A look at temperatures last summer

Depending where you are in the world, and how you like to think of summer, there are different ways to define the start and end of summer. For places where it gets warm enough, I like to use growth potential (GP) as a way to define the duration of time when cool-season GP is lower than warm-season GP. That is, the ΔGP obtained by taking the cool-season GP for a day, and subtracting the warm-season GP for that same day,…