NORTHERN RHÔNE: The northern Rhône is characterised by a continental climate with harsh winters but warm summers. Its climate is influenced by the mistral wind, which brings colder air from the Massif Central. Northern Rhône is therefore cooler than southern Rhône, which means that the mix of planted grape varieties and wine styles are slightly different.
Syrah is the only red grape variety permitted in red AOC wines from this sub-region. The grape, which is believed to have originated in or close to the Rhône region, is also widely known as Shiraz, its name in Australia and much of the English-speaking world, and has recently become very popular with consumers around the world. For wines bearing the Cornas AOC designation, Syrah must be used exclusively, whereas other reds from the northern Rhône sub-region may be blended with white wine grapes, either Viognier or Marsanne and Roussanne, depending on the appellation. However, while this is allowed by the AOC rules, blending with white grapes is widely practiced only for Côte-Rôtie.
SOUTHERN RHÔNE: The southern Rhône sub-region has a more Mediterranean climate with milder winters and hot summers. Drought can be a problem in the area, but limited irrigation is permitted. The differing terroirs, together with the rugged landscape which partly protects the valleys from the Mistral, produce microclimates which give rise to a wide diversity of wines. A feature of the cultivation of the region is the use of large pebbles around the bases of the vines to absorb the heat of the sun during the day to keep the vines warm at night when, due to the cloudless skies, there is often a significant drop in temperature.
The southern Rhône's most famous red wine is Châteauneuf-du-Pape, a blend containing up to 19 varieties of wine grapes (ten red and nine white) as permitted by the Châteauneuf-du-Pape AOC rules. Other nearby AOC regions including Côtes du Vivarais AOC, Grignan-Les Adhemar AOC, Lirac AOC, Tavel AOC, Vacqueyras AOC, and Ventoux AOC may contain even more varieties in the blend. Gigondas AOC, on the other hand, is predominantly made from Grenache noir has a more restricted set of permitted grapes. Depending on the specific AOC rules, grapes blended into southern Rhône reds may include Grenache, Syrah, Mourvèdre, Carignan and Cinsault. Similar wine blends globally are known as GSM, after the first three varietals. The reds from the left bank are full bodied, rich in tannins while young, and are characterized by their aromas of prune, undergrowth, chocolate and ripe black fruit. The right bank reds are slightly lighter and fruitier.