From budburst to big data: The rise of phenology in a changing world

Phenology is all about timing—when trees leaf out, flowers bloom, birds migrate, animals bear young and hibernate—and it is everywhere around us. Seasonal events quietly but steadily occur in response to fluctuations in daylength, temperatures, and rainfall patterns, and these events are threaded through our daily lives, shaping our experiences and perceptions. As such, the timing of seasonal activity is being affected by rapidly changing climate conditions, with significant ecological and economic impacts.

In 2007, the Intergovernmental Panel on Climate Change called out phenology as the “simplest” process to track the impacts of a rapidly changing climate on plants, animals, and ecosystems. Later that year, the USA National Phenology Network (USA-NPN), an organization tasked with documenting and communicating about phenology, was established.

Now nearly 20 years in, the USA-NPN has become a trusted source of information. Over 20K individuals have contributed nearly 45M observations of plant and animal activity through the Nature’s Notebook platform. The USA-NPN’s data have factored into over 200 peer-reviewed publications, graduate theses, and national and international assessment reports. And USA-NPN maps regularly appear in local, regional, and national news media outlets. In this presentation, I will share the arc of phenological observing and research in the U.S., revealing how the science of phenology transitioned from a narrow field practiced only by agriculturalists and horticulturalists to a key climate change indicator.