Though the British wine industry appears to be booming as the effects of climate change become more apparent, and the government has recently announced its support for growing production, new research suggests that the future may not be quite so rosé for British wines, as cold snaps, sharp frosts and downpours still threaten productivity.

UK wine producers hope 2016 will be a bumper season, but research from the University of East Anglia suggests year-to-year climate variability and hazardous weather at key points in the growing season - arising as a result of human-driven climate change - are likely to leave the industry highly sensitive to the elements.

The research also suggests that in vogue varieties such as Chardonnay and Pinot noir are more susceptible to UK climate variability than traditional varieties.

Over the last decade there has been a boom in English wine production. The amount of land used for viticulture has increased by 148 per cent - with around 1884 hectares currently under vine. Last month, after a meeting between Defra officials and wine industry representatives, environment secretary Liz Truss announced plans to grow Britain's wine industry. The meeting ended in an agreement to double wine production in Britain by 2020.

Shortly afterwards, NASA scientists confirmed that climate change is causing a shift in wine production, bringing earlier harvests, though not necessarily better wine. The scientists said that their research, based on over 400 years of data from across France, supports findings that show wine production may have to shift northwards to cope with the effects of climate change, as southern regions become less suited to growing certain grape varieties.

Assessment weighs up threats and opportunities

Researchers from UEA studied the UK's main grape-growing regions and looked at the relationships between temperature, rainfall, extreme weather events and yield. They also surveyed wine producers for their views on the role of climate change in the success of English wine.

By combining this data, they were able to identify opportunities and threats to the industry for the first time.

Lead researcher Alistair Nesbitt, from UEA's School of Environmental Sciences, said, "The UK has been warming faster than the global average since 1960 and eight of the warmest years in the last century have occurred since 2002. Producers recognised the contribution of climate change to the sectors recent growth, but also expressed concerns about threats posed by changing conditions"

"We wanted to see whether potential future climate change may make wine-making more viable in the UK by first analysing sensitivity to past climate variability. We found that while average temperatures over the growing season have been above a key minimum threshold for 'cool-climate' viticulture for two decades, wine yields vary considerably."

The research revealed that June rainfall is the key indicator, explaining year-to-year variability in grape yields in the UK. South and South-East England - the key wine growing areas of the UK - are still subject to weather variations and extreme events, with late frosts taking a particular toll, and a move towards Chardonnay and Pinot noir has left producers more susceptible to the vagaries of weather.

The South-East is set to experience more water shortages than the rest of England over the course of the century, and shifting rainfall patterns are expected to see the UK experiencing more rainfall, but in fewer, heavier downpours.

UEA’s Alistair Nesbitt explained, "High quality wine grapes grow best with an average growing season temperature in the range of 13-21oC. But even within this range, there are other factors at play.

"Since 1993, the average southern England growing season temperature has consistently been above 13oC and since 1989 there have been 10 years where the temperature was 14oC or higher (up to 2013). This is around the same temperature as the sparkling wine producing region in Champagne during the 1960s, 70s and 80s.

"However by comparison, UK wine yields are very low. In Champagne, yields can be more than 10,000 litres per hectare, but in the UK, it is around 2,100 on average. While rising average temperatures are important, the impact of short term weather events such as cold snaps, sharp frosts, and downpours will continue to threaten productivity."

Looking to the past, Nesbitt said bumper years (1996, 2006 and 2010) can be linked to optimum temperatures and weather conditions - warm springs and autumns and the absence of frosts at critical times. Meanwhile low yielding years (1997, 2007, 2008 and 2012) are attributed to wet and cold weather during flowering, wet and cold growing seasons, low levels of sunlight, poor summers and/or spring frosts.

Nesbitt added, ”We found that the spring months of April and May have become warmer over the last 25 years. This is a significant time when buds burst and initial shoot growth takes place. Warmer temperatures at this time indicate an earlier start and lengthening of the season.

"However, when warmer temperatures occur in April there is potential for increased vulnerability if a May air frost follows."

"In June, wet weather, particularly when combined with cool and overcast conditions, can really impact the flowering process, delaying it and reducing the number of berries and young grapes forming on the vines. We saw a correlation between high June rainfall and poor yield across the whole period we studied."

"A recent change in dominant UK vine varieties has also increased the industry's sensitivity to weather variability. There has been a drive to produce English sparkling wines such as Chardonnay and Pinot noir - but these grapes are more sensitive to our climate variability."

"It's too early to predict what the weather may hold in store for the 2016 growing season, but a warm spring with low frost levels would be the promising start producers are hoping for.”