Advanced Semantic Concepts and Services in the Virtual Solar-Terrestrial Observatory

After almost three years experience in developing the Virtual Solar-Terrestrial Observatory (VSTO), we report on what we have learned about the level of knowledge representation required to satifying the science user needs. To date, we have achieved a unified query workflow based on an abstraction of classes (instrument, parameter, date-time) and provided semantic web services to make these available across the internet. We have also moved to the next level and generation of classes that capture science-level (higher) concepts such as state of the atmosphere, domains (e.g. neutral upper atmosphere), spatial locations, and parameterized representations of time (e.g. high geomagnetic activity). We also outline our plans for further representation, logic and reasoning within VSTO. VSTO is an NSF/OCI-funded joint effort between the High Altitude Observatory and the Computing and Information System Lab at the National Center for Atmospheric Research (NCAR) and McGuinness Associates Consulting.