Climate change in a glass: How a warming world is altering wine

First published in The Irish Times, Saturday 18th May.

According to the viticulturist Dr Richard Smart, the world’s wine industry “is the canary in the coal mine, because it’s the early-warning system”. A map of the world’s wine regions shows that almost all vineyards lie in two narrow ribbons, between 30 and 50 degrees north and south of the equator. This is changing gradually, partly because of increasingly sophisticated methods of viticulture but also because, all around the world, grapes are ripening earlier.

Even a degree or two’s change in annual temperatures can make a huge difference to the quality and style of a wine – which is why every vintage is unique. There will be winners and losers: cool regions such as the Loire and southwest France, Hawke’s Bay, in New Zealand, and Tasmania, in Australia, once had difficulty ripening red grapes. Nowadays they don’t. Very high quality sparkling wine is now being produced in the UK.

At the other extreme, warmer areas such the southern Rhône in France, central Spain, parts of California and the Barossa Valley in Australia may become too hot to sustain viticulture. Irrigation, once commonplace in hot regions, may become expensive or illegal. Increased ripeness means higher sugar levels, leading to more alcohol. In classic regions, such as Bordeaux and the Napa Valley, alcohol levels have increased over the past 20 years from 12.5 per cent to 14.5 per cent and more – a lot of Napa Valley wines now comes in at over 15 per cent. Yet many consumers are looking for lighter wines with lower alcohol.

A producer can chose to pick early to keep sugar levels low, although the danger is that the phenolic compounds, tannins and anthocyanins essential to high-quality wine may not have ripened yet.

Forward-looking producers such as Miguel Torres in Catalonia long ago began planting vines at much higher altitudes and investigating possible alternative grape varieties. (Torres is also investigating carbon capture and storage.) Others without that option are looking at planting vines on their cooler, north-facing slopes or adjusting their leaf canopies to protect grapes from sunburn.

The other option is to plant varieties that can thrive in warmer, drier climates. Here the Mediterranean countries have plenty of ancient indigenous varieties to offer. White grapes, such as Vermentino and Fiano from Italy and Arinto from Portugal, retain their acidity even in hot climates. For red wines, expect to see more Touriga Nacional, Castelâo and Trincadera from Portugal, as well as Nero d’Avola, Aglianico and Grenache instead of Cabernet Sauvignon and Pinot Noir.

But most European wine regions are restricted to growing a limited number of grape varieties, and marketing Sauvignon Blanc or Malbec is a lot easier than marketing Aglianico.

Of course, this doesn’t address the other effects of climate change: extremes in weather, such as storms, floods or drought, as well as frost and hail are all predicted to increase.

Castellini Vermentino 2017, IGT Toscana
12.5%, €10 (down from €16.99) from Thursday, May 23rd

Floral, herbal nose with plump pear and ripe peach fruits, with good refreshing acidity. On its own, or with Italian fish dishes – spaghetti with clams, mussels or prawns.
From SuperValu, supervalu.ie

Prova Regia Arinto 2017, Bucelas, Portugal
12.5%, €13.95

Move over Sauvignon. Stimulating, appetisingly fresh and crisp with bright luscious fruits and a racy mouth-watering acidity, finishing dry. As an aperitif, or with grilled white fish.
From O’Briens, obrienswine.ie; Fresh, freshthegoodfoodmarket.ie; La Touche, Greystones, Co Wicklow,latouchewines4u.ie; Matson’s, Grange and Bandon, Co Cork; MacGuinness Wines, Dundalk, Co Louth, dundalkwines.com; the Corkscrew, Dublin 2, thecorkscrew.ie; Donnybrook Fair, Dublin 4, donnybrookfair.ie; Deveney’s, Dublin 16; D-Six Wines, Dublin 6; peggykellys.ie; Red Island Wine, Skerries, Co Dublin; Redmonds, Dublin 6, redmonds.ie; Morton’s, Dublin 6,mortons.ie; Listons, Dublin 2, listonsfoodstore.ie; Jus de Vine, Portmarnock, Co Dublin,jusdevine.ie; Baggot Street Wines, Dublin 4, baggotstreetwines.com; McCabes, Dublin 18; the Coach House, Dublin 16, thecoachhouseofflicence.ie; Lilac Wines, Dublin 3, lilacwines.ie; Sweeneys Wines, Dublin 11, sweeneyswines.ie.

Fossil 2015, Vale de Capucha, Lisbon (organic)
13%, €20

Made with 60 per cent Touriga Nacional, this wonderful, moreish wine with violet aromas, lively concentrated dark fruits – blackcurrants, blackberries and wild fruits, with a strong, refreshing mineral streak, is unputdownable. Try it with pork dishes – grilled chops or a herby roast.
From Urbanity, Dublin 7, urbanity.ie; Green Man Wines, Dublin 6, greenmanwines.ie; Lilac Wines, Dublin 3, lilacwines.ie; Grape & Grain, Stillorgan, Co Dublin,leopardstowninn.ie; Baker’s Corner, Kill of the Grange, Co Dublin; 1601 Off-licence, Kinsale, Co Cork; Baggot Street Wines, Dublin 4, baggotstreetwines.com; Drinkstore, Dublin 7,drinkstore.ie; Martin’s Off-Licence, Dublin 3, martinsofflicence.ie.

Mont Horrocks Nero d’Avola 2017, Clare Valley, Australia (organic)
13.7%, €39.99

Australian Nero d’Avola: a sign of the future? This one is excellent: medium to full bodied, with perky bright red cherry fruits, touches of spice and smooth, gentle tannins on the finish. Drink cool with herby grilled chicken.
From wineonline.ie; Blackrock Cellar, Co Dublin, blackrockcellar.com.