Latitude and the Wine Belt

Latitude is the angular distance north or south of the equator, measured in degrees and minutes. Most of the world's vineyards are planted in the temperate latitude zones of 30 to 50 degrees north and 30 to 50 degrees south, and within those zones the actual climate has a huge influence on the type of wine produced. WSET describes the same band as where optimal conditions are generally found, on either side of the equator. Very few vineyards sit closer to the equator than 30 degrees, because it is generally too hot there. Gregory Jones, writing for GuildSomm, notes vineyards as far north as Scandinavia, where a warming climate helps, and near the equator in Brazil, where two crops per year are produced.

• Most vineyards: 30 to 50 degrees north and 30 to 50 degrees south of the equator
• Closer to the equator than 30 degrees: very few vineyards, because it is generally too hot
• Outliers exist at both ends, from Scandinavia to Brazil

Latitude works through light and warmth. Incoming solar radiation, called insolation, provides the energy for grape growth and maturation: during ripening it mainly controls how much sugar the grapes build, and therefore the wine's potential alcohol. How much sunlight a site receives depends partly on the Earth's relationship with the sun, including the seasonal angle at which the sun's rays arrive and the length of the day. Warmth matters as much as light. Grapevines are grown where growing-season temperatures average 55 to 70°F (13 to 21°C), limits found mostly in the mid-latitudes. Vine growth starts in spring when the mean daily temperature reaches approximately 50°F (10°C), and the growing season for wine grapes averages approximately 170 to 190 days. The closer a vineyard is to the equator, the warmer it becomes, and cooling influences such as sea breezes or mountain air may be needed to keep it from getting too hot. Further from the equator the reverse is true, and growers look for anything that maximises warmth and sunlight to ripen the grapes.

• Sunlight during ripening mainly sets sugar levels, and so potential alcohol
• Sun angle and day length are Earth/Sun controls on how much sunlight a site receives
• Growing-season average of 55 to 70°F (13 to 21°C) marks where grapevines are grown
• Growing season for wine grapes averages approximately 170 to 190 days

Two vineyards on the same line of latitude can live in very different climates. Latitude is one clue to how a wine will taste; altitude and the sea, including warm and cold ocean currents, are others. In warm places altitude brings relief: WSET notes that for every 100 metres climbed above sea level, the temperature drops approximately 0.6°C. Gregory Jones calls latitude comparisons often misused or misunderstood, and only partially correct unless you also know whether a region sits on an east or west coast and how far inland it is. His example is Bordeaux and Napa Valley. Bordeaux is substantially more humid, with much greater rainfall during the growing season, than the commonly compared Napa Valley, and that difference mostly comes down to offshore ocean temperatures and the orientation of the coastlines. WineWiki's articles on continental climate, maritime moderation and altitude go deeper on each of these modifiers.

• Altitude: temperature drops approximately 0.6°C per 100 metres of elevation
• Ocean currents and offshore sea temperatures reshape climate at a given latitude
• Coast orientation and distance inland matter as much as the latitude number

Champagne sits on the northern edge. Champagne.fr places Reims at a latitude of 49°5 north and Épernay at 49°, and notes that in the Northern Hemisphere it is generally considered difficult to obtain quality grapes at the 50th parallel. Its vineyards sit right on the borderline, which, it says, explains why the weather is sometimes very challenging. The Barossa Valley in South Australia sits well inside the southern band: Wine Australia gives the region's latitude as 34.71 degrees south, measured at the centre point (centroid) of the region. Central Otago marks the far south. New Zealand's wine regions span the latitudes of 36 to 45 degrees, and Central Otago is the country's southernmost. New Zealand Wine calls it the world's most southerly wine region, with a semi-continental climate that is dry with extreme variation between summer and winter temperatures. For scale, New Zealand Wine notes that the northern-hemisphere equivalent of its span would run from Bordeaux, between the latitudes of 44 and 46 degrees, down to southern Spain.

• Champagne: Reims at 49°5 north, Épernay at 49°, right on the borderline
• Barossa Valley: 34.71 degrees south (region centroid, per Wine Australia)
• Central Otago: southernmost of New Zealand's regions, which span 36 to 45 degrees
• Bordeaux: between the latitudes of 44 and 46 degrees

Near the cool, poleward edge, grapes ripen slowly. In a cool country like Germany, grapes not picked until the end of October still retain high levels of acidity, while sugar builds slowly and the wine ends up relatively light in alcohol. A hot climate usually does the opposite, giving more alcohol and soft acidity. Less ripe grapes typically make wines with less alcohol, more acidity and fresh fruit aromas; very ripe grapes give more alcohol and very ripe or even cooked fruit flavours. Going past the belt shows the trade-off clearly. UK wine regions typically sit between 51 and 53 degrees north, beyond the 30 to 50 degree band typically considered suitable for high-quality wine, yet WSET points to long daylight hours over the growing season that allow slow ripening and time for complex aromas and flavours to develop. Toward the equator the problem flips: extreme heat above 95°F (35°C) can shut down the vines by inhibiting photosynthesis.

• Cool edge: slow ripening, high acidity, lighter alcohol
• Warm side: more alcohol, softer acidity, riper fruit flavours
• UK at 51 to 53 degrees north relies on long daylight hours for slow ripening
• Heat above 95°F (35°C) can shut down photosynthesis

Primary and reference sources used for this article: https://www.wsetglobal.com/knowledge-centre/blog/2021/august/24/how-does-geography-affect-a-wine-s-style https://www.guildsomm.com/public_content/features/articles/b/gregory_jones/posts/climate-grapes-and-wine https://www.decanter.com/learn/wset/factors-that-influence-wine-conditions-and-growing-environment-wset-level-2-282900/ https://www.decanter.com/learn/winemaking-the-facts-2-54064/4/ https://www.champagne.fr/en/about-champagne/the-champagne-terroir/champagne-and-its-climate https://www.wsetglobal.com/knowledge-centre/blog/2022/june/21/an-introduction-to-english-wine https://www.nzwine.com/en/media/story/intro-to-nz-wine/ https://www.nzwine.com/media/19385/central-otago.pdf https://www.wineaustralia.com/getmedia/cd4203e4-0326-48c7-9516-2287a26887b0/MI_Barossa-Valley-Region-Snapshot-2023-24.pdf https://www.nzwine.com/en/regions/centralotago/ https://www.jancisrobinson.com/ocw/detail/latitude Last verified 2026-09-24