Question

Seasonality is affected by what geographical occurrences

Answer 1

Basically you need to ask: how long are the seasons? The seasons rotate on a yearly basis, which corresponds to the Earth's rotation around the Sun - so the major cooccurence is the Earth's rotation around the Sun, combined with the change in the tilt of the Earth's axis. 

This in turn influences the currents and the precipitation, which more directly cause the change of the seasons. 

Answer 2

Seasonality is affected by the temperature in the air, often in conjunction with the time of the year. Worldwide common seasons are winter, spring, summer, and autumn. However, many places also note seasons factoring in precipitation levels, calling them the wet (rainy) season and the dry (not rainy) season.