Donate SIGN UP

When is spring - how can you tell And is it getting earlier

00:00 Mon 18th Mar 2002 |

asks dekhay:
A.
Yes, spring is getting earlier. According to the records, this year had one of the warmest first couple of months since record began 300 years ago.

Q. Hasn't it been rather parky
A.
Well, it's certainly been windy, and rainy. But there hasn't been much frost or ice about, has there

Well, now that you mention it...
The average UK temperature from mid-January to mid-February this year was 8.2C - that's about 4.4C above the long-term average.


There were signs this year that spring began earlier than usual too: daffodils, primroses and blooming, frog spawn was seen as early as December last year (tadpoles normally emerge in the second half of March); buds on horse chestnut trees in February instead of late March; the first swallows are now wintering further north and have started arriving here in late March rather than April.

Q. So when does spring begin officially
A.
March 21, but this date doesn't really have much meaning and spring to starting to stretch. According to the Met Office, British winters are getting short and mild, while spring and autumn are getting longer.

Q. So this isn't just a one-off
A.
No. January and February temperatures are on the increase, and winter frosts are decreasing.

Q. What will warmer winters mean
A.
They will affect animals and birds mainly. Scientists fear that feeding and breeding cycles, which depend on food supplies being available at exactly the right time, are being interrupted. For example, many mammals are coming out of hibernation earlier but there's nothing for them to eat; and the great tit depends on moth larvae being born at the same time as its young so the hatchlings can feed on them; and young cuckoos eat hairy caterpillars - but if leaves come out too early and are too tough for the caterpillars to eat, the cuckoos and the caterpillars will decline.

There are thousands of people already looking out for indicators that the seasons are changing, such as seven-spot ladybirds, bluebells, bumblebees, queen wasps, swifts and swallows. This study of seasonal change is called phenology. A study by the UK Phenology Network, called Nature's Calendar, is using volunteers to look out for many natural indicators of season change - visit the website to find out more.


Do you have a question for How it Works Post it here

By Sheena Miller

Do you have a question about How it Works?