{"action":"update","ckan_id":"c932e028-a33f-42f9-8523-ee8e938156f1","date_created":"Sat, 21 Feb 2026 19:20:44 GMT","date_finished":"Sat, 21 Feb 2026 19:20:44 GMT","harvest_job_id":"c99ff44d-72b0-453c-ae66-95e7af67c97e","harvest_source_id":"e8e2f0de-5222-4b6d-8fa2-b6d5f2a03ffd","id":"7510c44d-1abe-4d00-8907-91633ee915c4","identifier":"10.5067/VIIRS/VNP43IA4N.002","parent_identifier":null,"source_hash":"3c785b71c50c8ff7ba0b2a1f5cd3a326c2ebbf593c113589e6a91e0d58b58b72","source_raw":"{\"@type\": \"dcat:Dataset\", \"accessLevel\": \"public\", \"bureauCode\": [\"026:00\"], \"contactPoint\": {\"@type\": \"vcard:Contact\", \"fn\": \"Earthdata Forum\", \"hasEmail\": \"mailto:earthdata-support@nasa.gov\"}, \"description\": \"The VIIRS/NPP Nadir BRDF-Adjusted Reflectance Daily L3 Global 500 m SIN Grid Near Real Time (NRT), short-name VNP43IA4N product provides NBAR estimates at 500 meter (m) resolution. The VNP43IA4N product is produced daily using 16-day VIIRS data (i.e., the current day and the previous 15 days). The view angle effects are removed from the directional reflectances resulting in a stable and consistent Bidirectional Reflectance Distribution Function (BRDF) Adjusted Reflectance (NBAR) product.The VNP43 algorithm uses the RossThick/Li-Sparse-Reciprocal (RTLSR) semi-empirical kernel-driven BRDF model, with the three kernel weights from VNP43IA1N to reconstruct surface anisotropic effects, correcting the directional reflectance to a common view geometry (VNP43IA4N), while also computing integrated black-sky albedo (BSA) at local solar noon and white-sky albedo (WSA) (VNP43IA3N). Researchers can use the BRDF model parameters with a simple polynomial, to obtain black-sky albedo at any solar illumination angle. Likewise, both the BSA and WSA Science Dataset (SDS) layers can be used with a simple polynomial, to manually estimate instantaneous actual albedo (blue-sky albedo). Additional details regarding the methodology are available in the Algorithm Theoretical Basis Document (ATBD) at https://www.umb.edu/editor_uploads/images/school_for_the_environment_cs/Viirs/VIIRS_ATBD_Apr_Jul2017.pdf.The VNP43IA4N product includes six SDS layers for BRDF/Albedo mandatory quality and nadir reflectance for VIIRS imagery bands I1, I2, and I3.\", \"distribution\": [{\"@type\": \"dcat:Distribution\", \"downloadURL\": \"https://earthdata.nasa.gov/earth-observation-data/near-real-time/download-nrt-data/viirs-nrt\", \"format\": \"BIN\", \"mediaType\": \"application/octet-stream\", \"title\": \"Data Information (Unknown Format)\"}, {\"@type\": \"dcat:Distribution\", \"downloadURL\": \"https://nrt4.modaps.eosdis.nasa.gov/archive/allData/5200/VNP43IA4N/\", \"format\": \"BIN\", \"mediaType\": \"application/octet-stream\", \"title\": \"Data Information (Unknown Format)\"}], \"identifier\": \"10.5067/VIIRS/VNP43IA4N.002\", \"keyword\": [\"earth-science-surface-radiative-properties-land-surface-albedo\", \"earth-science-surface-radiative-properties-land-surface-anisotropy\"], \"landingPage\": \"https://nrt4.modaps.eosdis.nasa.gov/archive/allData/5200/VNP43IA4N/\", \"modified\": \"2026-02-17\", \"programCode\": [\"026:000\"], \"publisher\": {\"@type\": \"org:Organization\", \"name\": \"NASA/GSFC/SED/ESD/TISL/MODAPS\"}, \"spatial\": \"[\\\"CARTESIAN\\\",[{\\\"NorthBoundingCoordinate\\\":80,\\\"WestBoundingCoordinate\\\":-180,\\\"EastBoundingCoordinate\\\":180,\\\"SouthBoundingCoordinate\\\":-80}]]\", \"temporal\": \"2023-11-20/2023-11-20\", \"theme\": [\"Earth Science\"], \"title\": \"VIIRS/NPP Nadir BRDF-Adjusted Reflectance Daily L3 Global 500m SIN Grid NRT\"}","source_transform":null,"status":"success"}