National Geographic : 2009 Apr
ENVIRONMENT Budding Pursuit "I love those first little green leaves," says octogenarian Jean Combes of England's oaks in spring. Since age 11 she's jotted down signs of winter's end. Too bad her girlish script shamed her and she tossed her first decade of notes. Such data are vital to phenology, the study of the timing of nature's cycles. The science is gaining visibility as climate change blurs seasonal lines. Phenological data goes back to at least A.D. 705, when Kyoto royals kept cherry-blossom records. In 18th-century Europe "it began as a gentleman's pursuit, one of vicars and spinsters," says British environmental scientist Tim Sparks. Now anyone can sign up to contribute to one of numerous online databases worldwide. Combes takes daily walks to report first tree leafings to Nature's Calendar, a database out of the United Kingdom whose thousands of volunteers report on spring firsts (and fall lasts), from frog eggs to bird chirps to lawn mowings. Comparing old data with new shows the impact of rising temperatures, later frost dates, and more sunshine. As Sparks notes, "It's getting harder to answer the question: When does spring arrive?" ---Jennifer S. Holland PHOTO: ALBERT G. RICHARDS, NATIONAL GEOGRAPHIC STOCK GRAPH SOURCE: JOHN CLARKE, COURTESY NATURE'S CALENDAR, U.K. February March 1970 1980 1990 2000 EARLY BLOOMERS Daffodil bloom dates near Cambridge, England; red line shows the trend over time.