Solar Calendar, Clock, Variable Time Intervals
Four seasons as a calendar, specific to coordinates. Days are independent from seasons. A day interval is dependent on when dawn and dusk occurs.
this is a sun graph for Inuvik Canada which is in the arctic circle. The area around June would be consider a single day.
Dawn, dusk, middle.
The interval of a "second" to be variable to duration of sunlight, night. Maybe divide the duration by 10,000.