Yibin

Yibin (; Sichuanese Pinyin: ȵi²bin¹; Sichuanese pronunciation: ) is a prefecture-level city in the southeastern part of Sichuan province, China, located at the junction of the Min and Yangtze Rivers. Its population was 4,588,804 inhabitants, according to the 2020 census, of whom 2,158,312 lived in the built-up area comprising three urban districts.

History

Human habitation of Yibin dates back at least 4,000 years. At that time, this place was one of the important birthplaces of ancient Bashu culture. Yibin was established as a county in the Han dynasty (206 BC − AD 220). Under the Ming and Qing, the town and its hinterland was known as Xuzhou Commandery (), which was variously romanized as Suifu, Suifoo, Xufu, and Suchow. In 1907, its population was estimated to be 50,000.

Geography and climate

thumb|left|The Yangtze at the confluence of the Min and [[Jinsha River|Jinsha Rivers. Below Yibin, the Yangtze is known in Chinese as Chang Jiang or the "Long River". Above Yibin, the Yangtze is known as the Jinsha or Gold Sands River.]]

thumb|Map including Yibin (labeled as I-PIN (SUIFU) ) ([[Army Map Service|AMS, 1954)]]

Yibin is located in the southeast portion of Sichuan at the southern end of the Sichuan Basin, bordering Zhaotong (Yunnan) to the south, Luzhou to the east, Liangshan Yi Autonomous Prefecture and Leshan to the west, and Zigong to the north, and has a total area is . The city ranges in latitude from 27° 50'−29° 16' N, and in longitude from 103° 36'−105° 20' E, stretching east-west and north-south.

The city is located at the confluence of the Min and Yangtze Rivers. Above Yibin, the Yangtze is also known as the Jinsha River. Below Yibin, the Yangtze is known in Chinese as the Chang Jiang or "Long River."

As with the rest of the Sichuan Basin, Yibin has a monsoon-influenced humid subtropical climate (Köppen Cwa) with high humidity year-round; winters are short and mild while summers are long, hot, and humid. The monthly 24-hour average temperature ranges from in January to in July and August; the annual mean is . Despite its location in the Yangtze River valley, it is still cooler than Chongqing, located further downstream, in its warmest months. Frost is uncommon and the frost-free period lasts 347 days. Rainfall is common year-round but is the greatest in July and August, with very little of it in the cooler months. With monthly percent possible sunshine ranging from 10% in December and January to 42% in August, the city receives only 1,018 hours of bright sunshine annually; Yibin has one of the lowest annual sunshine totals nationally, lower than even nearby Chengdu and Chongqing. Spring (March–April) tends to be sunnier and warmer in the day than autumn (October–November). Extremes in Yibin since 1951 have ranged from on January 3, 1962 to on August 25, 2022.