Artificial weather

Artificial rain -or in this case snow- is usually mentioned as a way to improve agriculture production, or mitigate the randomness of weather. China as usual moves ahead, but the results are questioned.

Chinese Debate Creation Of Artificial Snow Over Beijing
Wednesday, 11 November 2009
Scientists in China refueled the debate over the practice of tinkering with Mother Nature by artificially inducing the second major snowstorm to wreak havoc in Beijing this season, AFP reported.

The National Meteorological Center said the earliest snow to hit the capital in 22 years fell on the first of November and the capital was again shrouded in white Tuesday with more snow expected in the coming three days.

The Beijing Weather Modification Office had artificially induced both storms by seeding clouds with chemicals, a practice that can increase precipitation by up to 20 percent, according to The China Daily, which cited an unnamed official.

On Tuesday, an official had said the storm was "natural."

Such methods are aimed at alleviating a drought over much of north China -- including Beijing -- that has lingered for more than a decade, city weather officials reported.

Meanwhile, many residents of Beijing have complained about the flight delays, traffic snarls, cancelled classes and other inconveniences of a surprise snowstorm.

Most agree that officials could warn them if they are planning to toy with the clouds.

The paper reported that beyond the day-to-day hassles, experts said the weather manipulation had other undesirable side effects in the longer term.

Xiao Gang, a professor in the Institute of Atmospheric Physics at the Chinese Academy of Sciences, told the paper that no one could tell how much weather manipulation will change the sky.

"We should not depend too much on artificial measures to get rain or snow, because there are too many uncertainties up in the sky," he said.

The more than 5,500 tons of erosive snow-melting chloride used on city roads Tuesday -- nearly half the annual allotment -- could erode steel structures of buildings, according to Zhao Nan, a Beijing engineer, was quoted in The China Daily.

The paper cited official statistics that showed the snow-melting agent was responsible for killing 10,000 trees in Beijing and decimating 2.15 million square feet of grassland in 2005.

State press reports said that despite a massive effort to clear the capital of snow that involved over 15,000 workers, many roads remained blocked, while highways into Beijing and in neighboring Hebei and Shanxi provinces were shut down.