PENNSYLVANIA, USA — Summer has flown by, winding down to its unofficial end on Labor Day weekend. While it may have felt short, it may not be the shortest season.
Depending on who you ask, summer ends on different days based on different definitions of the seasons.
THE QUESTION
Are all four seasons the same length?
OUR SOURCES
Juniata College Professor of Physics and Astronomy Dr. Matthew Beaky.
WHAT WE FOUND
There are two ways to define the seasons: meteorologically and astronomically. Dr. Beaky says both systems are correct, even though they are not identically aligned.
"The Earth goes in orbit around the sun, it reaches four special points, we call it equinoxes and solstices. And the equinox or solstice marks the beginning of that particular astronomical season," Beaky said. "Meteorological seasons are more aligned with the weather patterns we experience with the climate."
The National Centers for Environmental Information says meteorological seasons are broken up into four sets of three months and vary by one to two days. Here is the breakdown:
Spring: March, April, and May
Summer: June, July, and August;
Fall: September, October, and November
Winter: December, January, and February.
Astronomical seasons can vary by up to four days, usually between 89 and 93 days in total. They are less uniform due to the Earth’s orbit.
"Because the Earth is closer to the Sun in January, moving a bit faster, the six months around winter are much shorter than the six months in the summer when the earth is moving more slowly in its orbit," Dr. Beaky said.
This means winter is the shortest and summer is the longest, though only by a few days.
So no, the seasons that we feel are not the same length.
Still, the two seasonal measurements stay relatively in sync thanks to our calendar
"The system of LEAP days that we have now is specifically designed to make sure that our calendar realigns with the seasons," Dr. Beaky said.
Without a leap day every four years, the meteorological seasons would become out of sync with the astronomical solstices and equinoxes.