When Do Seasons Start Page

Trenberth, K. E. (1983). "What are the seasons?" Bulletin of the American Meteorological Society , 64(11), 1276–1282. https://doi.org/10.1175/1520-0477(1983)064<1276:WATS>2.0.CO;2

It is important to remember that seasons are opposite depending on which hemisphere you are in. When the Northern Hemisphere is tilted toward the sun (Summer), the Southern Hemisphere is tilted away (Winter).

Here’s a useful and well-cited paper that directly addresses the question of when seasons start, including both astronomical and meteorological definitions, as well as phenological and climatic perspectives: when do seasons start

The change of seasons is one of nature’s most predictable yet transformative rhythms. However, if you’ve ever wondered why the "official" start of spring or winter doesn’t always match the weather outside, it’s because there are two different ways to measure the calendar: and meteorological .

This system makes it much easier to calculate seasonal statistics and aligns better with how we actually experience the weather. March 1 – May 31 Summer: June 1 – August 31 Autumn: September 1 – November 30 Winter: December 1 – February 28 (or 29) Trenberth, K

You might notice that the astronomical start dates vary by a day or two each year. This happens for two main reasons:

Menzel, A., & Fabian, P. (1999). "Growing season extended in Europe." Nature , 397(6721), 659. "What are the seasons

Meteorologists and climatologists use a different system. Instead of looking at the stars, they look at the thermometer. They break the year into four three-month periods based on the annual temperature cycle.