"We've worked with neighbouring provinces on a contingency plan for rainstorm and other weather risks during the ceremonies," said Wang Yubin, a senior engineer at the Beijing Meteorological Bureau.

The Chinese government has spent £250,000 developing Beijing's cloud seeding programme over the last five years.

"At present, Beijing has relatively advanced technology for artificially influencing weather conditions," said Zhang Qiang, deputy director of the Weather Manipulation Office.

"That is to say, small or moderate rain can be eliminated artificially."

More than 100 staff at 21 stations surrounding Beijing will fire rockets containing silver iodide at approaching clouds, with the intention of causing rainfall before they can reach the stadium.

Three aircraft will also be available to spray a catalyst onto the clouds -- either silver iodide or liquid nitrogen.

"There are many very important factors in the implementation of the two methods," said Wang.

Officials have been keen to reassure citizens that the chemicals used in cloud seeding do not pose an environmental threat.

"Liquid nitrogen does not pollute the environment at all and we use just one gram of silver iodide per square kilometre," Wang said.

"We monitored the main water system from 2003 to 2007 and found no situations that failed to meet the environmental quality standards."

In spite of the scientific approach, some involved in the project still turn to older sources of reassurance in the hope of having good weather.

"I hope God will not send any storms to Beijing," said Zhang.