Extreme day and night phenomenon of solar terms

Extreme night, June, July and August around the summer solstice are summer months in the northern hemisphere. The farther north the summer days are, the more extreme days will appear in the Arctic.

Every year, "extreme day" and "extreme night" appear alternately in the north and south poles. In a year, six consecutive months are daytime (called extreme daytime) and six months are dark (called extreme night). The time of day and night alternation changes with the increase of latitude. The higher the latitude, the longer the extreme day and night.

Extended data

After the vernal equinox, there will be extreme days near the North Pole, and then the range of extreme days will become larger and larger; It reaches its maximum on the solstice in summer, and the boundary reaches the Arctic Circle. After the summer solstice, the extreme daily range near the North Pole is gradually reduced, and it is reduced to zero by the autumn equinox.

After the autumnal equinox, extreme days appeared near the South Pole, and then the range of extreme days near the South Pole became larger and larger. It reaches its maximum in the winter solstice, and the boundary reaches the Antarctic circle; From winter to the future, the extreme daily range near the South Pole gradually decreases, and it decreases to zero by the vernal equinox.