Vast belts of forest planted across the northern arid lands of China, called ''The Great Green Wall,'' are probably one of the most aggressive weather modification programs in the twentieth century. The purpose is to reduce eolian transport of dust from the Gobi Desert. Preliminary data indicate a negative trend in dust-storm frequency and duration since the 1960s. Effects on atmospheric radiation and cloud microphysics appear to be statistically insignificant in the studied period. However, only time can show any long-term impact on our environment. ¿ American Geophysical Union 1994