Why does the axis tilt cause summer?

Answer 1

Earth's tilt causes seasons based on what direction its facing the sun. The tilt allows Earth to have different seasons in different places in the world. If Earth didn't have its tilt each place would only have one season all year long.

Answer 2

Because the tilt means that the respective hemisphere is lit by the Sun more vertically at some times and these times will therefore be summer, and when the Earth tilts away from the Sun we have winter in that hemisphere. So summer in the northern hemisphere is winter in the southern.

Answer 3

Because the equator dips below the ecliptic thereby causing North America to receive more direct radiation from the sun, thereby causing a rise in temperature.