Australia's Science Forum

This is a question that Robb may be able to answer....

In Australia (due to ease or laziness) we say that seasons start on the first of the month. I understand that this is to make collecting data and statistics easier?

Let's work with Summer..... Summer 'starts' Dec-1. The solstice is Dec-21. Officially this is the start of summer (that's what my Northern Hemisphere wife says - and I've never been able to convince her she is wrong about anything).

If the solstice is the start of summer, then why was 'midsummer' around this date. If seasons are 13 weeks long, summer presumably 'starts' 6 weeks prior to mid summer, hence should technically be 'starting' around the Nov-9.

I once heard also, that the 'seasons were moving' - is this correct?

Or am I totally confused?????

now i'm confused....this is heavy for week 9 of 10

In England we were told, it is the 21st of march, for Spring, 21st June for Summer, Midsummer is about 23rd July. 21st Sep for Autumn 21st Dec for Winter. When I came out here I was told it was the 1st of the said months. So I will be very interested tohear robb's story.

Ditto for me in the UK, solstices and equinoxes. I think that is known as the astronomical season. I always thought of June as summer though even though it didn't start until 21st (if at all!). And winter definitely starts earlier than 21st December there. Even after 5 years here I still find the seasons confusing. I now have a winter birthday instead of a summer one which is a bit of a bummer, and can't get to grips with Easter in autumn!

If you assumed that the summer solstice was the beginning of summer, then your summer would include a period when the sun was lower in the sky at the end of summer then it was at the end of the previous spring. So you would think that during the summer period the angle of the sun should be the same 6.5 weeks prior to solstice as it is 6.5 weeks after?
However, ( Apparently) the summer period is determined by average temperatures as opposed to the angle of the sun, due to the fact the earth takes a while to heat up (and cool) the start and finish time is slightly delayed.?

Narelle01 wrote:now i'm confused....this is heavy for week 9 of 10

put the air conditioner on, turn the heater on, anything between beautiful.

still I'd be interested to know the answer.

CoolestGuyinSchool wrote:Let's work with Summer..... Summer 'starts' Dec-1. The solstice is Dec-21. Officially this is the start of summer (that's what my Northern Hemisphere wife says - and I've never been able to convince her she is wrong about anything).

If the solstice is the start of summer, then why was 'midsummer' around this date. If seasons are 13 weeks long, summer presumably 'starts' 6 weeks prior to mid summer, hence should technically be 'starting' around the Nov-9.

I once heard also, that the 'seasons were moving' - is this correct?

Astronomically, the solistice mark the turnabout in the lengthening/shortening of night. Summer solistice is the shortest night of the year, winter solistice is the longest. This would make them the middle of the seasons; mid-summer and mid-winter respectively. Likewise the equinoxes mark when day and night are of equal length, which should make them mid-spring and mid-autumn.

However, meteorologically, the temperature changes tends to lag a few weeks behind the astronomical changes; by an amount depending on locale climate and geography. Calendars mark the seasons by weather rather than daylength. It's not exactly so, but in Australia the firsts of the months are a close enough approximation to the cut off.

I have found this thread very interesting as it is not something I have ever considered! I just assumed the rest of the world also started their seasons on the first of the month as well!! Never too old to learn something

Robb, where are you, when we need you!!!
I too, come from northen hemisphere and our winter starts on 21st Dec. The fact that summer here starts on 1st of dec is least of my problem, it is the long cold nights over xmas break I dont miss. Must admit, my life will not change if the seasons start on the 1st or 21st of that month.
Lada

Thanks to this thread I have had the song in my brain all day

From the discussion it seems it is "seasons out of time"

I wondered if those of us who are not of a certain age were thinking "what is he on about with that title?"

I read somewhere that in the past (in the UK at least) May Day was the first day of summer and so 21st June, summer solstice, was midsummer's day. Not sure why this has changed over time though.

I wish I, too, could get the song out of my head.......

Funny... last two September 1sts I have started sneezing right on the start of spring!!!