Spring is here – we all love to notice signs of renewal of the season – but when exactly is the start of Spring?
There are three different measures we can use:
Meteorological – fixed every year to ensure statistics are consistent throughout time. Spring in the northern hemisphere starts on 1 March and autumn on 1 September. Dates have been decided using temperature data.
Astronomical – follows the equinox and can vary slightly each year. Spring falls between 19-23 March and autumn 22-24 September. In 2025 astronomical Spring begins on the 20th March
Phenological – follows biological events and their response to weather and climate. This is a fascinating study which shows how nature reacts to changes in climate. Nature’s Calendar uses public sightings of plants, animals and fungi to track the effects of weather and climate on nature. This is a Citizen Science project from the Woodland Trust.
To see how this works see the BBC article here . Find out more about the Nature’s Calendar project here