the agricultural sector. It’s particularly poignant in Australia, which has a vast range of climates – warm, temperate, cool, cold, inland, coastal – plus many micro-climates within those.

What and where we can grow is changing, with positive and negative effect. Grape farmers, like all farmers, have always been at the mercy of the seasons, and understanding climate is all part of the job. Here, we’ll look at some of the key factors.

What is climate?

Climate is different than weather. Weather refers to the variation between each day, week or, in the case of the wine industry, the vintage. Climate refers to the long-term average of weather patterns in a specific region over an extended period.

Cause and effect

It is important to consider that climate can determine style, but it shouldn’t determine quality. It’s possible to make wine in almost any climate, so long as the site is a good match for the variety planted and the winemaking is mindful of these variables. That said, most suitable climates are found between 30° and 50° latitude, both north and south.

Site selection

Viticulturists think just as carefully about what to plant as where to plant it. There’s soil type to consider, the aspect, and potential for inclement weather. The choice of variety and resulting wine, however, are heavily influenced by climate.

Pinot noir, for example, grows best in cooler conditions. Rising temperatures are shifting not only where pinot noir can grow, but where it grows well. For this reason, Champagne houses are buying up vineyards in the UK, while the once too-cool Upper Yarra is fast becoming one of Victoria’s top pinot growing areas.

Some varieties are more adaptable than others, with climate influencing the finished product. Cool-climate shiraz (syrah) is medium- to fullbodied with a complex spice profile, medium-fine tannins and good fruit density. Meanwhile, warm climate shiraz has higher alcohol with rich, ripe fruit flavours and tannins that can be astringent in youth (but can age for decades). It’s simply a matter of preference.

Future proofing

Winemakers are increasingly turning to ‘climate appropriate’ varieties to mitigate the effects of climate change. For many, that means planting thick-skinned, sun-tolerant grapes that don’t require irrigation.

Varieties that are indigenous to warmer, drier regions tend to do well in other warm, dry regions. That’s why we’ve seen an uptick in the likes of vermentino, nero d’Avola and montepulciano on these shores. The latest is nerello mascalese, native to Mount Etna in Sicily, for which Chalmers’ nursery already has a waiting list, to quote Kim Chalmers, “as long as your arm.” ●