Radar data processing and visualization over complex terrain

MountainZebra is a data flow configuration that processes and displays rada r data over complex terrain. The system combines three elements: the data s tream from an operational radar, 3D topographical information, and the NCAR Zebra data visualization and integration software. MountainZebra operates routinely on a 3D data stream from the National Weather Service Weather Sur veillance Radar-1988 Doppler (WSR-88D) at Camano Island, Washington (near S eattle). The WSR-88D data are continuously acquired, archived, formatted, a nd interpolated for multidimensional display. The three-dimensional topogra phical information in MountainZebra can be automatically underlaid on any h orizontal or vertical display of the radar data. This system allows radar d ata and other geophysical fields to be analyzed in precise relation to the underlying terrain. Terrain-based visualization facilitates radar data analysis by identifying terrain clutter and shadowing and by identifying orographic precipitation m echanisms. The utility of MountainZebra is illustrated in the investigation of stable orographic enhancement over the windward slopes of the Cascade M ountains of the Pacific Northwest and an orographically enhanced squall lin e to the lee of the European Alps.