We’ve had several glorious warm and sunny spring days this week – so lucky for everyone enjoying an Easter break down here in Devon, or indeed for those of us fortunate enough to live here! I love springtime and the whole cycle of rebirth and renewal heralding the arrival of longer days and (hopefully) more sunshine – so uplifting!
Somehow, seasons used to be more clear-cut when I was a child. Summers were warmer, it always snowed at Christmas and I am sure all of that is probably poppy-cock – it’s just childhood memories that seem to change as you get older. But what really makes our seasons and the weather that they bring? I thought I’d investigate…
What causes the seasons?
The seasons are a result of the tilt of Earth’s axis in relation to the Sun as we orbit around it. This tilt (all 23.5º of it!) means that throughout our orbit around the sun (which is our calendar year) certain areas of the earth are tilted towards the Sun, while other areas are tilted away from it. This creates a difference in the amount of sunlight that reaches different parts of the Earth and that’s how we get the seasons.
When does spring officially start?
Well, that depends on whether you are referring to the astronomical or meteorological spring.
The date on our calendars that marks the start of spring refers to the astronomical season which is a result of the Earth’s axis and orbit around the sun. However, organisations like the Met Office use meteorological seasons based on the annual temperature cycle as well as coinciding with the calendar to determine a clear transition between the seasons.
Since the astronomical seasons vary in length, the start date of a new season can fall on different days each year. This makes it difficult to compare seasons between different years and resulted in the introduction of the meteorological calendar. This splits the calendar into four seasons of approximately the same length. The astronomical seasons run approximately three weeks later than those of the meteorological calendar. So now you know!
Which is your favourite season?
Do tell me your favourite. I think I could make a case for each season in turn and I am very grateful to live in a country where there are actual seasons rather than constant sunshine… would one of you remind me I said that in the depths of next winter please!