¹UNAVCO/UCAR POB 3000, Boulder, CO 80307-3000, United States
²IGPP Univ California San Diego, La Jolla, CA 92093-0225, United States
³NASA Goddard SFC MC920 1, Greenbelt, MD 20771, United States
⁴Stanford Univ Dept Geophysics Mitchell Bldg, Stanford, CA 94305-2215, United States

There are many GPS data archives operated by groups throughout the U.S. and worldwide. Each of these GPS archives typically has an interest in just a few particular types of data - for instance: data from the southern California area; or data from the world-wide IGS network; or data which was collected with funding from a particular agency. These archives have operated in a manner to best meet the needs of their constituents, but "outside" users have had to be fairly sophisticated to find information of interest.

A more cooperative (and coordinated) arrangement between these archives would provide all users with easier access to GPS data and metadata. It would be much easier for users if they could find and retrieve data simply by contacting one center, instead of contacting all of them separately. We call this concept of an interoperable multi-archive system the "GPS Seamless Archive Center" or GSAC. We have identified a minimal meta-data description and exchange mechanism with which we propose to establish such a system between cooperative archives. The GSAC will provide a product stating locations and times for which GPS data was collected, and where data is stored and how to get it.