The Heat is On – Climate Change and the Effects on Wine Producers

Climate change has already affected wine producers, and the challenges posed by rising temperatures and severe weather events are likely to increase. So how is the industry adapting?

Hurdles ahead

This year has been a good one for grape growers, producing a record vintage. But the previous two years saw reduced yields because of drought, fires and floods. And rising temperatures are an ongoing challenge to the wine industry. According to the Department of Agriculture, maximum and minimum temperatures are expected to keep rising across Australia, resulting in an average increase of between 0.6°C and 1.5°C by 2030.

What heat does

Grape quality can suffer when it’s too hot. If ripening starts too early, during the hottest part of the summer, the result can be a high sugar content, low acidity, and poor colour and flavour. High sugar means highly alcoholic, “big” wines. A warming climate is especially challenging for makers of the more delicate, lower alcohol varieties like Pinot and Riesling. The Australian Wine Research Institute has reported that grape harvests in Australia have started on average eight days earlier every decade since the 1980s. The harvest season has also been compressed, putting a strain on wine-making facilities.

Working smarter

Changing vineyard management practices are helping to counteract some of the effects of warming temperatures. One strategy is to change the time of pruning, which can delay the ripening of the fruit. Producers are also changing the orientation of the vines, planting on south-facing slopes, managing the leaf canopy to shade the grapes and even spraying with white clay as a sunscreen.

As it gets hotter and dryer, even growers who typically don’t irrigate may need to change their approach. For others, a switch to underground irrigation is helping conserve precious water. Wineries are expanding their fermentation capacity to handle more grapes, more quickly.

Going south

Many companies are buying vineyards in places with cooler climates, particularly in Tasmania, where the area planted to vines has been growing at around seven per cent a year since 2017. The growth in Tasmania has been in the premium wine sector, with pretty much every bottle retailing above $15. Prices for both Tassie grapes and wine are among the highest nationally as demand for quality “cool climate” wines increases. However, if the CSIRO’s projections of a 3℃ increase in temperatures by 2100 come to pass, Tasmanian vignerons may well be pulling out the pinot and replanting with shiraz.

Alternative grapes

One of the strategies producers are adopting is to embrace lesser-known grape varieties that are better suited to warm climates. Instead of the classic varieties of temperate France, these are grapes from Mediterranean countries including Spain, Italy and Greece. Producers in South Australia’s McLaren Vale have been leading the way, with Coriole planting their first Sangiovese in 1985.

Late ripening reds

Among the reds you’ll be seeing more of are Nero d’Avola and Aglianico. Nero’d’Avola hails from Sicily. It comes to maturity once the hottest part of summer is past and is less thirsty than other varieties. A medium-bodied red, it matches well with food, even spicy food.

Aglianico has its origins in Greece, but is now mostly grown in Italy where it’s sometimes called the “Barolo of the South”. Also late ripening, it can produce a full-bodied, complex wine with high acid and soft tannins, a great accompaniment to roast meats and a wine that will repay cellaring.

Climate tolerant whites

If you’re a Pinot Gris drinker, consider Vermentino. From Sardinia, it’s grown across a number of Australian regions including McLaren Vale, the Hunter and Central Victoria. Another late ripening variety, Vermentino has been described as having “notes of lime, almond, green apple, white florals” and “a unique sense of sea spray”. 

Coriole’s Mark Lloyd discovered Fiano in southern Italy in 2000 and produced the first Australian version in 2005. It’s now grown everywhere from Queensland’s Granite Belt to Margaret River and the Mornington Peninsula. Although there are different styles, many Fianos have lush flavours and aromas, high acidity and great structure – an alternative for the Chardy drinker, perhaps.