Every cloud has a silver lining?

HONG KONG, China (CNN) -- One of the best times to visit China's capital, some tourist guidebooks say, is in August, despite temperatures that can soar as high as 40 degrees Centigrade -- and despite the rain.

August is not only one of the hottest months of the year in Beijing, it's also one of the wettest. The only time of the year that is hotter or wetter than August is July.

The 2008 Beijing Olympic Games were originally scheduled to start in July. But in 2003, Beijing persuaded the International Olympic Committee (IOC) to move the dates back a couple of weeks, following concerns for the well being of the Olympic athletes in the heat and humidity.

For a country that associates the number "8" with prosperity and good fortune, the date they settled on was particularly auspicious: the eighth day of the eighth month of 2008.

Then in 2006, Beijing experienced an unusually wet August. The Beijing Organizing Committee (BOCOG), keen to allay fears that rain could be a key player in the Olympics, moved quickly to reassure the public. All signs point to a dry opening ceremony, they said.

"The possibility of rain on August 8, 2008, is between 30 and 40 percent," Jiang Xiaoyu, BOCOG executive vice-president said at the time. "If it does rain, it will most likely be only a drizzle."

Jiang's conclusion was based on an analysis of rainfall trends for August during the past 50 years. It found that in the past 10 years, no rain had fallen in Beijing on August 8.

But if that wasn't enough come next August, Beijing had something else up its sleeve. The Beijing Weather Modification Office, along with thousands of Chinese peasants, plan on firing rockets containing silver iodide into the sky to disperse rain clouds before they even reach the Olympic Stadium.

It's a technique known as cloud seeding that has been tried before in many countries as far back as the early 20th century, with varying degrees of success. Most recently, Russia claimed to stave off ruinous rain for St. Petersburg's 300th anniversary in 2003.

Today, China's weather modification operations are supposed to be the largest in the world, according to Xinhua, involving operations in 30 of the countries provinces, municipalities, and special administrative regions.

The China Meteorological Association claims to have created 250 billion tonnes of rain since 1999 and has equipped itself with 7,113 anti-aircraft guns, 4,991 special rocket launchers and more than 32,300 dedicated personnel. It expects the volume of annual artificial rain it generates to reach 50 billion tonnes by 2010.

Beijing has also taken its weather control mission into space. The idea: to provide the most accurate and up-to-date forecasting possible.

In December 2006, it launched its second geostationary orbit meteorological satellite, Fengyun-2D, into space to work in tandem with China's first geostationary orbit weather satellite -- launched in October 2004.

Both satellites will provide weather updates every half-hour and comprehensive monitoring of disaster weather, according to People Daily.

But that's not all. The Chinese Academy of Meteorological Sciences has developed a thunder and lightning monitoring and warning system, now in its experimental stages, which can predict storm activity up to an hour before it occurs.

But need there be so much fuss? In modern times, the Summer Olympics have enjoyed a surprisingly good run since their inception in Athens more than 111 years ago. While bad weather forced the cancellation of the rowing and sailing events at the 1896 Games, since then weather disruptions have been few and far between.

According to the International Society of Olympic Historians, there have only been a handful of occasions where the weather has had an important role to play at the Games.

In the 1912 Stockholm Games, extreme heat claimed the life of Portuguese marathon runner Francisco Lazaro. He died in hospital the day after collapsing from heat exhaustion 30 kilometers into his race. Heat was again a culprit at the 2004 Athens Games, when British marathon runner and gold-medal favorite Paula Radcliffe abandoned her race after 37 km.

While it is questionable if rain has ever caused an Olympic event to be called off, it did play havoc at the 1948 London Olympics, when Belgian Gaston Reiff beat Czechoslovakian Emil Zatopec by two-tenths of a second on a puddle-ridden cinder track that left the runners black from splattered mud.

In 1976, Montreal's heavy downpours -- which momentarily extinguished the Olympic flame -- led to a sodden track for the equestrian events, resulting in every competitor registering rare multiple faults.

For all China's investment in weather control, some climate scientists are still unsure to what degree it actually works. "It's still a scientific application in its early days. There's still a lot to learn," says Dr Deon Terblanche, a World Meteorological Organization weather modification expert.

In the meantime, it offers the only hope of controlling what is otherwise thought of as the uncontrollable. "The energies in the atmosphere are so large that there really are no other means of doing it," Terblanche said. E-mail to a friend

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