The world’s most successful wine regions lie within latitudes 30-50° North and South. Within these diverse temperate zones, some grape varieties such as Riesling, Pinot Noir, and Sauvignon Blanc do best in cooler, more marginal climates. Others, such as Grenache, Nero d’Avola, and Touriga Nacional call for much hotter conditions. Cabernet Sauvignon insists on a moderate but sunny climate, whereas Chardonnay is adaptable, yielding lean and mineral wines in cool Chablis but blousy and buttery wines in hot parts of South Australia. Generally speaking, white varieties need less heat than black varieties, and so predominate in the coolest, most marginal regions such as southern England, Champagne, and the Mosel. Wines from such marginal regions may be softened or made more palatable by double fermentation, arrested fermentation (to retain residual sugar), the addition of sugar, or ageing on the lees.