Abstract:According to observations of field test and numerical simulations, the basic characteristics of the design of the test area for the effect test of surface precipitation enhancement operation are analyzed by using the ideal conceptual model of artificial precipitation enhancement. The influence of operation sequence, moving speed of cloud system, and coverage rate of catalytic cloud system on the rainfall points in the test area on the effect evaluation is investigated. The results are shown as follows. 1) The moving speed of cloud system should be regarded as an important indicator of selecting target cloud, which directly affects the length of the test area and the layout of operation points, and also has a great impact on the effect evaluation. The target cloud system with different moving speed distributes the artificial precipitation to different areas, which increases the difficulty of the effect evaluation. 2) There exists the rainfall data of the shortest time span, which is jointly determined by the length of the test area, operation time, and moving speed of the target cloud, and it can be used to evaluate the effect. 3) The calculation formulas of the ratio of operation time to rainfall time used for statistics of effect, and the relative precipitation enhancement rate by the influence of catalytic cloud system on the coverage rate of the rainfall points in the test area are given, respectively. Based on these formulas, the randomized experiment data of Israel I are quantitatively analyzed. The results show that to evaluate a certain relative precipitation enhancement rate, it is necessary to artificially catalyze the cloud system to have a greater precipitation enhancement, that is, to change the natural precipitation significantly.