Quizzes & Puzzles22 mins ago
Summer Time
Once again the longest day, 21st June, is not far off. Diaries and calendars tell us the 21st June is the Summer Solstice and summer begins. It seems odd to me that summer should begin at a time of year when days are going to start getting shorter. Why is the longest day not mid-summer? What do others think about it?
Answers
This answer is a direct copy-&-paste from one I posted one a similar thread (which was actually about the first day of autumn) last yearbut it still seems to be relevant: There's no (single) 'official' day for the start of any season. Different people use different definitions. For example (since the sun reaches its highest point in the sky around that date),...
20:56 Sun 17th May 2015
This answer is a direct copy-&-paste from one I posted one a similar thread (which was actually about the first day of autumn) last yearbut it still seems to be relevant:
There's no (single) 'official' day for the start of any season. Different people use different definitions.
For example (since the sun reaches its highest point in the sky around that date), midsummer's day (aka the summer solstice) is on June 21st, with the winter solstice (with the sun at its lowest point in the sky) being on December 21st. Assuming all of the seasons to be of equal length, each season must be about 91 days long, so the start and finish of summer must therefore be roughly 45 days either side of June 21st, making the last day of summer around August 12th.
However while that method of deciding when each season starts and ends might find favour with astronomers, it doesn't fit very well with most people's perceptions of when the seasons actually occur.
Meteorologists have a far simpler way of looking at it: June, July and August are the warmest months in the UK, so those three months fall into 'summer'. That means that September, October and November form 'autumn'. December, January and February make up 'winter', while March, April and May are grouped together as 'spring'.
There's no (single) 'official' day for the start of any season. Different people use different definitions.
For example (since the sun reaches its highest point in the sky around that date), midsummer's day (aka the summer solstice) is on June 21st, with the winter solstice (with the sun at its lowest point in the sky) being on December 21st. Assuming all of the seasons to be of equal length, each season must be about 91 days long, so the start and finish of summer must therefore be roughly 45 days either side of June 21st, making the last day of summer around August 12th.
However while that method of deciding when each season starts and ends might find favour with astronomers, it doesn't fit very well with most people's perceptions of when the seasons actually occur.
Meteorologists have a far simpler way of looking at it: June, July and August are the warmest months in the UK, so those three months fall into 'summer'. That means that September, October and November form 'autumn'. December, January and February make up 'winter', while March, April and May are grouped together as 'spring'.
-- answer removed --
As far as I am concerned the solstice & equinox define seasons.
(Meteorologists, poor souls, are clearly unable to cope.)
Solar and lunar calendars are not necessarily instinctive, they never seem to sync together properly :-)
Surely the shortest day defines mid-summer ?
I suspect folk also get a feeling all is not as it should be, because the heat cycle lags the light cycle. Due to the need to heat up the place, we are getting longer days whilst our part of the Earth is experiencing summer, but the land is still heating up and will do so for a while when the days are already starting to get shorter again. It's like living on a great big heat sink. So the seasons seem to be arriving and leaving after the lighting has already changed.
(Meteorologists, poor souls, are clearly unable to cope.)
Solar and lunar calendars are not necessarily instinctive, they never seem to sync together properly :-)
Surely the shortest day defines mid-summer ?
I suspect folk also get a feeling all is not as it should be, because the heat cycle lags the light cycle. Due to the need to heat up the place, we are getting longer days whilst our part of the Earth is experiencing summer, but the land is still heating up and will do so for a while when the days are already starting to get shorter again. It's like living on a great big heat sink. So the seasons seem to be arriving and leaving after the lighting has already changed.