Introduction: The "24 Solar Terms" is a knowledge system and social practice developed by the Chinese through observing the annual movement of the sun. This system reflects the changes in seasons, climate, and phenology throughout the year. The 24 Solar Terms guide traditional agricultural production and daily life, forming an essential part of China's traditional calendar system and related practices. In 2006, the "24 Solar Terms" was listed in the first batch of the National Intangible Cultural Heritage Representative List.
Origins and Development: The 24 Solar Terms originated in the Yellow River basin and are a crucial part of the Chinese lunar calendar, a lunisolar calendar. The calendar divides the sun's annual movement into 24 segments, standardizing the Solar Terms. The sun's movement along the ecliptic is divided into 24 equal parts, each representing a Solar Term. As the sun moves 15 degrees along the ecliptic, it completes one Solar Term. With 360 degrees in a year, there are 24 Solar Terms in total, with two Solar Terms each month. The first Solar Term each month is called a "major term," such as the Beginning of Spring (Lichun), Awakening of Insects (Jingzhe), and Clear and Bright (Qingming). The second Solar Term each month is called a "minor term," such as Rain Water (Yushui), Spring Equinox (Chunfen), and Grain Rain (Guyu). These terms alternate, each lasting about 15 days, and are now collectively known as the "Solar Terms."
Observation and Calculation: The recording of the 24 Solar Terms evolved from direct observations of terrestrial and celestial phenomena to the use of instruments for accurate calculations. Initially based on simple observations, the process gradually advanced to include tools for precise measurements. The Solar Terms originated from observing the periodic changes in the weather, temperature, precipitation, and phenological events in the Yellow River basin. These observations provided a reliable time guide for agricultural societies and were gradually adopted nationwide, shared among multiple ethnic groups. As a unique Chinese time-knowledge system, this heritage project profoundly influences people's thinking and behavioral norms, serving as a significant carrier of cultural identity for the Chinese nation.
Cultural Significance: The 24 Solar Terms are a rich intangible cultural heritage, encompassing proverbs, songs, legends, traditional production tools, daily utensils, and artistic works such as crafts, paintings, and calligraphy. They also include festival cultures, production rituals, and folk customs closely linked to the Solar Terms. While the practical agricultural guidance of the 24 Solar Terms has diminished with urbanization and modern agricultural techniques, it continues to hold cultural and social significance in contemporary Chinese life. It reflects the Chinese respect for nature, adherence to natural laws, and sustainable development. The Solar Terms showcase the unique Chinese understanding of the cosmos and natural world, their harmonious relationship with nature, and their creativity. This heritage is a vivid testament to the cultural diversity of humanity.
