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I have heard of years with longer summers and winters and shorter springs and falls and vice versa because of a change in the earths axis.
Is this from the procession that causes the season switch every 25,800 years or is it from some other change in the earth's axis like angle change and not revolution at the same angle(which I think the procession is)?
You seem to have two types of seasons confused. Astronomical seasons are relatively stable in their durations, while seasons as defined by the weather, can vary by several weeks. For example, snow 3 weeks after spring begins or freezing weather before winter begins. This is what is meant when we say an early summer or a late winter. It simply means that the weather usually associated with that season is later or earlier than usual.
Generally, the lengths of the seasons ranges from about 88 to 93 days every year.
For 2014 (Northern hemisphere season lengths) Length of spring = 92d 17h 54m Length of summer = 93d 15h 37m Length of autumn = 89d 20h 34m Length of winter = 88d 23h 42m
The axis of the earth has nothing to do with it unless we are considering a time span extending to many thousands of years. The Earth's axis hasn't changed enough in recorded history to significantly effect the seasons.
The astronomical seasons are defined by the geocentric position of the sun and have little to do with the weather.
March Equinox
Beginning of spring in the northern hemisphere = Beginning of autumn in the southern hemisphere, when the sun reaches declination 0 degrees while crossing the celestial equator northward.
June Solstice
Beginning of summer in the northern hemisphere = Beginning of winter in the southern hemisphere, when the sun reaches right ascension 90 degrees (6h).
September Equinox
Beginning of autumn in the northern hemisphere = Beginning of spring in the southern hemisphere, when the sun reaches declination 0 degrees while crossing the celestial equator southward.
December Solstice
Beginning of winter in the northern hemisphere = Beginning of summer in the southern hemisphere, when the sun reaches right ascension 270 degrees (18h).
These astronomical season lengths vary by only a matter of minutes either way each year, while the seasonal weather can vary considerably and winter-type weather can persist even after astronomical spring has begun (a late or short spring), but it is not yearly changes in the axis of the Earth that causes these annual weather variations.
SEASONAL STATISTICS FOR THE YEAR 2014 @ TZone = UT-05:00 (New York City) BEGINNING DATES, TIMES TT AND LENGTHS OF THE SEASONS AND SEASONAL YEARS Equinox or Solstice Season Length Since Previous Until Following E 2014 Mar 20 11:57:58 92d 17h 54m 23s 365d 05h 54m 51s 365d 05h 48m 15s S 2014 Jun 21 05:52:21 93d 15h 37m 26s 365d 05h 47m 17s 365d 05h 46m 41s E 2014 Sep 22 21:29:47 89d 20h 34m 21s 365d 05h 44m 56s 365d 05h 52m 40s S 2014 Dec 21 18:04:08 88d 23h 42m 05s 365d 05h 52m 01s 365d 05h 44m 56s
Perhaps these links will help:
http://neoprogrammics.com/equinoxes_and_solstices/
http://neoprogrammics.com/equinoxes_and_solstices/seasonal_statistics/
I think there is a cycle where the inclination of the axis of earth also changes periodically. This is different than precession where the orientation of the axis changes and not the inclination. That will cause the season length change. Also there are Interstellar clouds through which the solar system passes. Which reduces the solar radiation reaching earth. They are responsible for Ice ages.
