Season Indicators: Know When Seasons Start & End

[navneet1990]

what indicates the birth and death of seasons?
how can you say when a season has begun or is going to end??

 

[neutrino]

http://aa.usno.navy.mil/faq/docs/seasons_orbit.html

 

[Hurkyl]

The seasons start when they're defined to start. The usual definition (at least in the U.S.) is that the equinoxes and solstices mark the boundaries between seasons.

 

[navneet1990]

but how can you just say that
can you give examples or anything to give ground to that
do the behavior of plants also take such sharp turns or are tey not connected with seasons

 

[Hurkyl]

You asked when the seasons begin and end. I told you. I don't really understand your problem.

The U.S. usually uses astronomical reckoning to decide when the seasons start. Other places may use meteorological reckoning, or something entirely different.

But the point is, the word "season" has a meaning. In the U.S., that meaning is in terms of solstices and equinoxes.

 

[cesiumfrog]

Although the calendar officially defines the seasons, I remember hearing on the news that measurements of seasonal indicators (when certain types of tree start budding each year, when the first wattle flowers, when the leaves first start turning red, whatever natural phenomena you choose to observe yearly) show that "spring" is arriving a few weeks earlier these years, and that "autumn" is also moving but not as much.

 

[interested_learner]

In the US, the seasons are defined (as said eariler) as follows:

Winter: From the Winter Solstice (shortest day of the year) to the Spring Equinox (day lengths are equal).

Spring: From the Spring Equinox to the Summer Solstice (longest day of the year)

Summer: From the Summer Solstice to the Fall Equinox.

Fall: From the Fall Equinox to the Winter Solstice.

It is defined the same but is the opposite the Southern Hemisphere (June is Winter Equinox in Chile, Summer Equinox in the US).

The behavior of plants and animals will vary depending on location. The definition of season will vary as well (in Colombia, a rainy day will be termed a winter day while if the next day is sunny, it will be a summer day so go figure).

 

[russ_watters]

but how can you just say that
can you give examples or anything to give ground to that
do the behavior of plants also take such sharp turns or are tey not connected with seasons

I'm not sure you understood correctly: a "season" is just a name humans give to arbitrary time periods during the year. They don't actually mean anything - less, even, than months.

 

[cesiumfrog]

It is defined the same but is the opposite the Southern Hemisphere

Here (Australia) summer is Dec/Jan/Feb, the seasons are declared in terms of months rather than equinoxes.

 

[navneet1990]

but arent seasons supposed to be terms in a year which is described by a particular characteristic etc.
and how can you just say that from x to y is summer or winter when nature doesn't show that pattern
also how can you say that summer in the whole of northern or southern hemisphere starts or ends on the same day ??
isnt a season characterised by certain climate??
but isn't climate different in diff parts of the world?
doesnt that mean that these terms don't mean anything
but just that they are terms in a year called by such names??
and if so then there shouldn't be ANY CONNECTION BETWEEN SEASONS AND CLIMATE SHOULD THERE??

 

[jim mcnamara]

My name is jim. It's a name. If you want to imagine that I have green teeth because my name is jim, then go for it. I don't have green teeth, however.

This is what you are doing: ascribing real meaning to something based on what it is named. Summer in the Brooks Range in Alaska is not the same as Summer in Nice, France. It's just a name for part of the year, based on how high the sun gets in the sky, and conveys the idea of "warmer" in temperate zones. It has no real meaning in tropical zones - then it's monsoon (or rainy season) vs dry season.

 

[russ_watters]

but arent seasons supposed to be terms in a year which is described by a particular characteristic etc.

Yes, but the association is extremely thin and mostly arbitrary.

and how can you just say that from x to y is summer or winter when nature doesn't show that pattern

Right now, we are in a period of time many people call "Christmas vacation". It varies from one school district to another...

also how can you say that summer in the whole of northern or southern hemisphere starts or ends on the same day ??
isnt a season characterised by certain climate??

Since it is an arbitrary and largely meaningless thing, you can say whatever you want.

but isn't climate different in diff parts of the world?
doesnt that mean that these terms don't mean anything
but just that they are terms in a year called by such names??

Now you're starting to get it!

and if so then there shouldn't be ANY CONNECTION BETWEEN SEASONS AND CLIMATE SHOULD THERE??

There is a loose association. No reason why there can't be.

 

[Integral]

I personally like to break the seasons up by day length, but not on the equinox and solstice. According to the commonly accepted definitions, summer and fall are seasons of decreasing day length while winter and spring have increasing day length.

I would rather that summer represented the longest days of the year. That would put the summer solstice in the middle of summer, the Autumnal Equinox would then be in the Middle of Fall, the winter equinox in the middle of winter, etc.

The trouble then is that there is no "event" other then a change in inflection of the day length graph, to mark the change of seasons.

The definition of the seasons is completely arbitrary, feel free to come up with your own definitions, just be ready to explain your logic every time you disagree with the current calendar definitions, and do not expect to see your definition show up on calendars anytime in the future.

 

[russ_watters]

I would also shift the seasons earlier, but only by perhaps 2-3 weeks, based on the temperature in the northeast.

 

[jim mcnamara]

Climatologists use a concept of Meteorological Spring (or Summer, etc.)
for temperate zones in the Northern Hemisphere:

MSpring = March April May
MSummer = Jun July August
MFall = September October Novermber
MWinter = December January February

This matches russ watters' idea almost exactly.

 

[D H]

Russ Water's idea works well in the northeast. In south Texas, we have but two seasons: Summer and July/August.

 

[navneet1990]

ohk
thanks everyone