Study of mixed phase clouds over west Africa: Ice-crystal corner reflection effects observed with a two-wavelength polarization lidar

Lidarsounding is used for the analysis of possible contribution of the corner reflection (CR) effect to the total backscatteringin case of ice crystals. Our study is based on observations of mixed phase clouds performed during the SHADOW campaign in Senegal. Mie-Raman lidarallows measurements at 355 nm and 532 nm at 43 dg. off- zenithangle, so the extinction and backscattering Angstrom exponentscan be evaluated. In some measurements we observed the positive values of backscattering Angstrom exponent, which can be attributed to the corner reflection by horizontally oriented ice plates.