Several regions on the Yangtze have launched weather modification programs, but with too thin cloud cover, operations have remained on standby in some drought-ravaged parts of the river basin.
The Ministry of Water Resources said in a statement on Wednesday that the drought in the Yangtze River Basin “had adversely affected the drinking water security of rural populations and livestock, and crop growth.”
On Wednesday, central China’s Hubei province was the last to announce it would seed clouds, using silver iodide rods to induce rainfall.
The silver iodide rods — which are typically the size of cigarettes — are shot into existing clouds to help form ice crystals. The crystals then help the cloud produce more rain, making the moisture content heavier and more likely to be released.
Cloud seeding has been used since the 1940s and China has the largest program in the world. It used seeding prior to the 2008 Beijing Olympics to ensure dry weather for the event, and the technique can also be used to induce snowfall or mitigate hail.
At least 4.2 million people in Hubei have been hit by a severe drought since June, Hubei provincial emergency management department said Tuesday. More than 150,000 people have difficult access to drinking water and nearly 400,000 hectares of crops have been damaged by high temperatures and drought.
Communities often depend on these bodies of water for economic activity, and governments have to intervene with adaptation measures and emergency funds, at a huge cost.
China is deploying such funds and developing new sources of supply to deal with the impact on crops and livestock. Some of the livestock has been temporarily relocated to other regions, the Treasury Department said earlier this week, adding it would spend 300 million yuan ($44.30 million) on disaster relief.
To boost downstream supply, the Three Gorges Dam, China’s largest hydropower project, will also increase water discharge by 500 million cubic meters over the next 10 days, the Ministry of Water Resources said Tuesday.
‘Longest’ and ‘strongest’ heat wave ever
China issued the highest red alert warning on Wednesday for at least 138 cities and counties across the country, and a further 373 were placed under the second-highest orange warning, the Meteorological Administration said.
On Monday, China’s heat wave had lasted 64 days, making it the longest in more than six decades since full recording began in 1961, the National Climate Center said in a statement. It also said it was the “strongest” ever and warned it could worsen in the coming days.
“The heat wave this time is prolonged, broad in scope and strong in extremity,” the statement read. “Taking all the signs together, the heat wave in China will continue and its intensity will increase.”
The heat wave has also registered the largest number of counties and cities to exceed 40 degrees Celsius (104 degrees Fahrenheit) since records began, according to the statement. The number of weather stations recording temperatures of 40C and above has reached 262, also the highest. Eight have hit 44C.
High temperatures are forecast to persist in the Sichuan Basin and large parts of central China through August 26.
A “special case” of high pressure from the subtropical plateau in the western Pacific, which spans much of Asia, is likely the cause of the extreme heat, said Cai Wenju, a climate researcher at CSIRO, the national scientific research institute of CSIRO. Australia.
DailyExpertNews’s Larry Register, Angela Dewan and Laura He contributed to this report.