*************************** ** THE GEM MESSENGER ** *************************** Volume 6, Number 27 June 6, 1996 ------------------------------------------------------- NEW ACCESS (CDAWeb) TO ISTP'S PUBLIC KEY PARAMETER DATA ------------------------------------------------------- From: Mona Kessel (KESSEL at nssdca.gsfc.nasa.gov) New Access (CDAWeb) to ISTP's Public Key Parameter Data (R. L. Kessel, R. J. Burley, R. E. McGuire, M. Peredo) The NASA/GSFC Space Physics Data Facility (SPDF) and the National Space Science Data Center (NSSDC) have just released a new, World-Wide-Web-based system for accessing the public ISTP Key Parameter (KP) database : CDAWeb, the Coordinated Data Analysis (Workshop) Web. - The system is tied to a **complete and current** database of the full public ISTP KPs presently in production. - At this time there are about **400 data variables** from Geotail, Wind, Interball, ancilliary spacecraft and ground-based investigations. More variables will be added in the near future from Polar and SOHO. - CDAWeb supports interactive plotting of variables from multiple instruments on multiple investigations simultaneously on arbitrary, user-defined time-scales. It also supports digital data retrieval in both CDF or **ASCII** format. ISTP spacecraft Key Parameters supply particle and field measurements at approximately 1 minute resolution. Geotail KPs include low-energy electron and ion fluxes at 32 energies and 4 look directions; plasma density, pressure and bulk flow velocity; energetic particle differential and integral fluxes, abundance ratios, anisotropies; and magnetic and electric field components, spacecraft potential and bias current. Wind KPs include ion and electron density, velocity and temperature, ion (proton, He, CNO, Iron) and electron fluxes, electric field background, transients, and average values at 76 frequency values, and magnetic field components. Additional particle and field KPs are provided by ancilliary spacecraft such as IMP-8 and the LANL and GOES geosynchronous satellites. Ground-based investigations such as HF Radars, VLF/ELF/ULF Radars, Incoherent-Scatter Radars, Magnetometers, Riometers, Sounders, Photometers and an All Sky Imager, provide data at anywhere from 1 minute resolution to 30 minute resolution depending on the type of measurement. In many cases the data are more complicated than can be displayed in simple time series plots, and thus are displayed as e.g., spectrograms, images, or ionospheric convection patterns. The direct path to CDAWeb access to the full set of public ISTP Key Parameters is from http://cdaweb.gsfc.nasa.gov/cdaweb/istp_public/ We believe this is a powerful new capability to better leverage the combined KP database to accomplish the coordinated science objectives of ISTP. We invite you to take this opportunity to look for events in the key parameter data sets, possibly events that you have found already through analyzing other data. Resident with the data is the necessary information (metadata) on labels, time tags, dependencies, display types, etc. so that the steps needed to actually display the data are minimal. (note: The ISTP Key Parameters are preliminary data intended for use as BROWSE data. Users interested in publication-quality versions of this data are encouraged to contact the appropriate Principal Investigator(s).) To use CDAWeb: - choose a mission group (e.g., Wind, Geosynchronous spacecraft, ground-based investigations) and/or instrument type (e.g., Magnetic Fields (space,) Particles (space), Ground-Based HF-Radars), and - choose from a list of variables for each selected data set , specify the time range, and specify whether you want a plot or a listing/ASCII file. The data are then processed and returned (as plots or listings). The plots are in fact a set of GIF image(s) that can be easily downloaded for local save if desired. The listings can be displayed to the screen, saved directly as (an) ASCII file(s) (as an option of your local browser/use "source" mode), or you can download the CDF data files themselves. At this time, the type of plot used for a particular variable is pre-selected and cannot be changed. Other plot types and functionality will be added in future. (We note that the powerful underlying plot software is in IDL and we plan to make this software accessible in the fairly near future.) We would also like to point out that the Space Physics Data Facility home page at URL : http://nssdc.gsfc.nasa.gov/spdf/ has links for all of the currently supported CDAWeb databases as well as access to SPyCAT (NSSDC/SPDF's Space Physics Catalog web interface to the more comprehensive NDADS near-line archive), and access to other useful information and tools. One such tool (Gif_walk) aids access to a database of orbit plots created by the ISTP Science Planning & Operations Facility (SPOF) based from the SPDF/NSSDC Satellite Situation Center software and database. Gif_walk is also configured for access to the SPOF's database of existing standard summary plots of Key Parameters being used to check Key Parameter data quality and to identify events. Please note the platforms supporting these large databases are being upgraded now, but response may be somewhat slow until these upgrades are complete. This full ISTP public KP data access will be the largest-scale user exposure to the system to date, and the first wide exposure of the system combined with this database. Please report any anomalies or problems as they are seen in your testing and use. We hope you like what we've done. For questions or comments on CDAWeb, please contact either Mona Kessel (301-286-6595, kessel at nssdca.gsfc.nasa.gov) or Bob McGuire (301-286-7794, mcguire at nssdca.gsfc.nasa.gov). +-------------------------------------------------------------------------+ |To add name to the mailing list, send a message to: editor at igpp.ucla.edu | |For message to whole GEM mailing list, send to: gem at igpp.ucla.edu | | | |URL of GEM Home Page: http://igpp.ucla.edu/gem/Welcome.html | |Please update your e-mail address. | |CAUTION: Do not send messages to gem at igpp.ucla.edu unless you want | | your message to go to everyone in the GEM mailing list! | +-------------------------------------------------------------------------+