East Asia: Water deficits will continue to emerge in northeast China & Korea

26 June 2017

The Big Picture
The 12-month forecast map for East Asia (below) indicates that some extreme to exceptional deficit conditions are expected in western Mongolia, north-eastern China, and the central Korean Peninsula. Moderate to severe deficit conditions are expected from northern Gansu Province extending into Xinjiang, through much of Guizhou, and across most of Japan.

Recent surpluses continue in central Tibet and in select areas of western Xinjiang Province.

Impacts
A massive landslide triggered by heavy rain has buried more than 120 people with 15 confirmed dead in southwest China's Sichuan Province. Officials estimate that around 18 million cubic meters of earth - enough to fill 3,000 Olympic swimming pools - fell 1,600 meters (1 mile), engulfing Xinmo Village in mountainous Aba Prefecture. More than 1,000 workers are searching for survivors of the landslide which blocked a 2-km (1.2 mile) section of river and covered 1.6 km (1 mile) of road.

Torrential rainfall has caused flooding in Hunan and Hubei Provinces, affecting 390,000 people. Recorded at 160mm (6.3 inches) in one day in some places, the rain triggered power outages in 30,000 households and caused 73 reservoirs to overflow. Over 9,000 people were evacuated, at least 46 homes destroyed, and 4,660 hectares of cropland (11,515 acres) damaged.

Drought in northeast China has created a shortage of drinking water for 120,000 people and 500,000 livestock, and has affected 2.67 million hectares (11.5 million acres) of farmland. China's agriculture ministry reduced the 2017/2018 corn output forecast to 3.6 percent lower than last year, making it the smallest since 2013, according to China National Grain and Oils Information Center. The drought made it difficult for farmers to plant corn, forcing many to switch to soybeans and grains. In late May, China earmarked 485 million yuan (US$70.7 million) for drought relief in the north and post-earthquake reconstruction in the west.

Forecast Breakdown
The 3-month time series maps show the evolving conditions in more detail.

Recent deficits in eastern Mongolia and around the Bohai Sea are forecast to moderate over the coming months but those in central Korea covering the Incheon and Seoul region are expected to persist through the June – August period.

The Yellow River Basin has experienced significant surpluses in the most recent period, these will work their way through the system in the form of increased flows through the June – August timeframe.

Western China is expected to see continued mixed conditions with water surpluses continuing but moderating across western Tibet. To the north, however, severe to exceptional deficits are forecast to develop over a broad region stretching from western Inner Mongolia, across northern Gansu, and through central Xianjiang. These deficits are expected to intensify into December and the early part of 2018.

The later part of the forecast period (bottom right frame) indicates the development of moderate deficit conditions across the whole of Mongolia, northeastern China, the eastern plains, and the southern provinces of Guizhou and Guangxi.

(It should be noted that forecast skill declines with longer lead times.)