Saturday, August 02, 2008
And now the weather...for Beijing
So will they try to seed the thunderstorms before the opening ceremony? You bet they will. This from the Chinese news agency Xinhua last week
Cloud seeding, a technology developed by American scientists, is achieved by shooting shells or rockets containing silver iodide particles into clouds. The icy particles freeze drops in the clouds, make the drops continue growing and eventually fall out of the clouds. The weather engineering office is weaving a defensive web from adjacent provinces to the Beijing suburbs. Twenty-six control stations have been deployed to fend off clouds or delay their movement. The office hires 32,000 people, and recruits light aircraft, rockets and shells to spread silver iodide crystals or dry ice in clouds 50 km upwind of Beijing. Result estimates can be reported from control stations to the headquarters within 10 minutes. One silver iodide shell costs up to 88 yuan (12.75 U.S. dollars),one rocket is priced at 2,000 yuan (290 U.S. dollars), and one aircraft trip spends much more. About 100 shells or four rockets are used in each single action, according to experts. The office claimed to have eliminated a cloud by airborne spread of infusorial earth on its top on June 2, 2005, which was not found documented in an academic journal. Meteorologists need to capitalize on radars and weather satellites to monitor colossal storms, which are usually unpredictable, and set off early warnings for Olympic weather services.
Is man playing "rainmaker" a bad thing to be condemned? No. I'm just curious to see whether it will really work.
Remember, the United States started seeding clouds to make rain in the 1950s, but later gave up because they could not work out whether the seeding produced more rain than if they did nothing. There is no reference or control - you don't have two identical clouds, where you seed one and not the other to compare the result. Nevertheless, China now boasts it is the world's leading rainmaker.
It has created enough rain during the past five years to fill the Yellow River, the nation's second largest, four times over, Xinhua said back in 2006.
Between 2001 and 2005, nearly 3,000 flights triggered 210 billion cubic meters of water over an area making up nearly a third of China's territory, an official from the National Meteorological Bureau told Xinhua. An army of more than 3,000 rainmakers have at their disposal 7,000 cannons and 4,687 rocket launchers to coax more rain from clouds across China.
The chance of rain on August 8th looks much higher than the normal average, but there are still 6 days to go. The rain beforehand will bring welcome relief to the current scorching temperatures in the Chinese capital.