The 24 Solar Terms
The 24 solar terms are composed of 12 major (sectional) terms with each major term containing two minor (middle) solar terms. These terms represent a full orbit of the sun and split it into 24 segments, each lasting about half a month. The terms are used to mark the seasons, weather, and natural variations.
The purpose of the 24 solar terms is to provide a time frame for farmers to plan crop production and farming as well as daily life and festivals.
Solar Terms are divided according to the sun's annual motion in the ecliptic plane (the Earth's orbit around the Sun). It is part of the traditional Chinese calendar zodiac.
The 24 Solar Terms were inscribed on the Representative List of the Intangible Cultural Heritage of Humanity by UNESCO in 2016.
24 Solar Terms 2024, 2025
| Solar Terms | Chinese | Date in 2024 | Date in 2025 | Meanings |
| Start of Spring | lì chūn 立春 |
Feb. 4 | Feb. 3 | Beginning of Spring in Southern China. |
| Rain Water | yǔ shuǐ 雨水 |
Feb. 19 | Feb. 18 | Rainfall increases from then on. |
| Awakening Insects | jīng zhé 惊蛰 |
Mar. 5 | Mar. 5 | Hibernating insects start to awaken with spring thunder. |
| Spring Equinox | chūn fēn 春分 |
Mar. 20 | Mar. 20 | The mid-spring, day, and night are equally long. |
| Pure Brightness | qīng míng 清明 |
Apr. 4 | Apr. 4 | It is warm and bright (when not raining) vegetation turns green. |
| Grain Rain | gǔ yǔ 谷雨 |
Apr. 19 | Apr. 20 | Rainfall increases greatly and is helpful to grain. |
| Start of Summer | lì xià 立夏 |
May 5 | May 5 | Beginning of Summer in the South of China |
| Grain Full | xiǎo mǎn 小满 |
May 20 | May 21 | The grain gets plump but is not yet ripe. |
| Grain in Ear | máng zhòng 芒种 |
Jun. 5 | Jun. 5 | Grain grows ripe and summer farming begins. |
| Summer Solstice | xià zhì 夏至 |
Jun. 21 | Jun. 21 | It is the longest day of the year in China. |
| Slight Heat | xiǎo shǔ 小暑 |
Jul. 6 | Jul. 7 | It is hot. |
| Great Heat | dà shǔ 大暑 |
Jul. 22 | Jul. 22 | The start of the hottest time of the year and when rainfall is the greatest. |
| Start of Autumn | lì qiū 立秋 |
Aug. 7 | Aug. 7 | Beginning of Autumn |
| Limit of Heat | chù shǔ 处暑 |
Aug. 22 | Aug. 23 | Marks the end of hot days. |
| White Dew | bái lù 白露 |
Sep. 7 | Sep. 7 | Temperatures begin to drop and it turns quite cool. |
| Autumn Equinox | qiū fēn 秋分 |
Sep. 22 | Sep. 23 | Mid-Autumn, the day and night are equally long. |
| Cold Dew | hán lù 寒露 |
Oct. 8 | Oct. 8 | Turns a bit cold. |
| Frost's Descent | shuāng jiàng 霜降 |
Oct. 23 | Oct. 23 | Turns colder and frost appears. |
| Start of Winter | lì dōng 立冬 |
Nov. 7 | Nov. 7 | Beginning of Winter |
| Light Snow | xiǎo xuě 小雪 |
Nov. 22 | Nov. 22 | Starts to snow. |
| Heavy Snow | dà xuě 大雪 |
Dec. 6 | Dec. 7 | Snows heavily for the first time of the year. |
| Winter Solstice | dōng zhì 冬至 |
Dec. 21 | Dec. 21 | The shortest day of the year. |
| Slight Cold | xiǎo hān 小寒 |
Jan. 5, 2025 | Jan. 5, 2026 | Gets colder. |
| Great Cold | dà hān 大寒 |
Jan. 20, 2025 | Jan. 20, 2026 | The coldest time of the year. |
Meaning of the 24 Solar Terms
24 Solar Terms are used to reflect the changes to seasons, climate changes, and agricultural production each year.
This illustrates the wisdom of the Chinese in dividing the seasons. They influence commerce and the livelihoods of the people. These livelihoods contribute to basic human necessities (housing, food, clothing, transport) and play an important role in daily life.
Changes of Seasons
The solar terms: The Start of Spring, the Start of Summer, the Start of Autumn, and the Start of Winter reflect the changes of seasons. They divide a year into four seasons.
The Spring Equinox, Autumnal Equinox, Summer Solstice, and Winter Solstice reflect the turning point of the changes in the altitude of the sun.
Climate Changes
Slight Heat, Great Heat, Limit of Heat, Slight Cold, and Great Cold make known the temperature variations in different periods of the year.
Rain Water, Grain Rain, Light Snow, and Heavy Snow indicate the time and intensity of rainfall and snowfall.
White Dew, Cold Dew, and Frost's Descent embody the course and degree of the gradual decrease of temperature.
Natural Phenology
Grain Full, Grain in Ear, Awakening Insects, and Pure Brightness reflect the natural phenology phenomenon (the study of the timing of the biological events in plants and animals).
Origin and History of the 24 Solar Terms
As early as the Spring and Autumn Period (770-476 BC), ancient Chinese ancestors established two major solar terms: Summer Solstice and Winter Solstice, meaning "Sun North Most" and "Sun South Most," respectively.
Near the end of the Warring States Period (475-221 BC), they distinguished the four seasons: The start of Spring (Spring Equinox); the Start of Summer (Summer Solstice); the Start of Autumn (Autumnal Equinox); the Start of Winter (Winter Solstice).
Eight key solar terms were established according to the moving position of the sun and the moon at the beginning and middle of a month, and the climate and natural phenomena.
During the Western Han Dynasty (206 B.C.-24 A.D.), the twenty-four solar terms were completed and officially designated; most of them refer to the climate of Xi'an, the capital of the Han Dynasty.
The complete 24 solar terms are integrated into the Gregorian Calendar. And it continues to be used today.