January 30, 2008

Beijing Bureau Prevents Rainfall

Zhang Qian, head of weather manipulation at the Beijing Meteorological Bureau may have found a way to keep the opening ceremony at August's Olympic Games dry. The attempts to mitigate light rain have been successful thus far.

The Bird's Nest Stadium, where the Olympics will be held, has no roof. Because of this, the bureau has been instructed to prevent wet weather on August 8th.  Thus far, Zhang Qian and the bureau have been able to prevent light rain, but she says that it is much more complicated to stop heavier rain.

Although, as Qian says, "Rain mitigation is a very complex process," China has been using weather manipulation techniques for a very long time. Typically these tools are used to increase rainfall, as opposed to stopping it. Rainfall can be changed by firing anti-aircraft guns loaded with seeding agents into the clouds.

One method they have tried is to induce the rain to fall, using their normal rain-induction technologies, prior to its reaching the Bird's Nest.

Other strategies, which Qian says will not harm the environment, include a variety of seeding agents.

For clouds below zero degrees Celsius, she says that a coolant made from liquid nitrogen will increase the number of droplets while decreasing their size. The smaller the droplets, the less likely they are to fall.

If clouds are above zero degrees, silver iodide will accelerate the "droplets' collision and coalescence". This will hinder the formation of clouds because of the strong downdraft produced.

The bureau is also preparing for the pre-game ascent of the Olympic torch to the summit of Mount Everest.