Climate Change Could Change the Taste of Kiwi Wine

NMIT viticulture tutor Dr Stewart Field

If temperatures, both above and below ground, keep getting warmer, Marlborough’s Sauvignon Blanc could lose its famed, distinct flavour.

It won’t change any time soon, however. Bragato Research Institute viticulture extension and research manager Leb Ibbotson said the wine industry had already started adapting to warmer seasons.

“There’s a certain amount that we can do from a viticulture and winemaking perspective to buffer those changes,” Ibbotson said.

“We’ve had a run of really warm seasons in Marlborough, much warmer than the long-term average, and we haven’t seen a dramatic shift in wine style.”

Ibbotson said these tools included harvesting earlier or blending with subregions planted in cooler climates.

“That works for now, will it work in 20 years or 30 years? That’s all going to depend on how severe those changes might be,” he said.

“Over time that might require that we take a different approach to how we grow.”

The Marlborough District Council commissioned Niwa to research projections and potential impacts of climate change for the region, with the findings released last month.

Niwa’s report projected average maximum temperatures to increase up to 3 degrees Celsius by 2090. The average number of “hot days” (over 25C) was expected to increase, with up to 65 more by 2090. Frosts were expected to decrease, and there could be more extreme, rare rainfall events.

“As a result, changes to Marlborough’s (diurnal) temperature range may alter the characteristics of the grapes grown in the region,” the report said.

Nelson Marlborough Institute of Technology viticulture tutor Dr Stewart Field recently won an award from the American Society for Enology and Viticulture for his grapevine soil research alongside co-authors from Charles Sturt​ University in Australia and Trent University in Canada.

The research was conducted to understand how soil temperatures affected grapevine growth – a subject linked to climate change. The research concluded soil temperature significantly affected grapevine growth, as colder temperatures took carbohydrates into their roots “like storage”.

Field thought more research would need to be undertaken in order to better understand how climate change would affect the industry.

“I think the temperature definitely will have an effect,” he said.

“Probably the loss of the green flavours, on warmer years we’re losing those. Unless there are some vineyard management techniques that you can use to combat that.”

The full NIWA climate change report could be found on the Marlborough District Council website.