Climate Change and Nova Scotia sparkling
I was recently asked to sit on a panel about the effects of climate change to the Nova Scotia wine industry. This request adds to a significant increase in focus lately - there are new research proposals on how vineyards can be more resilience, trade conferences like Tasting Climate Change, and of course much research into the February Polar Vortex event...which interestingly happened after the panel topic was chosen.
I plan to discuss organic farming and the benefits of resilience. And then share data and trends of grape maturity for sparkling wine.
Organic viticulture, the practice of growing grapes without synthetic chemicals, can make a vineyard more resilient to climate change in several ways:
- Improved soil health: Organic viticulture relies on the use of natural fertilizers and soil amendments, which can improve soil structure and water-holding capacity. This means that the soil can retain more moisture during droughts and absorb excess water during heavy rains, reducing erosion and soil compaction.
- Improved mycorrhizal fungi networks: living soils are optimized in an organic system – pesticides, synthetic fertilizers and excessive tillage reduce populations. The expanded influence by this network to the root zone allows vines to source more nutrients to have higher tissue sugars for cold hardiness and disease resistance.
- Biodiversity: Organic vineyards typically encourage biodiversity by providing habitat for insects and other wildlife. This can help to create a more resilient ecosystem that is better able to adapt to changes in climate and weather patterns.
- Reduced carbon footprint: Organic viticulture often involves the use of more sustainable practices, such as cover cropping, reduced tillage, and the use of natural pest management strategies. These practices can help to reduce the carbon footprint of the vineyard, which can contribute to mitigating the effects of climate change.
- Resilient grape varieties: Organic viticulture may favor grape varieties that are better adapted to the local climate and soil conditions. This can result in a more diverse and resilient vineyard that is better able to withstand extreme weather events such as drought, heatwaves, or cold snaps.
Overall, organic viticulture can help to create a more sustainable and resilient vineyard ecosystem, which is better equipped to adapt to the challenges of climate change.
The 2010 growing season was the first time I felt heat that reminded me of my previous sparkling career in the Okanagan Valley of British Columbia. We had moved back to Pauline's home province in 2004 to make sparkling wine in a better climate for the style. Coincidently, that year corresponds closely to what researchers in our region identify as the start of the effects of climate change, and it marked our second vintage to earn medals at Effervescents du Monde in France.
Read more about the contrasts of making sparkling wine in the two regions.
Moderate sugars, acid retention and brown lignified (ripe) seeds are the characteristics of a world-class sparkling region, and Nova Scotia has it! As it gets warmer, though, we have been watching acidity more closely and adjusting pick dates to keep optimal freshness. See below for data from 14 years of harvesting Prestige Brut Estate from the same block showing that we have been not only maintaining freshness but also slightly trending higher acidity.
Other strategies to retain freshness in a warming climate is to prune for more crop....more grapes per vine tends to increase acidity and lower sugars at harvest. There are limits though. Champagne regulations usually have an upper limit of 10-12 tonnes per hectare, approximately 4-5 tonnes per acre, and many growers crop even higher and sell the unusable excess to distillers. But at these crop levels and higher there can be impacts on flavour and, to a lesser degree, possible nutrient deficiencies in the juice causing fermentation problems. Remember we are still striving for ripeness, and what works in Champagne might not work here in Nova Scotia. Most of the vintages listed above were cropped at 3-4 tonnes per acre, which matched our terroir of rocky well-drained soil with about 8 inches of humus-rich top soil in the block where we grow Prestige Brut Estate. And all years had brown seeds, ripeness!