{"@type": "dcat:Dataset", "accessLevel": "public", "bureauCode": ["026:00"], "contactPoint": {"@type": "vcard:Contact", "fn": "undefined", "hasEmail": "mailto:uso@daac.ornl.gov"}, "description": "This dataset provides the annual date of snowpack seasonal beginning melt (i.e., main melt onset date, MMOD) across northwest Canada; Alaska, U.S.; and parts of far eastern Russia at 6.25 km resolution for the period 1988-2018. MMOD was derived from the daily 19V (K-band) and 37V (Ka-band) GHz bands from the Making Earth Science Data Records for Use in Research Environments (MEaSUREs) Calibrated Enhanced-Resolution Passive Microwave (PMW) EASE-Grid Brightness Temperature (Tb) Earth System Data Record (ESDR). The PMW MMOD dataset was validated using the transition date from Freeze Degree Days (FDD) to Thaw Degree Days (TDD) from in situ air temperature observations from 31 SNOw TELemetry network (SNOTEL) observations, and compared to the established Freeze-Thaw ESDR (FT-ESDR) spring onset date. The resulting MMOD data record is suitable for documenting the spatial-temporal impacts of MMOD variability in ecosystem services, wildlife movements, and hydrologic processes across the ABoVE domain. The data from 1988-2016 included a coastal mask removing coastal pixels due to potential water contamination from coarse brightness temperature observations (Dersken et al., 2012). There is not a coastal mask for the 2017-2018 data. The full data are included, and data users should be aware that coastal values can be adversely affected by adjacent water bodies.", "distribution": [{"@type": "dcat:Distribution", "description": "ABoVE project site", "downloadURL": "https://above.nasa.gov", "format": "HTML", "mediaType": "text/html", "title": "The dataset's project home page"}, {"@type": "dcat:Distribution", "description": "ABoVE: Passive Microwave-derived Annual Snowpack Main Melt Onset Date Maps, 1988-2018: Main_Melt_Onset_Dates.pdf", "downloadURL": "https://data.ornldaac.earthdata.nasa.gov/public/above/Main_Melt_Onset_Dates/comp/Main_Melt_Onset_Dates.pdf", "format": "PDF", "mediaType": "application/pdf", "title": "View documentation related to this dataset"}, {"@type": "dcat:Distribution", "description": "Data set Landing Page DOI URL", "downloadURL": "https://doi.org/10.3334/ORNLDAAC/1841", "format": "HTML", "mediaType": "text/html", "title": "This dataset's landing page"}, {"@type": "dcat:Distribution", "description": "ORNL DAAC Data Set Documentation", "downloadURL": "https://daac.ornl.gov/ABOVE/guides/Main_Melt_Onset_Dates.html", "format": "HTML", "mediaType": "text/html", "title": "View documentation related to this dataset"}, {"@type": "dcat:Distribution", "description": "Search results for publications that cite this dataset by its DOI.", "downloadURL": "https://scholar.google.com/scholar?q=10.3334%2FORNLDAAC%2F1841", "format": "HTML", "mediaType": "text/html", "title": "Google Scholar search results"}, {"@type": "dcat:Distribution", "description": "Spatial extent of snowpack main melt onset dataset (MMOD) extending from the Russian Far East across Alaska into Canada's Northwest Territories and British Columbia. The map also includes the GRDC river gauging locations (blue diamonds) used at Eagle, Stevens Village, and Pilot basins (black outlines). Locations of river ice breakup observations (white circles), the World Meteorological Organization (WMO) stations (orange triangles), and SNOw TELemetry network (SNOTEL) stations (purple triangles) are shown. Source: Pan et al. (2021)", "downloadURL": "https://daac.ornl.gov/ABOVE/guides/Main_Melt_Onset_Dates_Fig1.jpg", "format": "JPEG", "mediaType": "image/jpeg", "title": "Get a related visualization"}, {"@type": "dcat:Distribution", "description": "This link allows direct data access via Earthdata login", "downloadURL": "https://daac.ornl.gov/daacdata/above/Main_Melt_Onset_Dates/", "format": "HTML", "mediaType": "text/html", "title": "Download this dataset"}], "identifier": "C2143401742-ORNL_CLOUD", "issued": "2024-05-01", "keyword": ["climate-indicators", "cryosphere", "cryospheric-indicators", "earth-science", "snow-ice", "terrestrial-hydrosphere"], "landingPage": "https://doi.org/10.3334/ORNLDAAC/1841", "language": ["en-US"], "modified": "2025-04-23", "programCode": ["026:001"], "publisher": {"@type": "org:Organization", "name": "ORNL_DAAC"}, "spatial": "-180.0 51.61 -107.83 72.41", "temporal": "1988-02-09T00:00:00Z/2018-02-10T23:59:59Z", "theme": ["ABoVE", "geospatial"], "title": "ABoVE: Passive Microwave-derived Annual Snowpack Main Melt Onset Date Maps, 1988-2018"}