The primary factor that causes differences in temperature between different parts of the Earth is the angle at which the sun strikes Earth.
When the sun's rays hit the Earth at a more direct angle (as seen in the tropics), the energy is concentrated over a smaller area, resulting in warmer temperatures. Conversely, when the sun's rays strike at a more oblique angle (as seen towards the poles), the energy is spread over a larger area, leading to cooler temperatures.
While the rotation of the Earth affects day and night cycles, and the speed of Earth's orbit can influence seasonal changes, the angle of sunlight is the main reason for temperature differences across different regions. The number of cars on the road can contribute to localized warming (urban heat islands), but it does not account for the fundamental differences in temperature across larger geographical areas.
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