Italy's best vines were moving from the south to the north because of climate change, said Cotarella, one of the most respected voices in Italian wine, at a tasting event in London this week. His comments add to growing concerns over the last couple of years about how rising global temperatures could affect some of the world's best vineyards. Cotarella, now a consultant, said stronger rays from the sun, associated with global warming, presented particular problems for wineries on the coast. "A few years ago we considered the sea coast one of the best places, but this is not true today. The problem is the sunlight, the UV rays." He likened the effects of strong sunlight on grapes to sunburn. "If I go to the beach, if I don't protect my skin with cream I will burn. It is the same for the skin of the grapes." New technology, perhaps mimicking sun cream, could one day be developed to help winemakers protect their grapes, Cotarella told guests at a tasting for 25 Italian wineries he consults with. Global temperatures are expected to rise around 2C up to 2050. It is a prediction causing concern across the global wine industry, which faces disruption in traditional production areas. Huge swathes of California's Napa valley may cease to exist if temperatures continue rising at their current rate, according to US academic Gregory Jones. Napa is currently perfectly placed to produce top wines from its most popular grape varieties, but more temperature rises will be a test of how the region is able to adapt, Jones said at a conference last year. There was visible discomfort from American guests as Jones unveiled a map of Napa 50 years on, its vineyards decimated. Some of the effects of global warming are perhaps already showing, as Australia's wineries experience their worst drought on record. A recent industry conference in Dijon, France, suggested water shortages could be just as harmful as rising temperatures. Other wine growing regions may benefit from climate change, however. In Italy, Cotarella said a slight rise in temperatures meant the Sangiovese grape "can finally get the best ripeness". He added: "climate change presents major problems for some areas and varietals and opportunities for others".