This source calculates all of the sun parameters based on date and location. Feed the intensity information to your dimmer(s) to simulate the solar cycle. With some spectral control (not currently in the code) you could get pretty close to simulating the effect of far reds in the mornings and evenings.
Combine with this:
… and you can calculate the amount of solar irradiation for at any point in time for any location in the world or integrate over the day to obtain the DLI.
The source doesn’t have anything to simulate weather, though. Which, by the way, there is some research I’ve seen out there that details experiments on the effect of varying sunlight intensities. I can’t recall the conclusions.
Sample using the code to generate a DLI map for the world throughout the year:
