NASA's Radar Software Library (RSL) and RSL in IDL

In support of the Tropical Rainfall Measuring Mission's (TRMM) Global Validation Program, the NASA TRMM Satellite Validation Office has developed a Radar Software Library (RSL) for ingesting, analyzing and outputting several common radar data formats. RSL is an object oriented programming environment for writing software applicable to all RADAR data related to the TRMM GV effort. This library can ingest data in WSR-88D, Lassen, Sigmet, McGill, UF, HDF, RAPIC, RADTEC and native RSL file formats. Additional functions are provided to manipulate the RSL objects. For example the Radar object is the method used to define the ideal or universal radar representation, while maintaining the natural resolution of the data. More simply, Radar represents the superset of all radar file formats. The Radar structure is hierarchically defined such that it is composed of Volumes, each containing one field type. Volumes are composed of Sweeps. Sweeps are composed of Rays and Rays contains a vector of the field type. Some field types are Reflectivity (DZ), Velocity(VR), Spectrum Width(SW), etc. There are approximately 20 supported field types, including those that are common to newer dual-polarization radar. More recently, the C-based RSL library has been ported to IDL (RSL_IN_IDL), which provides a more scientist-friendly interface for ingesting, analyzing and visualizing radar data. We present these two libraries, which are currently released under the GNU public license as open source code. It is our hope that we can work with the radar community to make updates and improvements to this very popular set of libraries.