The Effects of Orientation of Hydrometeors on the Estimation of Differential Propagation Phase

Data from the S band Doppler and polarimetric weather radar at McGill University are presented. Radials crossing the melting layer are considered. Negative gradients of the differential propagation phase at the rain to melting layer interface and equivalent positive gradients at the melting layer to snow interface are isolated. It will be shown that these features are not a consequence of bacskscattering phase shift but of the assumption of equioriented hydrometeors commonly made for the estimation of differential propagation phase.