{"@type": "dcat:Dataset", "accessLevel": "public", "bureauCode": ["026:00"], "contactPoint": {"@type": "vcard:Contact", "fn": "Earthdata Forum", "hasEmail": "mailto:earthdata-support@nasa.gov"}, "description": "This product provides MERRA-2 bias-corrected global hourly surface total PM2.5 mass concentration with the same horizontal spatial resolution as MERRA-2, covering a temporal range from 2000 to 2024. It is derived using a machine learning (ML) approach with a convolutional neural network (CNN) method and is specifically developed for the NASA Health and Air Quality Applied Sciences Team (HAQAST).\n\nThe dataset consists of two parameters: MERRA2_CNN_Surface_PM25 and QFLAG. MERRA2_CNN_Surface_PM25, a 3-dimensional variable (time, latitude, longitude), represents the surface PM2.5 concentrations in \u00b5g/m\u00b3. QFLAG denotes the quality of data at each grid point, where 4 indicates the highest quality and 1 indicates the lowest quality. It is recommended to use QFLAG values of 3 and 4 for quantitative analysis.", "distribution": [{"@type": "dcat:Distribution", "conformsTo": "http://www.isotc211.org/2005/gmi", "description": "The metadata's original source.", "downloadURL": "https://cmr.earthdata.nasa.gov/search/concepts/C3094710982-GES_DISC.iso19115", "format": "ISO", "mediaType": "text/xml", "title": "Original Metadata"}, {"@type": "dcat:Distribution", "downloadURL": "https://acdisc.gesdisc.eosdis.nasa.gov/data/HAQAST/MERRA2_CNN_HAQAST_PM25.1", "format": "BIN", "mediaType": "application/octet-stream"}, {"@type": "dcat:Distribution", "downloadURL": "https://acdisc.gesdisc.eosdis.nasa.gov/opendap/HAQAST/MERRA2_CNN_HAQAST_PM25.1/contents.html", "format": "HTML", "mediaType": "text/html"}, {"@type": "dcat:Distribution", "downloadURL": "https://disc.gsfc.nasa.gov/datacollection/MERRA2_CNN_HAQAST_PM25_1.html", "format": "HTML", "mediaType": "text/html"}, {"@type": "dcat:Distribution", "downloadURL": "https://disc.gsfc.nasa.gov/information/howto", "format": "BIN", "mediaType": "application/octet-stream"}, {"@type": "dcat:Distribution", "downloadURL": "https://docserver.gesdisc.eosdis.nasa.gov/public/project/HAQAST/Pawan_Gupta/README_MERRA2_CNN_HAQAST_PM25_V1.pdf", "format": "PDF", "mediaType": "application/pdf"}, {"@type": "dcat:Distribution", "downloadURL": "https://docserver.gesdisc.eosdis.nasa.gov/public/project/Images/MERRA2_CNN_HAQAST_PM25_1.png", "format": "PNG", "mediaType": "image/png"}, {"@type": "dcat:Distribution", "downloadURL": "https://giovanni.gsfc.nasa.gov/giovanni/#dataKeyword=MERRA2_CNN_HAQAST_PM25", "format": "BIN", "mediaType": "application/octet-stream"}, {"@type": "dcat:Distribution", "downloadURL": "https://github.com/Alqamah-Sayeed/MERRA2-ML-PM2.5/", "format": "BIN", "mediaType": "application/octet-stream"}, {"@type": "dcat:Distribution", "downloadURL": "https://search.earthdata.nasa.gov/search/granules?p=C3094710982-GES_DISC", "format": "BIN", "mediaType": "application/octet-stream"}], "identifier": "10.5067/OCKK5HCFW5N3", "keyword": ["earth-science-aerosols-atmosphere-particulate-matter", "earth-science-air-quality-atmosphere", "earth-science-public-health-human-dimensions-environmental-health-factors"], "license": "https://www.usa.gov/government-works", "modified": "2026-06-23", "programCode": ["026:000"], "publisher": {"@type": "org:Organization", "name": "NASA/GSFC/SED/ESD/TISL/GESDISC"}, "spatial": "[\"CARTESIAN\", [{\"WestBoundingCoordinate\": -180, \"NorthBoundingCoordinate\": 90, \"EastBoundingCoordinate\": 180, \"SouthBoundingCoordinate\": -90}]]", "temporal": "2000-01-01/2026-06-15", "theme": ["Earth Science"], "title": "MERRA2_CNN_HAQAST bias corrected global hourly surface total PM2.5 mass concentration, V1 (MERRA2_CNN_HAQAST_PM25) at GES DISC"}