http://www.sciencemag.org/news/2018/07/top-stories-cycling-and-climate-change-hidden-pharma-payments-and-cursing-surgeons

36 years of bike race footage reveals how Belgium’s climate is changing

Green-thumbed grandmothers the world over have noticed a disturbing trend: Spring seems to be arriving earlier every year. But without hard data, it’s difficult to back up those claims. Now, scientists have found a new source of data—old television footage of outdoor sporting events, which reveals how early trees and other plants are “leafing out” each year.