CHINESE emperors were once thought by their subjects able to make it rain with their prayers. Chinese officials today put more trust in science. They are boosting spending on what they call the world\'s largest programme of artificial rainmaking. Its effects, however, are not much easier to quantify.
中国古代的臣民曾以为他们的皇帝能够通过祈祷让老天下雨，而当今的中国官员则更相信科学，对其号称是全球最大人工降雨项目的投入也迅速加大。然而，到底能产生怎样的效果却较难量化。
（1）Just as grateful subjects praised the heavens for any rain that fell, the state-controlled media in China often report on the heroic contributions made by "weather-modification offices" whenever needed rain comes. These offices, set up over the past 15 years, deploy artillery, rocket-launchers and aeroplanes to seed clouds with chemicals （usually silver iodide） that encourage droplets to form and fall where needed, or prevent the formation of destructive hailstones.
正如心存感激的古代臣民为每一滴雨露歌颂上苍一样，中国国有传媒每当雨"有求必降"之时都会报道"人工影响天气办公室"所作的伟大贡献。在过去的十五年中，这类办公室相继成立，它们调动大炮、火箭发射器和飞机，利用化学品（通常是碘化银）来"播云"，作用要么是促进雨滴形成后降到需要雨水的地方，要么是防止破坏性冰雹形成。
China\'s efforts have been encouraged by an increasingly desperate shortage of water in the north. China also frets about the Olympic games in Beijing in August 2008, in a season when rainstorms are common. Making it rain away from big events is a key area of research. （2）Last week officials awarded merit certificates to organisations involved in "weather guarantee" work for a summit with African leaders held in Beijing in November. Those honoured included the air force, Beijing\'s military command and the Second Artillery, which controls missiles. All were urged to do a good job at an Olympic rehearsal next year.
中国之所以这么做，是因为北方缺水问题日益严重。中国还为2008年8月北京奥运会感到担忧，届时北京将正处于暴风雨季。让降雨避开大型活动是研究的一个关键领域。上周，官员向为11月北京非洲领导人峰会提供"天气保障"服务的有关单位颁发了奖状，受奖单位包括空军、北京军区和二炮（控制导弹的部队）。官员还敦促所有单位在明年奥运会预演时能有出色表现。
Artificial rainmaking is practised in many countries but its success is hard to prove. In recent years, China has been helped by big improvements in its weather-monitoring capacity. Its latest satellite, Fengyun-2D, was launched on December 8th with Olympic forecasting as a priority mission. It plans to launch another 22 weather satellites by 2020.
许多国家都开展了人工降雨，但难以证实其成功作用。近年来，中国在天气监控能力上有了很大提高，从中也受益颇多。12月8日发射的风云－2D是中国最新发射的一颗卫星，其首要任务是为奥运会提供天气预报服务。中国计划在2020年以前再发射22颗气象卫星。
Mao Jietai of Peking University says circumstantial evidence suggests cloud seeding can increase precipitation by around 10%, but admits doubts about its real efficacy. （3）Undaunted, the government has set an annual target for artificially induced rain nationwide for the next five years: around 50 billion cubic metres, or five times parched Beijing\'s average. As in imperial times, few will be able to refute claims of success.
北京大学的毛节泰（音）称，有间接证据表明，"播云"可能提高大约10％的降雨量，但他也不否认对其实际功效表示怀疑。政府并没有因此泄气，它已经为今后五年全国范围内的人工降雨制定了一个年度目标，即每年人工降雨大约500亿立方米或者达到北京低降雨量的5倍。就像帝王时代一样，上面说会成功就一定会成功，谁敢说不？ |
