Phenological data refers to the study of the timing of natural events in the life cycles of plants and animals. This includes observations of when flowers bloom, when trees leaf out, or when animals migrate. Such data helps scientists understand how climate change and seasonal variations affect ecosystems. Researchers collect phenological data to track changes over time and identify patterns. For example, they may analyze how the arrival of migratory birds correlates with temperature changes. This information is crucial for conservation efforts and predicting the impacts of environmental changes on biodiversity.