Final answer:
The seasons are caused by the tilt of Earth's axis, resulting in warmer summers in the United States than winters due to direct sunlight and longer daylight duration.
Step-by-step explanation:
The seasons are caused by the 23.5° tilt of Earth's axis of rotation. This tilt causes two main effects that result in warmer summers in the United States than winters:
- Direct sunlight: During summer, the tilt of the Earth's axis causes the Northern Hemisphere to tilt towards the Sun. This means that the sunlight strikes the Earth more directly, leading to longer and more intense heating during the day.
- Daylight duration: In summer, the Northern Hemisphere receives more hours of daylight compared to winter. This allows for a longer period of heating, contributing to higher temperatures.