> > Hopefully someone has figured out how to construct correct cumulative > (over the season!) growing degree day graphs, too. >
Here is the "cooling-degree-day" table: Degree Day (°C) Table \ Min Daily Temp Max 0 2 4 6 8 10 12 14 16 18 20 22 24 26 28 30 32 9 0 0 0 0 0 *** *** *** *** *** *** *** *** *** *** *** *** 11 0 0 0 0 0 0 *** *** *** *** *** *** *** *** *** *** *** 13 0 0 0 0 0 1 2 *** *** *** *** *** *** *** *** *** *** 15 0 0 0 0 1 2 3 4 *** *** *** *** *** *** *** *** *** 17 0 0 0 1 2 3 4 5 6 *** *** *** *** *** *** *** *** 19 0 0 1 2 3 4 5 6 7 8 *** *** *** *** *** *** *** 21 0 1 2 3 4 5 6 7 8 9 10 *** *** *** *** *** *** 23 1 2 3 4 5 6 7 8 9 10 11 12 *** *** *** *** *** 25 2 3 4 5 6 7 8 9 10 11 12 13 14 *** *** *** *** 27 3 4 5 6 7 8 9 10 11 12 13 14 15 16 *** *** *** 29 4 5 6 7 8 9 10 11 12 13 14 15 16 17 18 *** *** 31 5 6 7 8 9 10 11 12 13 14 15 16 17 18 19 20 *** 33 6 7 8 9 10 11 12 13 14 15 16 17 18 19 20 20 20 35 7 8 9 10 11 12 13 14 15 16 17 18 19 20 20 20 20 37 8 9 10 11 12 13 14 15 16 17 18 19 20 20 20 20 20 39 9 10 11 12 13 14 15 16 17 18 19 20 20 20 20 20 20 41 10 11 12 13 14 15 16 17 18 19 20 20 20 20 20 20 20 43 11 12 13 14 15 16 17 18 19 20 20 20 20 20 20 20 20 45 12 13 14 15 16 17 18 19 20 20 20 20 20 20 20 20 20 47 13 14 15 16 17 18 19 20 20 20 20 20 20 20 20 20 20 49 14 15 16 17 18 19 20 20 20 20 20 20 20 20 20 20 20 Cooling-degree-days is the average temperature less a threshold temp. It can be clipped to a maximum. ... and here is the "growing-degree-day" table: Degree Day (°C) Table \ Min Daily Temp Max 0 2 4 6 8 10 12 14 16 18 20 22 24 26 28 30 32 9 0 0 0 0 0 *** *** *** *** *** *** *** *** *** *** *** *** 11 0 0 0 0 0 0 *** *** *** *** *** *** *** *** *** *** *** 13 0 0 0 0 1 1 2 *** *** *** *** *** *** *** *** *** *** 15 1 1 1 1 1 2 3 4 *** *** *** *** *** *** *** *** *** 17 1 2 2 2 2 3 4 5 6 *** *** *** *** *** *** *** *** 19 2 2 3 3 3 4 5 6 7 8 *** *** *** *** *** *** *** 21 3 3 4 4 4 5 6 7 8 9 10 *** *** *** *** *** *** 23 4 4 4 5 5 6 7 8 9 10 11 12 *** *** *** *** *** 25 5 5 5 6 6 7 8 9 10 11 12 13 14 *** *** *** *** 27 6 6 6 7 7 8 9 10 11 12 13 14 15 16 *** *** *** 29 7 7 7 8 8 9 10 11 12 13 14 15 16 17 18 *** *** 31 7 8 8 9 9 10 11 12 13 14 15 16 17 18 19 20 *** 33 8 8 9 9 10 11 12 12 13 14 15 16 17 18 19 20 20 35 9 9 9 10 10 11 12 13 14 15 16 17 17 18 19 20 20 37 9 9 10 10 11 11 12 13 14 15 16 17 18 18 19 20 20 39 9 10 10 11 11 12 13 14 15 15 16 17 18 19 19 20 20 41 10 10 10 11 11 12 13 14 15 16 16 17 18 19 19 20 20 43 10 10 11 11 12 12 13 14 15 16 17 17 18 19 19 20 20 45 10 11 11 11 12 13 13 14 15 16 17 17 18 19 19 20 20 47 10 11 11 12 12 13 14 14 15 16 17 18 18 19 19 20 20 49 11 11 11 12 12 13 14 15 15 16 17 18 18 19 19 20 20 As you can see, Growing-Degree-Days (GDD) is warmer for cool temps and cooler for warm temps. I believe the calculation for GDD can be as complicated as you want to make it. It is the area under a symmetric sine wave of daily temps above a threshold temp, but it's clipped above, too. Whether you assume growth continues at a constant rate above the ceiling or stops altogether means you use different formulas. My formula assumes growth continues unaffected by temperature, which is considered appropriate for some but not all insect species. Yes, I can show you a graph of cumulative GDD. Please take a look at my weeWX extension <http://lacusveris.com/cydia/index.shtml> for codling moth. Thanks. -ccr- -- You received this message because you are subscribed to the Google Groups "weewx-user" group. To unsubscribe from this group and stop receiving emails from it, send an email to [email protected]. For more options, visit https://groups.google.com/d/optout.
