In astronomy, of course, where multi-decade records sparked the Age of Wonder, long-term datasets are now routine. Ditto geology, the discipline which made it possible to conceive deep time. But other fields, especially in the life sciences, are just catching up.
In the 20th century, biologists, ecologists and epidemiologists launched many long-term studies, designed with an eye beyond their own time. More recently, researchers have mined records — from captains' logs to Google Books — that in retrospect contain useful data. The approaches embody some of science's great virtues: foresight, patience and cleverness.
On the following pages, Wired Science presents some of its favorite long-term datasets.
In Japan, cherry blossom festivals are an ancient and wildly popular tradition, featuring days-long celebrations carefully timed to coincide with peak flowering. The festivals are so prominent in Japanese culture that their collective descriptions in diaries, literature and administrative records have been turned into a six-century-long record of blossoming dates and locations across the islands.
Because the trees blossom at certain temperatures, scientists can infer historical weather information, and ultimately climate trends, from these dates. Few other historical climate records contain such fine-grained detail.
Images: Above) Kazuhiko Teramoto/Flickr Below) Top row, the known dates of full cherry flowering from the 11th century to present. April 1 is the year's 91st day, and May 1 is the 122nd. Bottom row, estimated historical March temperatures as calculated from flowering dates. (Yasuyuki Aono & Yuko Omoto/Journal of Agricultural Meteorology)