The origin of the start of autumn

"In the third phase cry the cicadas". With sufficient food and convenient temperature, cicadas cry pleasantly on trees, as if they are informing us the departure of summer. Start of Autumn is all together 15 days long, 5 days in each phase. The Start of Autumn is when the weather starts to become cool.

When Start of Autumn begins, many places in China are still very hot. Although it may remain hot for some time even after the Start of Autumn, the weather tends to cool down. The difference in temperature between the day and the night becomes more and more obvious. However, due to the diversity of climate throughout the country, the true starting time of autumn differs.

In reality, there are many ways to mark the beginning of autumn: according to solar terms, the Start of Autumn symbolizes the beginning of autumn; in astronomy, it is the Autumn Equinox which is figured out by the orbit in which the Earth revolves around the Sun; given climatic statistical data, autumn begins from September and judging from the daily average temperature, the first day of the successive five days in which the daily average temperature is between 10℃ and 22℃ is considered the initial day of autumn.

As mentioned before, owing to the geographical difference between the northern and southern China, not all the places in China enter autumn at the same time. In mid August, Heilongjiang province and north Xinjiang Uygur autonomous region meet autumn earlier than any other parts of China. Normally, autumn will arrive in northern China in early September and in the southwest part and Qinhuai area in mid September. In October, it reaches the Jiangnan and then Lingnan areas. In mid November autumn moves to Leizhou Peninsula and north Hainan Island at a leisurely pace, and when autumn eventually comes to Sanya City, it is almost New Year’s Day.