Produk NASA Suomi National Polar-Orbiting Partnership (Suomi NPP) Visible Infrared Imaging Radiometer Suite (VIIRS) Land Surface Temperature and Emissivity (LST&E) Night Version 1 (VNP21A1N) dikompilasi setiap hari dari produk perantara Level 2 Gridded (L2G) pada malam hari.
Proses L2G memetakan butiran petak VNP21 harian ke dalam petak MODIS sinusoidal dan menyimpan semua pengamatan yang tumpang-tindih dengan sel petak untuk malam tertentu. Algoritma VNP21A1 memilah semua pengamatan ini untuk setiap
sel dan memperkirakan nilai LST akhir sebagai rata-rata dari semua pengamatan bebas awan
yang memiliki akurasi LST yang baik. Hanya pengamatan yang memiliki cakupan pengamatan lebih dari nilai minimum tertentu (15%) yang dipertimbangkan untuk perhitungan rata-rata ini.
0: Diproduksi oleh Pixel, kualitas bagus, tidak memerlukan info QA lebih lanjut
1: Pixel diproduksi, tetapi kualitasnya tidak dapat diandalkan
2: Pixel tidak diproduksi karena cloud
3: Pixel tidak diproduksi karena alasan selain cloud
Bit 2-3: Flag kualitas data
0: Kualitas data yang baik dari band L1B 14, 15, 16
1: Piksel hilang
2: Cukup terkalibrasi
3: Kalibrasi buruk, pemrosesan TES dilewati
Bit 4-5: Cloud Flag
0: Tanpa awan
1: Cirrus tipis
2: Piksel dalam jarak 2 piksel dari awan terdekat
3: Piksel berawan
Bit 6-7: Iterasi
0: Konvergensi lambat
1: Nominal
2: Nominal
3: Cepat
Bit 8-9: Opasitas Atmosfer
0: ≥3 (Udara hangat dan lembap; atau daratan dingin)
1: 0,2 - 0,3 (Nilai nominal)
2: 0,1 - 0,2 (Nilai nominal)
3: <0,1 (Piksel kering, atau piksel dataran tinggi)
Bit 10-11: MMD
0: >0,15 (Sebagian besar batuan silikat)
1: 0,1 - 0,15 (Batu, pasir, beberapa jenis tanah)
2: 0,03 - 0,1 (Sebagian besar tanah, piksel campuran)
3: <0,03 (Vegetasi, salju, air, es, beberapa jenis tanah)
Bit 12-13: Akurasi emisivitas
0: >0,02 (Performa buruk)
1: 0,015 - 0,02 (Performa marginal)
2: 0,01 - 0,015 (Performa baik)
3: <0,01 (Performa luar biasa)
Bit 14-15: Akurasi LST
0: >2K (Performa buruk)
1: 1.5 - 2 ribu (Performa marginal)
2: 1 - 1,5 Ribu (Performa baik)
3: <1.000 (Performa sangat baik)
Emis_14
meter
Emisivitas M14 harian
Emis_15
meter
Emisivitas M15 harian
Emis_16
meter
Emisivitas M16 harian
View_Angle
deg
meter
Melihat sudut zenit LST
View_Time
j
meter
Waktu pengamatan LST
Persyaratan Penggunaan
Persyaratan Penggunaan
Data NASA LP DAAC dapat diakses secara bebas; namun, saat penulis memublikasikan data ini atau karya yang didasarkan pada data tersebut, penulis diminta untuk mengutip set data dalam teks publikasi dan menyertakan referensi ke set data tersebut dalam daftar referensi.
Produk NASA Suomi National Polar-Orbiting Partnership (Suomi NPP) Visible Infrared Imaging Radiometer Suite (VIIRS) Land Surface Temperature and Emissivity (LST&E) Night Version 1 (VNP21A1N) dikompilasi setiap hari dari produk perantara Berpetak (L2G) Level 2 pada malam hari. Proses L2G memetakan butiran petak VNP21 harian ke petak MODIS sinusoidal …
[null,null,[],[[["\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--2025-08-30T00:00:00Z\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/2025-08-30T00:00:00Z \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)"]]
