Remote Sensing Information Gateway (RSIG)

From Earth Science Information Partners (ESIP)

The Remote Sensing Information Gateway (RSIG) is a tool for selecting, downloading, assembling, and visualizing atmospheric data. After the data has been assembled, it can be stored on the user’s workstation, if desired. RSIG is developed by the US Environmental Protection Agency (EPA); see File:Rsig 10312007.pdf .

The RSIG application is operated by selecting from among fifteen or so variables available from the following data sources:

  • NASA's Moderate Resolution Imaging Spectroradiometer (MODIS) and Cloud-Aerosol Lidar and Infrared Pathfinder Satellite Observation (CALIPSO) data
  • Sonoma Tech's AIRNow and NOAA's Air Quality System (AQS) ozone and particulate-matter observations
  • EPA's Community Multiscale Air Quality (CMAQ) model output
  • National Environmental Satellite, Data, and Information Service (NESDIS) biomass burning data

More details on RSIG's data sources can be found at http://linden.nesc.epa.gov/rsig/datainventory.html.

The application then assembles the data from local files or by submitting requests over the Internet to data repositories at NASA, NOAA, etc. RSIG then presents a visualization of the data on a latitude-longitude map, automatically locating the data in correct geographic position.

RSIG uses program code that runs on NASA and NOAA servers to select and subset large datasets at the source computer center. Transmission over the Internet to the EPA is thereby accelerated compared to conventional techniques.

RSIG can save the collected data in the following formats:

  • Binary External Data Representation (XDR) format
  • NetCDF format
  • ASCII spreadsheet
  • MPEG or PNG format files for visualized images


Access and Status

The RSIG documentation server is on the EPA Intranet at http://linden.nesc.epa.gov/rsig. The RSIG application is operable but is still in the final stages of development. As of May 2007, the application can be accessed at http://rtpmeta.epa.gov/portal/rsig2D.html. All workstation users connected to the EPA network can access these servers. Those outside of the EPA network do not have access.

Java Requirements

RSIG is a Web browser-based application that runs as a Java applet. Therefore, RSIG carries the following Java requirements:

  • Java Runtime Environment (JRE) 1.4 or better
  • a .java.policy file saved to your Home directory. The .java.policy file is a simple text file that ensures you can save data from the RSIG applet to your computer.

The RSIG web site contains full information on installing the .java.policy file for Linus, UNIX, Mac OS, and Windows systems here: http://linden.nesc.epa.gov/rsig/javapolicy.html.

Access to RSIG Data

In addition to the Web browser-based Java applet, RSIG offers additional ways for researchers or applications to access data.

Streaming access. Applications with specific information needs can use RSIG's CGI scripts to enable streaming access to RSIG's data. This can effectively automate access to any data that RSIG can access and deliver the data to your application in the desired format. These scripts are in the review process, but are accessible within the EPA intranet. For more information: http://linden.nesc.epa.gov/rsig/rsig_cgi.html

Web server scripts. Assuming your application is running on an EPA computer inside the EPA firewall, then the application should access http://maple.rtpnc.epa.gov, which is the internal computer containing the web server scripts. (Tthe MODIS script is on a public NASA computer.) The scripts will eventually be hosted on external EPA computers for external/non-EPA clients. The server scripts are OGC-WCS-compliant. For more information: http://linden.nesc.epa.gov/rsig/webscripts.html

Sponsorship and Contacts

The RSIG application has been sponsored and managed by ORD’s National Exposure Research Lab (NERL). Dr. Fred Dimmick, Chief of the Process Modeling Research Branch, is the responsible EPA manager. It is being developed by the EPA Environmental Modeling and Visualization Laboratory (EMVL).

  • Dr. Fred Dimmick, dimmick.fred@epa.gov, EPA ORD (919) 541-5537
  • Dr. Joe Retzer, retzer.joseph@epa.gov, EPA NCC (919) 541-4190
  • For technical information contact: Mike Uhl EPA EMVL (Lockheed Martin) 919-541-4283.