Spring! Celebration One

Environmental & Science Education
STEM
Earth Science
Earth Systems
Astronomy
Edward Hessler

Spring! Today? Yep!

It depends on who is defining it.

Meteorologists/climatologists or astronomers.

March 1 is Meteorological Spring, the season lasts for three months, then Meteorological Summer arrives on June 1, Meteorological Fall on September 1 and Meteorological Winter on December 1. Astronomical Spring/Spring or Vernal Equinoix arrives March 20, 11:15 am in St. Paul, MN (Celebration Two).

For some of us events that count have been the return of light about a month ago and now heat.

Astronomers define spring as the time when the sun is directly over the equator. Meteorologists and climatologists came to prefer calendar months as explained by the National Oceanic and Atmospheric Administration (NOAA). 

Meteorological observing and forecasting led to the creation of these seasons, and they are more closely tied to our monthly civil calendar than the astronomical seasons are. The length of the meteorological seasons is also more consistent, ranging from 90 days for winter of a non-leap year to 92 days for spring and summer. By following the civil calendar and having less variation in season length and season start, it becomes much easier to calculate seasonal statistics from the monthly statistics, both of which are very useful for agriculture, commerce, and a variety of other purposes.

Here is a fact sheet on differences between the two seasons including a diagram that may have confused you in school, perhaps still does. There are also a variety of links.

Happy Springs, #1 and #2.