Winemakers seek to improve grapes

Increasing heat leads to more sugar and higher levels of alcohol

Amid the bustle of a busy harvest in France's famed Beaujolais wine-making region, a quiet effort is underway to counter one of the industry's biggest potential threats: climate change.

As seasonal pickers set up their tents and tractors cart away bulging crates of grapes, scientists scrutinize a plot of land set aside to cultivate experimental varieties of the fruit.