Since summer (and other seasons) can begin and end on different days each year on the astronomical calendar, it can be hard to compare seasons from year to year in this way. To standardize the length and start of the seasons, in meteorology, the 12 months of the year have been split up into four, 3-month periods. Therefore, in the meteorological calendar, summer includes the months of June, July and August - always starting on 1 June and ending on 31 August.
NADPH or NADP plus stands for Nicotinamide Adenine Dinucleotide Phosphate. NADPH is created in the Stoma on the duration of light reactions accumulation. NADPH or NADP plus stands for Nicotinamide Adenine Dinucleotide Phosphate. NADPH is created in the Stoma on the duration of light reactions accumulation.
What is obvious from that is the connection to the light reactions. The Calvin cycle needs NADPH and ATP from the light reactions. Thus the Calvin cycle is inseparable from the light reactions...they only occur in the light! This is why dark reactions is a poor name for the Calvin cycle. This relationship with the light reactions is reciprocal...the light reactions need a supply of ADP, P i, and NADP + which come directly from the Calvin cycle: