While the North is celebrating the start of summer in June, the Southern Hemisphere is entering winter. June 21 marks their winter solstice. In regions like Australia, South Africa, and Argentina, the "festive season" in December occurs during the height of summer. The summer solstice for the South falls on December 21, meaning Christmas is often associated with beach trips and barbecues rather than snow and fireplaces.
The most fundamental rule of seasons is the mirror effect. The Northern and Southern Hemispheres always experience opposite seasons simultaneously. seasons by hemisphere
: As Earth orbits, the North Pole tilts toward the Sun in June (Summer in the North) and away in December (Winter in the North). While the North is celebrating the start of
Because the sun is always high in the sky near the equator, these regions enjoy warm, summer-like weather year-round. The summer solstice for the South falls on
The single most important factor governing seasons is the of Earth relative to its orbital plane around the Sun.