Fenologi

Fenologi, or phenology, is the study of the timing of recurring biological events in plants and animals and how these timings relate to seasonal and interannual climate variation. The field focuses on the seasonal cues that regulate life cycles, such as leaf unfolding, flowering, fruiting, insect emergence, and the migration or breeding of birds. Phenological observations reveal the timing of events (phenophases) and how these timings change from year to year and across regions.

Researchers analyze long-term observations to detect trends and infer the climate drivers of timing, including temperature, day length (photoperiod), and chilling requirements. Methods combine field observations, herbarium and museum records, remote sensing, and process-based or statistical models that relate event timing to climate variables, often using metrics like growing degree days.

Applications of phenology include serving as an indicator of climate change, informing agriculture and forestry about expected crop or pest phenology, aiding biodiversity monitoring, and improving ecological models that depend on the timing of interactions among species.

Data on phenology are collected through national and international networks and citizen-science programs. Notable examples include the USA National Phenology Network and Nature's Calendar in the United Kingdom, which gather and share long-term records of plant and animal life-cycle events to support research and public awareness. Challenges include ensuring data consistency across regions, separating climate signals from other drivers, and accounting for local variability. As a climate-sensitive signal, fenologi remains a key tool for understanding ecological responses to global change.