When do the seasons start and end?
Did you know that seasons are not the same for everyone? Have you ever heard of the six-season calendar?
Yes, the dates of when spring, summer, fall/autumn, and winter begin and end depend on anyone's perspective and nationality.
It is fair to recognize, though, that each season has its specific weather pattern, average air temperature, and length of daylight; nature also changes accordingly.
However, seasons aren't the same for meteorologists, astronomers, people living in the northern and southern hemispheres, and south asian citizens. But why is that the case?
The most widely used civil calendar in the planet is the Gregorian calendar. And for a large number of countries that have adopted them, the beginning and end of seasons take place based on astronomical timings.
As a result, nowadays, the most common equinox and solstice dates are March 20 (spring), June 21 (summer), September 22 or 23 (fall/autumn) and December 21 (winter). That's the four-season calendar.
However, when it comes to defining the beginning and the end of seasons, not all countries adopt a universal standard. You'll find northern and southern hemisphere nuances, as well as regional and national differences.
In Australia and New Zealand, each season starts on the first day of the calendar month. They follow the meteorological method - as opposed to the astronomical method adopted in North American and Europe - based on surface air temperatures.
In South Asia, the scenario changes dramatically. Many nations adopt a six-season calendar which comprises of spring, summer, monsoon, autumn, early winter/late autumn, and late winter/winter.
Last but not least, a few tropical countries adopted two seasons: the monsoon, wet or rainy season, and the dry season.
In conclusion, only North America and Europe set a Universal Time (UT) for the start and end of their four seasons, even if it has to be realigned occasionally in leap years.
Seasons Throughout the World | Start and End Dates (2017/2018)
North America & Europe (Except Russia and Ireland)
Spring: March, 20 (10:28 am) > April 21 (04:23 am)
Summer: June, 21 (04:24 am) > September 22 (08:01 pm)
Fall/Autumn: September, 22 (08:02 pm) > December 20 (04:27 pm)
Winter: December 21 (04:28 pm) > March 19 (04:14 pm)
Ireland & Russia
Spring: March, 1 > May, 31
Summer: June, 1 > August 31
Fall/Autumn: September, 1 > November 30
Winter: December 1 > February 28/29
Australia & New Zealand
Spring: September, 1 > November 30
Summer: December, 1 > February 28/29
Fall/Autumn: March, 1 > May 31
Winter: June, 1 > August 31
Spring (Vasanta): Mid-March > Mid-May
Summer (Greeshma): Mid-May > Mid-July
Monsoon (Varsha): Mid-July > Mid-September
Autumn (Sharad): Mid-September > Mid-November
Early Winter (Hemanta): Mid-November > Mid-January
Late Winter (Shishira): Mid-January > Mid-March
Spring (Bosonto): Mid-February > Mid-April
Summer (Grishmo): Mid-April > Mid-June
Monsoon (Borsha): Mid-June > Mid-August
Autumn (Shorot): Mid-August > Mid-October
Late Autumn (Hemonto): Mid-October > Mid-December
Winter (Sit): Mid-December > Mid-February