Our project goal is to develop software to access HDF5 data via OPeNDAP software framework. OPeNDAP is a software framework that simplifies scientific data transfer, allowing simple access to remote data. Local HDF5 data can be made accessible to remote locations by using this OPeNDAP HDF5 server. Existing data analysis and visualization applications can be transformed into OPeNDAP clients that access remote HDF5 data served by OPeNDAP HDF5 server.
We have implemented an HDF5 data handler so that general HDF5 data can be served via OPeNDAP. In particular, we added the support of using the existing OPeNDAP clients to visualize NASA HDF-EOS5 Grid data. We believe that the server can help researchers, scientists, educators, and the general public visualize and analyze HDF-EOS5 data via existing DAP clients. The source code of the handler has been released by OPeNDAP. NASA GES DISC uses our handler to provide the Aura OMI Level-3 data.
The image below, generated by the GrADS client and later annotated (in orange) to highlight relevant elevations, shows the vertical profile of carbon monoxide(CO) over Beijing for three different dates in the summer of 2008. The amount of CO, reported in units of 1.0e-7 VMR (volume mixing ratio), is shown on the X axis. Atmospheric pressure, in hectoPascals (hPa), is shown on the Y axis. The CO amounts between 200 hPa (lower stratosphere) and 315 hPa (upper troposphere) are measures of pollution. These pressures correspond to elevations of approximately 12 and 9 kilometers above sea level. The plot clearly shows the CO levels measured by the Aura MLS instrument declined over the period examined, indicating improved air quality. The Aura MLS data served by NASA, the standard GrADS OPeNDAP client, and the HDF5-OPeNDAP data handler and prototype HDF5-friendly OPeNDAP client library facilitated quick analysis of Beijing air quality without relying on special-purpose tools or applications.
For more information, click the links on the left.
- - Last modified:September 23rd 2009