Taking two small, spherical particles for example, the backscattering cross-section as a whole during the stage of edge conglutination between them would be greatest as compared with that before they contact with each other and that after they fuse and coalesce into a single spherical particle, especially the conglutination and coalescence process starts from two small, spherical ice particles. The paper studies the contribution of this phenomenon to radar bright band. DDA is used to calculate DDA, the backscattering cross-section of the edge-conglutinated particles. It has been found that DDA in case the conglutination is along the direction of radar wave polarization may be 1.5 times greater than mie, the backscattering cross-section of the equal volume, spherical particle at a certain size though the ratio may decrease to even less than 1 and fluctuate as the particle size increases because of resonance for large particles. Introducing'probability of edge conglutination'as a parameter to depict the effect of edge conglutination and applying the parameter into simulating radar bright band, it has been shown that, for a normal intense cloud echo such as 5874 mm6·m-3 (37.69 dBZ), radar reflectivity factor can increase by 2.57 times in case the conglutination percentage=33%, increase by 3.29 times in case p=50%, and increase by 5.59 times in case p=100%, respectively, while the increase is only increase by 2.40 times if the conglutination is not considered. Therefore, conglutination on the edge of two spherical particles along radar wave polarization direction can effectively increase the radar reflectivity factor and greatly benefit the formation of bright band.
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