The PPFD (photosynthetic photon flux density) every 5 minutes for a day, week, month, and year at Corvallis looks like this. I’m not so interested in the PPFD when the temperatures are too cold or too hot for photosynthesis. I selected only those times in 2014 when the C3 growth potential (GP) was greater than or equal to 0.5 (on a scale of 0 to 1), and the PPFD by time of day looks like this:

PPFD in 2014 when GP >= 0.5

What happens when there is shade in the morning that blocks 80% of the PPFD, from sunrise until 2 hours before solar noon? What does the PPFD by time of day look like then?

PPFD in 2014 in Corvallis when GP >= 0.5 and 80% shade is imposed until 2 h before solar noon