Explanation:
The earth is tipped on its axis, 23.5 degrees in respect to the sun. In the summer time, the northern hemisphere has slightly more hours of daylight because of this, becoming more extreme as one goes north. If you go far enough north, there is 24 hours of sunlight in high summer.
So the average temperature is higher, because there is sunlight is present for more hours and the earth is warmed on balance.
At the same time, the south pole is in shadow, so the southern hemisphere has winter in June.
Six months later, the 23.5 degree tilt has the north pole facing away from the sun, and with fewer daylight hours, the temperature cools progressively. Meanwhile, the southern hemisphere is having it’s summer in December.
