Three-dimensional simple adjoint velocity retrievals from single-Doppler radar

In this paper, the original simple adjoint method of Qiu and Xu is improved and tested for retrieving the 3D storm-scale wind field from single-Doppler radar data. The method incorporates single-radar data and background fields, along with a dynamical constraint, smoothness, and anelastic mass continuity constraint, in a cost function. The minimization of the cost function, with the desired fit to these constraints, is obtained in an iterative procedure. The current method is tested on simulated datasets of supercell storms. It is shown that the circulation inside and around the storms, including the strong updraft and associated downdraft, are well retrieved. Furthermore, the method is robust in the presence of data error.