The primary reason for winter being colder than summer is the tilt of the Earth's axis relative to its orbit around the Sun. This tilt causes variations in the intensity and duration of sunlight received by different parts of the Earth throughout the year, leading to the changing seasons.
During summer, the hemisphere tilted towards the Sun receives more direct sunlight, resulting in longer days and shorter nights. The Sun's rays are more concentrated, leading to higher solar energy input. This increased solar energy heats up the Earth's surface, resulting in warmer temperatures.
In contrast, during winter, the hemisphere tilted away from the Sun receives sunlight at a lower angle, leading to shorter days and longer nights. The sunlight is spread out over a larger area, reducing its intensity and resulting in lower solar energy input. This decreased solar energy leads to cooler temperatures.
It's important to note that the specific weather patterns and temperature variations experienced during winter and summer are also influenced by other factors such as ocean currents, atmospheric circulation patterns, and local geography. These factors can modify the overall temperature patterns in different regions.