The NASA Suomi National Polar-Orbiting Partnership (Suomi NPP) Visible
Infrared Imaging Radiometer Suite (VIIRS) Land Surface Temperature and
Emissivity (LST&E) Night Version 1 product (VNP21A1N) is compiled daily
from nighttime Level 2 Gridded (L2G) intermediate products.
The L2G process maps the daily VNP21 swath granules onto a sinusoidal MODIS
grid and stores all observations overlapping a gridded cell for a given
night. The VNP21A1 algorithm sorts through all these observations for each
cell and estimates the final LST value as an average from all cloud-free
observations that have good LST accuracies. Only observations having
observation coverage more than a certain threshold (15%) are considered for
this averaging.
0: Pixel produced, good quality, no further QA info necessary
1: Pixel produced but unreliable quality
2: Pixel not produced due to cloud
3: Pixel not produced due to reasons other than cloud
Bits 2-3: Data quality flag
0: Good data quality of L1B bands 14, 15, 16
1: Missing pixel
2: Fairly calibrated
3: Poorly calibrated, TES processing skipped
Bits 4-5: Cloud Flag
0: Cloud-free
1: Thin cirrus
2: Pixel within 2 pixels of nearest cloud
3: Cloudy pixels
Bits 6-7: Iterations
0: Slow convergence
1: Nominal
2: Nominal
3: Fast
Bits 8-9: Atmospheric Opacity
0: ≥3 (Warm, humid air; or cold land)
1: 0.2 - 0.3 (Nominal value)
2: 0.1 - 0.2 (Nominal value)
3: <0.1 (Dry, or high altitude pixel)
Bits 10-11: MMD
0: >0.15 (Most silicate rocks)
1: 0.1 - 0.15 (Rocks, sand, some soils)
2: 0.03 - 0.1 (Mostly soils, mixed pixel)
3: <0.03 (Vegetation, snow, water, ice, some soils)
Bits 12-13: Emissivity accuracy
0: >0.02 (Poor performance)
1: 0.015 - 0.02 (Marginal performance)
2: 0.01 - 0.015 (Good performance)
3: <0.01 (Excellent performance)
Bits 14-15: LST accuracy
0: >2K (Poor performance)
1: 1.5 - 2K (Marginal performance)
2: 1 - 1.5K (Good performance)
3: <1K (Excellent performance)
Emis_14
meters
Daily M14 emissivity
Emis_15
meters
Daily M15 emissivity
Emis_16
meters
Daily M16 emissivity
View_Angle
deg
meters
View zenith angle of LST
View_Time
h
meters
Time of LST observation
Terms of Use
Terms of Use
LP DAAC NASA data are freely accessible; however, when an author
publishes these data or works based on the data, it is requested that the
author cite the datasets within the text of the publication and include a
reference to them in the reference list.
The NASA Suomi National Polar-Orbiting Partnership (Suomi NPP) Visible Infrared Imaging Radiometer Suite (VIIRS) Land Surface Temperature and Emissivity (LST&E) Night Version 1 product (VNP21A1N) is compiled daily from nighttime Level 2 Gridded (L2G) intermediate products. The L2G process maps the daily VNP21 swath granules onto a sinusoidal MODIS grid …
[[["Easy to understand","easyToUnderstand","thumb-up"],["Solved my problem","solvedMyProblem","thumb-up"],["Other","otherUp","thumb-up"]],[["Missing the information I need","missingTheInformationINeed","thumb-down"],["Too complicated / too many steps","tooComplicatedTooManySteps","thumb-down"],["Out of date","outOfDate","thumb-down"],["Samples / code issue","samplesCodeIssue","thumb-down"],["Other","otherDown","thumb-down"]],[],[[["\u003cp\u003eThe NASA VIIRS VNP21A1N dataset provides daily nighttime land surface temperature and emissivity data at a 1km resolution.\u003c/p\u003e\n"],["\u003cp\u003eThe dataset is derived from the Suomi NPP satellite and covers the period from January 19, 2012, to December 10, 2024.\u003c/p\u003e\n"],["\u003cp\u003eLand surface temperature is estimated by averaging cloud-free observations with good LST accuracies, using only observations with coverage greater than 15%.\u003c/p\u003e\n"],["\u003cp\u003eAlongside temperature, the dataset includes quality control information, emissivity bands, view angle, and view time.\u003c/p\u003e\n"],["\u003cp\u003eUsers are requested to cite the dataset and associated documentation when publishing results based on this data.\u003c/p\u003e\n"]]],[],null,["Dataset Availability\n: 2012-01-19T00:00:00Z--2025-09-05T00:00:00Z\n\nDataset Provider\n:\n\n\n [NASA LP DAAC at the USGS EROS Center](https://doi.org/10.5067/VIIRS/VNP21A1N.002)\n\nCadence\n: 1 Day\n\nTags\n:\n[climate](/earth-engine/datasets/tags/climate) [daily](/earth-engine/datasets/tags/daily) [land](/earth-engine/datasets/tags/land) [nasa](/earth-engine/datasets/tags/nasa) [night](/earth-engine/datasets/tags/night) [noaa](/earth-engine/datasets/tags/noaa) [surface](/earth-engine/datasets/tags/surface) [temperature](/earth-engine/datasets/tags/temperature) [viirs](/earth-engine/datasets/tags/viirs) \n\nDescription \nThe NASA Suomi National Polar-Orbiting Partnership (Suomi NPP) Visible\nInfrared Imaging Radiometer Suite (VIIRS) Land Surface Temperature and\nEmissivity (LST\\&E) Night Version 1 product (VNP21A1N) is compiled daily\nfrom nighttime Level 2 Gridded (L2G) intermediate products.\n\nThe L2G process maps the daily VNP21 swath granules onto a sinusoidal MODIS\ngrid and stores all observations overlapping a gridded cell for a given\nnight. The VNP21A1 algorithm sorts through all these observations for each\ncell and estimates the final LST value as an average from all cloud-free\nobservations that have good LST accuracies. Only observations having\nobservation coverage more than a certain threshold (15%) are considered for\nthis averaging.\n\nDocumentation:\n\n- [User's Guide](https://lpdaac.usgs.gov/documents/429/VNP21_User_Guide_V1.pdf)\n\n- [Algorithm Theoretical Basis Document (ATBD)](https://lpdaac.usgs.gov/documents/1332/VNP21_ATBD_V1.pdf)\n\n- [General Documentation](https://lpdaac.usgs.gov/products/vnp21a1nv002/)\n\n- [Land Product Quality Assessment website](https://landweb.modaps.eosdis.nasa.gov/browse?sensor=VIIRS&sat=SNPP)\n\nBands\n\n\n**Pixel Size**\n\n1000 meters\n\n**Bands**\n\n| Name | Units | Pixel Size | Description |\n|--------------|-------|------------|----------------------------------------------|---|---|---|---|---|---|---|---|---|---|---|---|---|---|---|---|---|---|---|---|---|---|---|---|---|---|---|---|---|---|---|---|---|---|---|---|---|---|---|---|---|---|---|---|---|---|---|---|---|---|---|---|---|---|---|---|---|---|---|---|---|---|---|---|---|---|---|---|---|---|---|---|---|---|---|---|---|---|---|---|---|---|---|---|---|---|---|---|---|---|---|---|---|---|---|---|\n| `LST_1KM` | K | meters | Daily 1 km Land Surface Temperature. |\n| `QC` | | meters | Daily Quality control for LST and emissivity |\n| Bitmask for QC - Bits 0-1: Mandatory QA flags - 0: Pixel produced, good quality, no further QA info necessary - 1: Pixel produced but unreliable quality - 2: Pixel not produced due to cloud - 3: Pixel not produced due to reasons other than cloud - Bits 2-3: Data quality flag - 0: Good data quality of L1B bands 14, 15, 16 - 1: Missing pixel - 2: Fairly calibrated - 3: Poorly calibrated, TES processing skipped - Bits 4-5: Cloud Flag - 0: Cloud-free - 1: Thin cirrus - 2: Pixel within 2 pixels of nearest cloud - 3: Cloudy pixels - Bits 6-7: Iterations - 0: Slow convergence - 1: Nominal - 2: Nominal - 3: Fast - Bits 8-9: Atmospheric Opacity - 0: ≥3 (Warm, humid air; or cold land) - 1: 0.2 - 0.3 (Nominal value) - 2: 0.1 - 0.2 (Nominal value) - 3: \\\u003c0.1 (Dry, or high altitude pixel) - Bits 10-11: MMD - 0: \\\u003e0.15 (Most silicate rocks) - 1: 0.1 - 0.15 (Rocks, sand, some soils) - 2: 0.03 - 0.1 (Mostly soils, mixed pixel) - 3: \\\u003c0.03 (Vegetation, snow, water, ice, some soils) - Bits 12-13: Emissivity accuracy - 0: \\\u003e0.02 (Poor performance) - 1: 0.015 - 0.02 (Marginal performance) - 2: 0.01 - 0.015 (Good performance) - 3: \\\u003c0.01 (Excellent performance) - Bits 14-15: LST accuracy - 0: \\\u003e2K (Poor performance) - 1: 1.5 - 2K (Marginal performance) - 2: 1 - 1.5K (Good performance) - 3: \\\u003c1K (Excellent performance) ||||||||||||||||||||||||||||||||||||||||||||||||||||||||||||||||||||||||||||||||||||||||||||||||||||\n| `Emis_14` | | meters | Daily M14 emissivity |\n| `Emis_15` | | meters | Daily M15 emissivity |\n| `Emis_16` | | meters | Daily M16 emissivity |\n| `View_Angle` | deg | meters | View zenith angle of LST |\n| `View_Time` | h | meters | Time of LST observation |\n\nTerms of Use\n\n**Terms of Use**\n\nLP DAAC NASA data are freely accessible; however, when an author\npublishes these data or works based on the data, it is requested that the\nauthor cite the datasets within the text of the publication and include a\nreference to them in the reference list.\n\nCitations \nCitations:\n\n- Please visit [LP DAAC 'Citing Our Data' page](https://lpdaac.usgs.gov/citing_our_data)\n for information on citing LP DAAC datasets.\n\nDOIs\n\n- \u003chttps://doi.org/10.5067/VIIRS/VNP21A1N.002\u003e\n\nExplore with Earth Engine **Important:** Earth Engine is a platform for petabyte-scale scientific analysis and visualization of geospatial datasets, both for public benefit and for business and government users. Earth Engine is free to use for research, education, and nonprofit use. To get started, please [register for Earth Engine access.](https://console.cloud.google.com/earth-engine)\n\nCode Editor (JavaScript) \n\n```javascript\nvar dataset = ee.ImageCollection('NASA/VIIRS/002/VNP21A1N')\n .filter(ee.Filter.date('2022-11-01', '2022-12-01'));\n\nvar visualization = {\n bands: ['LST_1KM'],\n min: [150],\n max: [300],\n palette: [\n 'a50026',\n 'd73027',\n 'f46d43',\n 'fdae61',\n 'fee08b',\n 'ffffbf',\n 'd9ef8b',\n 'a6d96a',\n '66bd63',\n '1a9850',\n '006837',\n ]\n};\nMap.setCenter(41.2, 38.84, 3);\nMap.addLayer(dataset, visualization, 'LST');\n```\n[Open in Code Editor](https://code.earthengine.google.com/?scriptPath=Examples:Datasets/NASA/NASA_VIIRS_002_VNP21A1N) \n[VNP21A1N.002: Night Land Surface Temperature and Emissivity Daily 1km](/earth-engine/datasets/catalog/NASA_VIIRS_002_VNP21A1N) \nThe NASA Suomi National Polar-Orbiting Partnership (Suomi NPP) Visible Infrared Imaging Radiometer Suite (VIIRS) Land Surface Temperature and Emissivity (LST\\&E) Night Version 1 product (VNP21A1N) is compiled daily from nighttime Level 2 Gridded (L2G) intermediate products. The L2G process maps the daily VNP21 swath granules onto a sinusoidal MODIS grid ... \nNASA/VIIRS/002/VNP21A1N, climate,daily,land,nasa,night,noaa,surface,temperature,viirs \n2012-01-19T00:00:00Z/2025-09-05T00:00:00Z \n-90 -180 90 180 \nGoogle Earth Engine \nhttps://developers.google.com/earth-engine/datasets\n\n- [https://doi.org/10.5067/VIIRS/VNP21A1N.002](https://doi.org/https://doi.org/10.5067/VIIRS/VNP21A1N.002)\n- [https://doi.org/10.5067/VIIRS/VNP21A1N.002](https://doi.org/https://developers.google.com/earth-engine/datasets/catalog/NASA_VIIRS_002_VNP21A1N)"]]
