What is the meaning of beginning of spring in the Song Dynasty?

It means that a new cycle has begun and a new year has begun.

"beginning of spring", one of the 24 solar terms, corresponds to a certain position reached by the earth every time it runs 15 on the ecliptic, reflecting the influence of the sun on the earth, and belongs to the solar calendar category.

Beginning of spring is a time point or period. China tradition divides beginning of spring's Tenth Five-Year Plan into three periods: "The east wind thaws, the insects start to vibrate, and the fish get cold", which means that the east wind warms and the earth begins to thaw. "beginning of spring solar terms, westerly jet, the southern branch of East Asia, has begun to weaken, and the winter climate is coming to an end.

Beginning of spring is not only the first of the 24 solar terms in the Ganzhi calendar, but also in nature and people's minds, spring means mild weather, flowers and birds, and it also means the growth of everything and the sowing in spring. The so-called "one year's plan lies in spring". In climatology, spring refers to the period from 10℃ to 22℃. Speaking of beginning of spring, people obviously feel that the days are getting longer and the sun is getting warmer. Temperature, sunshine and rainfall are often at the turning point of the year and tend to rise or increase.