Facing their most significant drought in living memory, China is turning to cloud-seeding to bring rain to the parched reservoirs along the Yangtze River – the longest river in Asia that provides water for hundreds of millions of people.
It’s been a summer of record-breaking heatwaves in the US and parts of Europe – and it’s no different in China.
The National Metrological Centre put out a “red alert” weather warning last week with temperatures in a handful of regions expected to top 40°C (104°F), the state-run newspaper China Daily reports. Temperatures in China have remained high for over 63 days and they’re not expected to drop anytime soon.
With these baking temperatures comes drought. Rainfall is reportedly down 45 percent from average in China and water in the main body of the Yangtze – as well as two major lakes in its basin, Dongting and Poyang – has fallen to its lowest recorded level.
Local authorities have been advised to spray fields with a "water-retaining agent" to prevent water from evaporating or seeping away. Meanwhile, factories in some parts of the country were forced to shut down last week due to a surging demand for air conditioning and shortages of water to generate hydropower.
Many provinces are also looking to battle the drought with help of cloud-seeding operations, according to China Daily. Some provinces have opted for the use of cloud-seeding airplanes, while others have used ground-to-air cloud-seeding missiles.
Cloud seeding techniques can vary, but the process generally involves “seeding” the skies with silver iodide or other crystalline particles that have a structure similar to ice in clouds. Water droplets gather around the ice crystal in the atmosphere, like seeds for rain droplets, thereby increasing the chance of precipitation.
It's far from the only time China has dabbled with weather modification such as this. Last year, it was shown that Beijing used cloud seeding technology to ensure the celebrations of the Chinese Communist centenary would be blessed with blue skies and sun. They pulled off a similar feat to make sure the 2008 Summer Olympics were not hampered by rain.
Not all scientists are convinced that cloud seeding is an effective means of simulating rain. Some studies have found that cloud-seeding had little-to-no impact on the amount of rainfall in a given season, while others have found it may have some significant impact on precipitation.
Nevertheless, the need to address the drought is clear. The coming weeks are a key period for the autumn harvest of rice, grain, and other crops in the Yangtze basin. As reported by Reuters, high temperatures and desperate dry soils have impacted 457,500 hectares (1,130,507 acres) of land and already cost China $400 million in economic damage.
If left to persist, this drought could have a knock-on effect felt throughout the global economy.