Shifting sands of wine production

New Zealand winegrowers need to factor climate change into their forecasts. Photo / Supplied

The traditional wine growing areas are on the move – thanks to climate change.

When pioneering vintners planted sauvignon blanc in Marlborough, they knew it was a cooler climate than where it was traditionally grown in Europe. The experiment paid off, with a distinct New Zealand style winning favour around the world.

But Glen Creasy, the senior lecturer in viticulture at Lincoln University and also the president of the New Zealand Society for Viticulture and Oenology, says climate change means a lot of grape growing regions are becoming warmer. Winemakers will not be able to make the same styles or even varieties of wines they have made in the past.

It's an international problem. A paper published last year in the US Proceedings of the National Academy of Sciences predicted that area suitable for viticulture could shrink by up to 73 per cent in some major wine producing regions. Other areas, especially at higher elevations or in coastal regions, could be substituted.

Some champagne houses are already buying up land in southern England, where the white cliffs of Dover have a similar chalky soil to that in the Champagne region.

The study estimated the area in New Zealand suitable for viticulture could more than double. Creasy says growers are planting further up the Wairau valley than they would have considered 20 years ago, as well as moving east into the Awatere Valley and around Ward, where temperatures are kept lower by the easterly wind blowing off the sea.

"Areas that are too cool to grow quality wine now will, in the future, be able to grow quality wine. We may find in 50 to 80 years that most of the Marlborough Sauvignon Blanc is being made in Ward and not the Wairau Valley," he says.

The land east of Martinborough and Masterton and more of Canterbury may also become planted out. "We will find ways to adapt. No one wants to give up on the wine industry. It is a big earner for the country."

People are planting varieties like viognier, which likes it hotter, and syrah and cabernet could come into their own. "There are people experimenting with Grüner Veltliner, which is a grape variety from Austria. It's grown in a cooler climate there, but it's an opportunity to define new wine styles people may like," Creasy says.

Harvesting may be done earlier, as has been happening gradually in Australia over the past couple of decades. Growing methods may change, for example by not removing as many leaves from vines during the growing season.

"The biggest issue is with the frequency of extreme weather events. Late frosts might happen less frequently but when they come they are worse in terms of cold and coming later in the year," Creasy says.

Hawke's Bay growers still shudder to remember the devastating November frost a decade ago that burnt the fresh growth on their vines, and a lot of New Zealand is susceptible to similar events. "Like any other farmers, grape growers try to mitigate risk. They may need to invest in frost fans where they never had frost fans before, or they may need to keep tabs of the seasonal weather patterns and change their management response rather than assuming this year will be like last year."

The Climate Change Solutions series is a joint project between Element and Lincoln University, which is intended to illuminate a pathway for a sustainable future.