How does the earth's orbit effect the weather?
Sunlit hemisphere of the spinning Earth oscillates up and down the ecliptic, with period one year, due to the inclination 23.4 deg inclination of the polar axis to the normal of the Ecliptic.
The Earth orbits around the Sun with period 1 year and spins about its polar axis with period 1 day. Obviously, overhead-Sun- noon location on the Earth is not fixed. It is moving. Accordingly, the sunlit-hemisphere is also changing..Latitude-wise. Its center oscillates between 23.4 deg S to 23.4 deg N. The changes in weather/climate are primarily attributed to these aspects of the orbital motion of the Earth, and also, the inclination of the spin axis..