the study of periodic events


phenology = Phänologie; eine Wissenschaft, die sich mit den Beziehungen zwischen Klima und periodischen biologischen Phänomenen (wie Vogelzug oder Pflanzenblüte) befasst



“In New York, one of several US cities to experience its warmest January on record, spring conditions have arrived 32 days before the long-term normal, which is its earliest onset of biological spring in 40 years of charting seasonal trends by the National PHENOLOGY Network.”

Oliver Milman — The Guardian (24th February 2024)

“Take a look at our handy PHENOLOGY calendar to see what else you could be looking out for… Hazel first flowering (when the catkins open up and begin to release their yellow pollen) can usually be spotted in January.”

Lorienne Whittle — Woodland Trust (10th January 2022)

Did you


- a branch of science dealing with the relations between climate and periodic biological phenomena (such as bird migration or plant flowering)

- periodic biological phenomena that are correlated with climatic conditions



The term "phenology" is derived from the Greek phaino- which means "to appear" or "to bring to light" and the suffix -logy which denotes "the study of”. The word made its debut in European scientific literature in the 19th century, specifically in 1884.

Interestingly, the term "phenology" has also spawned derivatives: "phenophase" referring to a specific recurring stage in an organism's life cycle, like leaf bud burst or bird migration; "phenogram" which visually depicts the timing of various phenophases for different species within an ecosystem; and "phenometer", an instrument used to measure environmental factors influencing cyclic events.


Phenology, often described as nature's calendar, is a fascinating field that studies the timing of recurring natural events in plants and animals. From the first bloom of a flower to the migration of birds.

By tracking the timing of these events, scientists can unravel the impacts of climate change, predict pest outbreaks, and even inform urban planning decisions. Farmers rely on phenology to determine the best times for planting and harvesting, while conservationists use it to protect biodiversity and ecosystems.

Next time you witness a robin building its nest or a tree bursting into bloom, remember that you're witnessing phenology in action, right there, smack dab in front of you.


- for recurring again:

annual, biyearly, biennial, bisannual, cadence, come again, constant return, cyclical, cyclicality, decennial, echo, encore, five-yearly, generational, happen again, iteration, loop, oscillation, periodicity, perpetuation cycle, perennial, predictable reappearance, predetermined return, pulsation, recurrence, reemergence, reiteration, renewal, repetition, return, rhythm, round, seasonal, septennial, serial, series, triennial, yearly

SMUGGLE OWAD into an English conversation, say something like:

“Climate scientists rely on PHENOLOGY data to analyze long-term trends in natural events.”

THANKS to Florian for suggesting today’s OWAD

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