SA54A-01 INVITED 16:00h
Data and Metadata Standards: Lessons Learned From the Madrigal/Cedar Databases
The Madrigal/Cedar databases have served the atmospheric science communities since the 1980's as early examples of virtual observatories. The keystones of these databases are the Cedar database standard and the Madrigal metadata standard. The Cedar database standard defines several thousand parameters that can be measured, and was developed as a community-wide effort in the 1980's. The Madrigal metadata standard was developed to allow the many separate Madrigal database installations to share high-level information about what data they store, allowing a user to access any individual Madrigal database as if it contained all the data in all the Madrigal databases. This talk will focus on the lessons learned from these data and metadata standards. Even these simple standards have allowed the Madrigal database to contain a powerful engine that allows it to derive many parameters beyond those measured, allowing complex searches across the entire database. The various ways these standards could be improved will also be discussed. A fundamental lesson is that the up-front development of data and metadata standards make virtual observatories both far easier to develop, and far more functional.
SA54A-02 INVITED 16:15h
An analysis of ionospheric data availability and quality
Over the last many years, we have used a great deal of data to run data assimilation and 3D numerical models of the ionospheric electrodynamics, magnetospheric dynamics, and thermospheric dynamics. In order to create the best possible data assimilation inversions, and validate the models as well as possible, many different data types from many different sources need to be utilized. In this talk, we will describe the availability of such data and their general quality. We show how a large amount of ground-based magnetometer data have serious quality issues such as spikes, base-line shifts, saturation effects, and general noisiness. In addition, we will suggest possible ways in which the data quality and availability can be improved.
SA54A-03 16:30h
The Importance of Data Quality on Studies of Short-term and Long-Term Ionospheric Processes
The 50-year record of ionospheric observations from ground-based stations worldwide provides a valuable data set for several applications, including studies of short-term processes and detection of long-term environmental change. The ionospheric region is subject to large natural variability as a result of numerous influences including solar and geomagnetic activity. These variations occur on both short and long timescales and must be well understood before a clear trend or signal can be identified. Previous analyses of the layer heights and critical frequencies have provided conflicting results, and an evaluation of various approaches suggests that data quality has a significant influence on studies of both short- and long-term ionospheric behavior. Exploring the quality of the observations brought to light three main areas that must be addressed before the data are suitable for analysis. First, changes in instrumentation, including the switch from analog to digital technology, have resulted in observable shifts in the data records. Understanding and accounting for these shifts can reduce biases that may result when analyzing the time series of observations. Second, many of the records contained time periods during which no data were reported. These gaps, if not properly addressed in the data analysis, can affect the evaluation of both trends and forcing mechanisms. Third, changes in how parameters (particularly peak layer heights and virtual heights) are inferred can also affect the analysis. These problems have been carefully addressed for four ionosonde stations and have resulted in a corrected, more robust data set for analyzing storms and other short-term processes and for assessing long-term trends. We will summarize some of the issues affecting the data record and will present preliminary results from analyses of the improved data set.
SA54A-04 16:45h
The Space Physics Archive Search and Extract (SPASE) System for Space Physics Data
The Space Physics Archive Search and Extract (SPASE) system is a collaborative development effort among multi-institution, international, space physics data holding organizations intended to provide a common ground for science users to find space physics data of interest, intercompare the data, and retrieve selected data sets or portions of data sets. SPASE has developed a data model that serves as a bridge among the many space physics data archives that have data stored in multiple formats and offer access via multiple search methodologies. Our goal is to create a framework that will allow searches to be done across multiple data centers through a single mechanism. Development of an intermediate level of software will translate queries into the search mechanisms specific to each of the data centers. The results of the search are then to be put into a common format for presentation of the search results. Metadata entry tools are planned to ease the translation of the metadata to be found at the archive locations to the common metadata format needed for SPASE searching. Recent meetings among the data archive representatives and the progress of the space physics virtual observatories toward a unified space physics data environment will be discussed.
http://www.igpp.ucla.edu/spase/
SA54A-05 17:00h
The TIMED Science Data System: Experiences in Operating a Distributed Data System
The Thermosphere Ionosphere Mesosphere Energetics and Dynamics (TIMED) Science Data System (SDS) operates, after more than two years since launch, as the distributed system for the acquisition, archive and distribution of science data in support of TIMED investigators and the ITM scientific community. The SDS maintains a single integrated user interface, implemented as a World Wide Web (Web) site, by which users locate, understand and use its collection of data. The SDS unites resources distributed across a number of different facilities: a Mission Data Center (MDC), four remote instrument Payload Operations Centers (POC), and collaborating GBI sites and CEDAR. Presented are the experiences and lessons learned, from the perspective of the centralized components of the MDC and SDS, in providing data and services to the community and plans for meeting users' needs in the evolving data environment.
http://www.timed.jhuapl.edu/
SA54A-06 17:15h
ITM-Related Data and Model Services at the Sun Earth Connection Active Archive (SECAA)
NASA's Sun Earth Connection Active Archive (SECAA) provides access to a large volume of data and models that are of relevance to Ionospheric, Thermospheric and Mesospheric (ITM) physics. SECAA has developed a number of web systems to facilitate user access to this important data source and is making these services available through Web Services (or Application Programming Interfaces, API) directly to applications such as VxOs. The Coordinated Data Analysis web (CDAWeb) lets user plot data using a wide range of parameter display options including mapped images and movies. Capabilities also include parameter listings and data downloads in CDF and ASCII format. CDAWeb provides access to data from most of NASA's currently operating space science satellites and many of the earlier missions; of special ITM interest are DE-2, ISIS, FAST, Equator-S, and TIMED. SECAA maintains and supports the Common Data Format (CDF) including software to read and write CDF files. Most recently translator services have been added for CDF translations to/from netCDF, FITS, CDFXML, and ASCII. The SSCWeb interface enables users to plot orbits for the majority of space physics satellites (including TIMED, UARS, DMSP, NOAA, LANL etc.) and to query for magnetic field line conjunctions between multiple spacecraft and ground stations and for magnetic region occupancy. Recently an Interactive 3-D orbit viewer was added to SSCWeb. Access to legacy data from older ITM satellite missions is provided through the ATMOWeb system with the ability to generate plots and download data subsets in ASCII format. Recently added capabilities include the option to filter the data using an upper and lower boundary for any one of the data set parameters. We will also present the newest version of the web portal to SECAA's models catalog, ftp archive, and web interfaces. The web interfaces (Fortran, C, Java) let users compute, list, plot, and download model parameters for selected models (IRI, IGRF, MSIS/CIRA, AE/AP-8). All systems can be accessed through the SECAA homepage at http://spdf.gsfc.nasa.gov/
http://spdf.gsfc.nasa.gov/
SA54A-07 17:30h
The Virtual Solar-Terrestrial Observatory
The VSTO is being developed as a scalable environment for searching, integrating, and analyzing databases distributed over the Internet. The VSTO comprises a system of data, model, tool and material archives containing items from space- and ground-based instruments, individual and community modeling efforts, taken from NCAR, US universities and international sources, and from NSF- and NASA-funded groups. A key element of the VSTO is the allowance for an integrated data-mining and analysis capability that can be applied both across and within databases, i.e. across disciplines. The capabilities of a VSTO are intended to be available to a wider community of scientists, educators, and the public and thus is intended to be a natural conduit for education and public outreach in solar solar-terrestrial and space physics. This presentation will outline the key user requirements, functionality, proposed architecture and technologies that will be used in assembling the VSTO. We will also present past experience in building elements of data and collaborations system and the lessons learned.
SA54A-08 17:45h
A Virtual Observatory for the Ionosphere, Thermosphere, and Mesosphere community
The ionosphere, thermosphere, and mesosphere (ITM) community studies an area of the atmosphere that is a transition region between the atmosphere and space, where many important physical and chemical processes change dramatically temporally and spatially. As a result, the areas of studies within the ITM community span a wide spectrum of scientific subjects in geophysics and space physics. The relevant data for the community collected during the past few decades consequently come from a variety of sources including ground and space-based instruments as well as from modeling and data assimilation. As the different sub-fields mature, a system-oriented approach to understand the ITM as a whole and its relationship to the sun and the surrounding geospace environment is critical. This approach requires a data system with efficient access to all data sets (present and historical) relevant to disciplines across agencies, including NASA, NSF, NOAA and others. A preliminary Virtual ITM Observatory (VIO) concept for such a data system is presented as a grassroots level effort by the community that leverages current resources. The design incorporates a modular framework that accepts distributed data and services from across the community and encourages widespread participation. Data can be added as both new missions and historical holdings become available, and services added or replaced as technologies and standards evolve. The core VIO system is based upon a set of services: centralized browse and query/retrieval of distributed resources, access to data reader software and other tools, and integration of current data with data from previous missions and long-term data sets. The VIO concept is presented to the community for discussion and community-wide input as part of a definition phase.