France, April 6 -- Climate change is causing Japanese cherry blossoms, a famous symbol of spring, to burst into peak bloom early. From Tokyo to Paris and Washington DC, nature's calendar has been disrupted by unprecedented warm weather that could ultimately prove detrimental to one of the world's most admired flowers.

A marker of seasonal change, cherry blossoms are profoundly symbolic in Japanese culture - representing both rejuvenation as well as the fleeting beauty of nature.

The centuries-old tradition of hanami - "flower viewing" - has been adopted in many countries, with crowds gathering for yearly scenic picnics beneath the fragrant pink sakura.

Forecasting the annual bloom is important business in Japan. Since 1955 the weather ...