Did you know spring green-up is a phenophase transition observable from space? Scientists are using satellite images to assess changes in timing of green-up. Unfortunately, we’ve only been collecting these images since 1972 so we don’t have a long historical record to which we can compare contemporary records. Nevertheless, satellite images are providing g a new tool for those who study phenology that will become even more valuable in years and decades to come.
(Editor's note: Kay Havens is on travel and asked me to submit this for her.)