Growing degree days

Bernadette Roche BRoche at LOYOLA.EDU
Wed Dec 9 14:09:02 EST 1998

Growing degree days and heating degree days used to confuse me too!  I figured they should go in the same direction, but they don't!  This is because heating degree days are a measure of how much you have to heat your house to keep it at a reasonable temperature - this value gets HIGHER the COLDER it is outside.  On the other hand, growing degree days are a measure of how quickly an organism can develop, based on the external temperature, and this value gets higher the WARMER it is outside.  

Gee, I hope I'm right about this!!  It came to me in an epiphany once while I was listening to the ag report.


Bernadette Roche
Department of Biology
Loyola College
4501 N. Charles St. 
Baltimore, MD 21210
broche at

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