Nature’s Calendar: Phenology and Participatory Climate Science
- Luis Diego Molina
- Apr 29
- 4 min read
Updated: Apr 30
This article is based on insights shared during our April 21 Alumni Webinar Series presentation, Plant Phenology and the Science of Seasonal Change, featuring Joe Loviska, EPI’s Yellowstone Program Manager.
For the past three years, Joe has closely observed the flowering process of a serviceberry tree (Amelanchier alnifolia) outside his office. As he explained during the webinar, something as simple as watching leaves and flowers emerge in early spring can be a powerful way to do climate science.
How is that possible? Through phenology, the study of the timing of life cycle events in plants and animals in relation to environmental factors such as climate, weather, and photoperiod. In states with four distinct seasons, like Montana, phenology can be understood as the study of seasonal change, which governs many of the cycles of living organisms.
Photos taken by Joe of the moment when the serviceberry tree sprouted its first leaves in the last three years
Systematically recording when the first plants bloom, for example, helps us understand when spring begins each year. Comparing those observations with historical records can reveal whether the timing of the seasons is shifting.
In Missoula, Montana, for instance, spring arrived 20 days earlier than average this year. But this pattern is not unfolding uniformly across the country. While spring came early in the Rocky Mountains, in the Southeast, paradoxically, spring has been arriving later, with longer winters and extreme weather events such as ice storms.
“Phenology is climate science. It shows us climate change in a very real way,” explains Joe.
These shifts in plant behavior are driven not only by temperature differences, but also by factors such as moisture, photoperiod (the duration of daylight), and the number of winter chilling days, creating a web of complex relationships.
How does an earlier spring affect wildlife? In Joe’s words:
“Imagine that I’m a migratory bird and I need food as I go north and if the food that I’m used to having isn’t there this year then that’s going to be a problem for me. Or I show up to a region where I expect there to be leaves on the trees to hide me for nesting and there are no leaves on the trees that might be a problem.”
Phenology Applied to a Large-Scale Case Study
A concrete example of how phenology reveals climate change comes from a recent study published in the Journal of Applied Meteorology and Climatology. Temperatures are rising particularly fast in the northeastern United States as a result of human-caused warming.
A group of researchers compiled climate and plant data from the New Jersey region dating back to the mid-1960s. They evaluated changes in daytime and nighttime air temperatures, sea surface temperatures, lake ice persistence, and winter snowfall. They also used observational data to examine whether lilac phenology has changed over time.
The researchers found evidence of change across all variables studied. Since 1967, the New Jersey region has experienced an increase in the number of hot summer days and nights, along with a decrease in winter severity and lake ice cover. These climatic shifts have also led to earlier spring plant activity.
All of this information is valuable for shaping public policies focused on climate change mitigation and adaptation.
Phenology as an Educational Tool
For Joe, one of the reasons he is so passionate about phenology is its power as a tool for environmental education. It began while he was pursuing his master’s degree at Western Washington University, where he coordinated a project in North Cascades National Park in which fifth-grade students regularly observed marked plants.
Through that experience, he realized students could contribute their observations to national databases that inform climate scientists, while also building a direct connection with their local environment.
Joe sees one especially valuable tool for educators in Nature’s Notebook, developed by the National Phenology Network (NPN), a virtual platform that allows users to establish observation sites (for example, in a schoolyard), track individual plants, and make regular observations with students. The website includes an entire section devoted to bringing Nature’s Notebook into the classroom, including complete lesson plans: https://www.usanpn.org/nn/education
At EPI, we deeply believe in the power of participatory science, and all our courses put it into practice. While not always through phenology, our programs engage students in studying the ecology of diverse species across conservation sites in five countries. Data collected by our students have contributed to publications about changes in herbivore feeding behavior in Yellowstone and they form the foundation of our long-term sea turtle research at Pacuare Reserve on Costa Rica’s Caribbean coast, among many other examples.
“Participatory science is a very powerful tool to bring learners into direct connection with the natural world, using skills of observation that they might be growing in the moment, and then also participating in the scientific process,” says Joe.
If you’d like to watch the full webinar, you can find the recording here:
