East Asia: Water deficits in SE China will shrink

21 December 2021

THE BIG PICTURE
The 12-month forecast for East Asia through August 2022 indicates widespread severe to exceptional water surpluses in Northeast China in the Songhua River Watershed extending across the Russian border. This vast path of intense surplus will continue south through the North China Plain and the Yellow River (Huang He) Watershed.

In the Yangtze River region, surpluses will be widespread in the northern portion of the basin. Anomalies will be moderate in the river’s lower watershed, and exceptional along much of its middle path and in the drainage basin of Three Gorges Dam. Surpluses will also be exceptional along the Han River, a northern tributary of the Yangtze. Much of Tibet (Xizang) will see surpluses, exceptional tracing the Yarlung (Brahmaputra) River.

Widespread, intense deficits are forecast from western Inner Mongolia into northern Gansu and across the breadth of Xinjiang (Uygur). In Southeast China, deficits are forecast in Jiangxi, Guangdong, and Fujian, and a few small pockets in west-central Taiwan. Deficits are also expected in northern Yunnan though surpluses are forecast in the center of the province and southeast.

On the Korean Peninsula, surpluses will be widespread in the north with extreme anomalies in the northeast. Surpluses are also forecast in pockets of southern Japan, but intense deficits are expected in Hokkaido. In Mongolia, surpluses are forecast in the north, east, and in the central Hangayn Mountains. Deficits are forecast in the western Gobi Desert and near Dund-Us in the nation’s northwest.

FORECAST BREAKDOWN
The 3-month time series maps below show the evolving conditions in more detail.

The forecast through February 2022 indicates persistent, widespread, extreme to exceptional surpluses from Northeast China through the North China Plain and much of the vast Yellow River Basin. In the Yangtze River region, surpluses will be widespread and intense in the northern portion of the basin from the Gorges into central Sichuan, moderate in the river’s lower basin, while mixed conditions are expected in the far upper reaches. Deficits in Southeast China will shrink, persisting with intensity in Guangdong. Deficits are also forecast at the intersection of Chongqing and Hunan, and from northern Yunnan into Sichuan. Surpluses are forecast in central Yunnan and throughout most of Tibet. Widespread surpluses in North Korea will intensify, becoming exceptional. Hokkaido, Japan will begin to transition from deficit to surplus. Near-normal conditions are forecast for the remainder of Japan with some deficits in southeastern Honshu. In Mongolia surpluses are forecast in the north, east, and down the center of the country through the Hangayn Mountains, and deficits in the west.

From March through May 2022, widespread surpluses will persist in China in a distribution pattern like the prior three months, but anomalies will nearly disappear in the Lower Yangtze Basin, will moderate in central Sichuan and southern Gansu, and will downgrade to mild in the Gorges region. In Southeast China, deficits will nearly disappear. Severe deficits will increase in northern Yunnan and into eastern Tibet, while surpluses persist in central Yunnan. Deficits are forecast in western Inner Mongolia, central Xinjiang, and southern Mongolia. In North Korea, surpluses will shrink considerably, persisting in pockets of the northeast. Severe deficits will emerge in northern in Honshu.

The forecast for the final three months – June through August 2022 – indicates that surpluses will shrink and downgrade considerably in China but persist in the northeast, the Yellow River Watershed, and western Tibet. Deficits are forecast in western Inner Mongolia, Xinjiang, and from northern Yunnan into Tibet.

Please note that WSIM forecast skill declines with longer lead times.

IMPACTS
Drought in South China’s Guangdong Province has prompted officials to urge cities throughout the province to reduce water use. Shenzhen, the region’s tech hub, is experiencing its worst drought in four decades. The city’s water authority is projecting shortfalls through spring of 1 million cubic meters (264 million gallons) per day. Shenzhen gets 90 percent of its water from the Dongjiang River, a tributary of the Pearl, and Hong Kong relies on the river for about 70 percent of its water.

Global risk assessment by Aon calculates economic losses of CNY6.9 billion (US$1.1 billion) resulting from successive winter weather events in northern China during November.

NOTE ON ADMINISTRATIVE BOUNDARIES
There are numerous regions around the world where country borders are contested. ISciences depicts country boundaries on these maps solely to provide some geographic context. The boundaries are nominal, not legal, descriptions of each entity. The use of these boundaries does not imply any judgement on the legal status of any territory, or any endorsement or acceptance of disputed boundaries on the part of ISciences or our data providers.

Subscribe to our monthly Water Watch List

Search blog categories

Search blog tags