Relation of rain rates at the ground and aloft—a model study

Z-R relations empirically relating the reflectivity factor Z at a certain height above the radar to the estimated rain rate at the ground are often applied in radar meteorology. While there are uncertainties involved with the Z-R relation alone, also the vertical profile of rain rate R has to be taken into account. Especially in weather situations with deep convection, application of Z-R relations can easily lead to large errors in determining areal precipitation accumulation.

The poster describes an evaluation of cloud-resolving model studies (using two different mesoscale models) for a small and a large thuderstorm cell, respectively. Applicability of Z-R relations will be investigated and a method to optimize radar-derived precipitation accumulation in convective situations will be outlined.