The RSIG applet and web servers are conduits for accessing data whose quality is the responsibility of the organizations that produce and maintain the data. When a new dataset is added to RSIG's complement, quality checks are conducted to ensure that the data which RSIG retrieves matches the data from the source files. If a problem is noted concerning the integrity of any dataset, please contact the RSIG team. While data integrity checks have been performed by the RSIG team, not all data provided through RSIG has been independently quality assured by the EPA. Please direct all questions about data quality or related issues to the data source providers listed below.

Archived data may not be immediately available. Data availability depends on such factors as the remote host system's availability, the stability of network connections, and other issues beyond the control of EPA and this application. The RSIG application will display system messages if data is unavailable.

NASA's Moderate Resolution Imaging Spectroradiometer (MODIS) data

• Generally available Aerosol Optical Depth (AOD), Cloud Optical Thickness (COT), ozone, pressure, temperature from 2000 onwards. The following links exit the site Exit
• Provider site: http://ladsweb.nascom.nasa.gov/data/availability.html
• Provider site: http://modis.gsfc.nasa.gov/

AIRNow data, via the AIRNow Gateway

These data are archived at the AIRNow Gateway operated by Sonoma Technology for U.S. EPA's AIRNow Program and accessed on-demand via the DataFed web server: http://webapps.datafed.net/ogc_EPA.wsfl The following is from the AIRNow web site: "These data are not fully verified or validated and should be considered preliminary and subject to change. Data and information reported to AIRNow from federal, state, local and tribal agencies are for the express purpose of reporting and forecasting the Air Quality Index (AQI). As such, they should not be used to formulate or support regulation, trends, guidance, or any other government or public decision making. Official regulatory air quality data must be obtained from EPA's Air Quality System (AQS)."

• GMT hourly ozone, PM2.5 from 2003 onwards.
• Provider site: http://www.airnowgateway.org/ Exit

U.S. EPA's Air Quality System (AQS)

AQS contains data vetted by the states. RSIG accesses AQS data via the AQS Data Mart database.

The AQS Data Mart is a database containing all of the information from the AQS system. Since 2007, it has contained information from AIRNow (the real time air quality reporting system) that participating agencies allow to be shared with the public. Currently the AQS Data Mart has nearly 1.6 billion values-every measured, daily aggregate, and annual aggregate value collected and calculated by EPA since January 01, 1980.

The data in the AQS Data Mart is updated nightly, 5 times per week, from the AQS database so it is the latest available. Eventually it will bring in the real-time AIRNow data each night as well.

Historical data can change at any time. Many quality assurance review processes are made on an entire year's worth of data, so it might not be until the middle of this year until the final review and changes have been made to last year's data by a submitter. Also, historical monitoring or calculation methods may be found to be problematic and require that older data be changed. Finally, there is no "versioning" or freezing of data in the Data Mart, so if other people may need your data exactly as you have it to verify or continue your analysis, you must keep a copy of it.

AQS data takes precedence over AIRNow data. AIRNow data is removed after one year if the data is not updated by AQS.

• GMT hourly ozone and PM2.5, GMT daily average PM2.5, ozone GMT 8-hour average and maximum, temperature, relative humidity, sulfer dioxide from 1980 onward.
• Provider site: AQS Data Mart

U.S. EPA's Community Multiscale Air Quality (CMAQ) model output

Meteorology, gridded emissions, concentrations, depositions, derived PM2.5, NOY, AOD and Extinction

• OAQPS CDC East US 12km 2002-2006 and 12km CONUS 2007-2008. Update, 11/28/2016: CMAQ CDC data is now only aconc.o3 and pm25 layer 1.
• AQMEII 12km CONUS 2006 (restricted access). Update, 11/28/2016: This data is no longer available.
• AMAD Northern Hemisphere 2006 (restricted access). Update, 11/28/2016: CMAQ AMAD data will be renamed CMAQ CED (Computational Exposure Division) and expanded to years 2002-2012 over the next few months.
• Metadata for 2002-2012 12km Continental US (CONUS) Bidirectional confined animal feeding operations (CAFO) CMAQ v5.0.2 Simulations
• Metadata for 2025 12km CONUS Bidirectional-CAFO run of November 2014_v2 – CMAQv5.0.2 Simulations
• Other CMAQ runs will be added as they become available for release.
• Provider site: National Exposure Research Laboratory

NOAA/National Environmental Satellite, Data, and Information Service (NESDIS) biomass burning data

• Biomass burning 2007, PM2.5, CO, CO2, CH4, N2O, NH3, NOx, SO2, TNMHC.
• Provider site: http://www.star.nesdis.noaa.gov/star/AQ_emissions.php. Data accessed at: ftp://ftp.orbit.nesdis.noaa.gov/pub/smcd/xzhang/PM25 Exit

UVNet

• Twenty-two ground stations in the US measuring Irradiance (W/m2) and UVBio "sunburn" (W/m2), 1996 through 2004-06.
• Provider site: UV-Net Data Access (EPA Archive)

NEUBrew

• Six ground Brewer Spectrophotometer stations in the US measuring ozone (molecules/cm3) profiles (26 points up to 51 km) in the morning and evening, since September 2006.
• Provider site: http://www.esrl.noaa.gov/gmd/grad/neubrew/ Exit

Fused Air Quality Surfaces Using Downscaling (FAQSD)

• Based on statistical modeling research in the development of fused space-time predictive surfaces for air quality, a Bayesian space-time downscaler model is used to "fuse" daily ozone (8-hr max) and fine particulate air (24-hr average) monitoring data from the National Air Monitoring Stations/State and Local Air Monitoring Stations (NAMS/SLAMS) with 12 km gridded output from the Models-3/Community Multiscale Air Quality (CMAQ) model. Daily predictions are available at the 2000 US Census Tract centroid locations over the eastern U.S. for 2001-2007.
• Data and metadata: /hesc/rsig-related-downloadable-data-files#faqsd

GOES GASP AOD data (Geostationary Operational Environmental Satellite Aerosol Smoke Product Aerosol Optical Depth)

• More information about GASP data can be found at: http://www.star.nesdis.noaa.gov/star/AQ_goesaod.php Exit

Cloud-Aerosol Lidar and Infrared Pathfinder Satellite Observation (CALIPSO) data

• 2006-07-01 to present.
• Level-1b Backscatter and Depolarization.
• Level-2 Aerosol and Cloud: Backscatter, Extinction, Depolarization, Aerosol/Cloud Layer Fraction and Column Optical Depth (integrated to surface).
• More information about CALIPSO data can be found at: http://www-calipso.larc.nasa.gov Exit
• Note: RSIG conservatively filters the CALIPSO data according to NASA Langley CALIPSO Team recommendations which include:
  1. Valid range of data - which can include slightly negative (non-physical) values required to avoid bias in any subsequent aggregation.
  2. Available/applicable QC flag data (only non-error bits accepted).
  3. Available/corresponding absolute Uncertainty data (user adjustable).
  4. CAD_Score (cloud-aerosol discrimination score) - a measure of the likelyhood of correctly distinguished aerosol/cloud features. (User adjustable).
  5. Includes Uncertainty file (if available) when saving CALIPSO data.
  6. Detailed information about CALIPSO data products can be found at: http://www-calipso.larc.nasa.gov/resources/calipso_users_guide/data_summaries/ Exit
  7. See also CAD/QC filtering at: http://www-calipso.larc.nasa.gov/resources/calipso_users_guide/data_summaries/layer/index.php#cad_score Exit
  8. And Quality Summary Document: https://eosweb.larc.nasa.gov/project/calipso/quality_summaries/CALIOP_L2ProfileProducts_3.01.pdf Exit

Global commercial aircraft measurements: Measurements of OZone, etc. by AIbus airCraft (MOZAIC) data

• Ozone, CO, H2O, temperature, wind, etc.: 2002-01-01 to 2011-12-31.
• MOZAIC has been superceded and absorbed by the In-service Aircraft for a Global Observing System (IAGOS) Data Portal. You need to register on the IAGOS site to access the data.

EPA is working to bring additional data sets into RSIG including:

NASA AURA Ozone Monitoring Instrument (OMI) aerosol and NO2 data

• More information about OMI data can be found at: http://aura.gsfc.nasa.gov/instruments/omi.html Exit

NASA Global Ozone Monitoring Experiment-2 (GOME-2) data

• More information about GOME-2 data to be provided by NOAA can be found at: http://www.star.nesdis.noaa.gov/star/AQ_GOME2.php Exit

NASA MOPITT (Measure Pollution In The Troposphere) CO data: https://eosweb.larc.nasa.gov/project/mopitt/mopitt_table Exit

NASA CERES (Clouds and Earth's Radiant Energy System) data: http://ceres.larc.nasa.gov/ Exit

EPA OAQPS CMAQ data as they become available.

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