Principal Investigator (PI): Philip Callahan, NASA's Jet Propulsion Laboratory

We propose to implement an Altimeter Service (AS) using web-based tools to allow frequent and easy updating and customization of altimeter data products such as the Topography Experiment (TOPEX) GDR with retracking (RGDR). Under our OSTST proposal for TOPEX retracking, we will make a stand-alone version of this Retracked GDR (RGDR) with new precision orbits and Jason-1 geophysical models.

However, it is likely that many investigators will have other new orbits and improved geophysical models that could enhance the product or be useful for some specialized research purposes. In order to spare other investigators the difficulty of producing an entire GDR product, we propose to develop web-based tools to allow the creation of links between parts of the RGDR and additional new fields.

The links will allow users to dynamically create a residual sea surface height with various orbits, tides, and other geophysical fields produced by cooperating investigators to replace the values provided on the RGDR. This will allow for simple updating or testing and validation of alternative models by many users. To facilitate regional GDR processing and analysis, every dataset will be space/time subsettable and plottable, including the input base GDR, all available component models, and all reprocessed (updated) GDR versions.

The proposed development will support Climate Variability and Change science by enhancing studies of global sea level rise and ocean currents. It will also allow local oceanographic studies.