Greatest Time Change ?

[Airbrush]

Quick question. The length of our days is longest on the 21st of June, and shortest on the 21st of Dec. Does anyone know during what period of the cycle are the day lengths increasing (and decreasing) at the fastest rate? Are the day lengths increasing (and decreasing) at the slowest rate near the solstices, to gradually increase faster, until the days are getting longer at the fastest rate around the spring equinox? If that is true, then we should now be experiencing the most dramatic change in weather during this month.

 

Maybe this should be moved to "earth science" thanks.

 

http://en.wikipedia.org/wiki/Equinox

Edited March 12, 2015 by Airbrush

[swansont]

The longest day is in the latter part of December; we are at perihelion in early January. ~21 June has the most daylight hours (in the northern hemisphere), but that's not the same thing.

 

http://earthsky.org/tonight/longest-days-of-year-accompany-the-december-solstice

 

Here's the length of day in 2009

http://www.pierpaoloricci.it/dati/giornosolarevero_eng.htm

[Airbrush]

"Greatest Time Change" is a bad title. It should be "Daylight Hours Rate Change". My concern is daylight hours and how it impacts our weather. Daylight hours are increasing everyday after Dec 21st in the N hemi but my guess, that I cannot confirm, is the rate of increase of daylight hours increases at the fastest rate near the equinox, centered on 20 March. The total amount of daylight length change during March (and September) is equivalent to all the months before or after. For this reason the equinoxes should be the time of most dramatic weather change, from cold to hot, and back again, except maybe the poles.

Edited March 14, 2015 by Airbrush

[swansont]

The rate of change of daylight hours will depend on the latitude. So pick a location, and you can make a table, and figure it out

 

http://aa.usno.navy.mil/data/docs/Dur_OneYear.php