A Graphical User Interface for Cloud Radar Spectra Data Discovery

The Department of Energy's Atmospheric Radiation Measurement Program collects long-term cloud observations with vertically-pointing and scanning cloud radars at a number of climatically important sites around the globe. Approximately 20 cloud radars are typically operating at four fixed and two mobile sites. These radars collect Doppler radar spectra continuously while at vertical incidence. The spectra are a potentially rich source of high-resolution microphysical information; however, finding phenomena of interest can be a daunting task due to the sheer volume of data available. Typical data volumes are on the order of 15 GB per day, per radar. A prototype graphical user interface was developed to assist in data discovery. The application, called 'SpectraView,' allows the user to visually scan through data, starting with daily reflectivity images and ‘drilling down' to Doppler spectra representing each time-height radar volume, and follow the evolution of spectral features of interest in time and height. The original application was developed in the proprietary IDL language. As a consequence, application users without purchased IDL licenses must install an IDL virtual machine in order to run it. Also, although the application has potential applicability to spectra data collected by any radar, the possibility for ongoing community development of the software is limited to users with IDL licenses. To address these and other issues, the prototype application has recently been ported from IDL to Python, using the WxPython toolkit. We will discuss our motivations, describe our conversion experience and show the IDL vs. Python user interfaces.