Produk data Indeks Vegetasi (VNP13A1) Visible Infrared Imaging Radiometer Suite (VIIRS) NASA Suomi National Polar-Orbiting Partnership (S-NPP) menyediakan indeks vegetasi dengan proses memilih piksel terbaik yang tersedia selama periode akuisisi 16 hari pada resolusi 500 meter. Produk data VNP13 dirancang
setelah rangkaian produk Moderate Resolution Imaging Spectroradiometer (MODIS)
Terra dan Aqua Vegetation Indices untuk mempromosikan
kelangsungan misi Earth Observation System (EOS).
Proses algoritma VNP13 menghasilkan tiga indeks vegetasi: (1)
Normalized Difference Vegetation Index (NDVI), (2) Enhanced
Vegetation Index (EVI), dan (3) Enhanced Vegetation Index-2 (EVI2).
(1) NDVI adalah salah satu pengamatan deret waktu yang berkelanjutan dan paling lama yang diindera dari jarak jauh, menggunakan band merah dan inframerah dekat (NIR).
(2) EVI adalah indeks vegetasi yang sedikit berbeda dan lebih sensitif terhadap tutupan tajuk, sedangkan NDVI lebih sensitif terhadap klorofil. (3) EVI2
adalah reformasi EVI 3-band standar, menggunakan band merah dan
band NIR. Reformasi ini mengatasi masalah yang muncul saat membandingkan
EVI VIIRS dengan model EVI lain yang tidak menyertakan band biru. EVI2
pada akhirnya akan menjadi EVI standar.
Selain tiga lapisan Indeks Vegetasi, produk ini juga
mencakup lapisan untuk pantulan inframerah dekat (NIR); tiga pantulan inframerah gelombang pendek (SWIR)-pantulan merah, biru, dan hijau; gabungan
hari dalam setahun; keandalan piksel; sudut pandang dan matahari, serta lapisan kualitas.
3: Pixel tidak diproduksi karena alasan lain selain awan
Bit 2-5: Kegunaan VI, nilai yang lebih tinggi lebih buruk.
0: Kualitas Tertinggi
1: Kualitas lebih rendah
2: Menurunkan kualitas
3: Menurunkan kualitas
4: Menurunkan kualitas
5: Kualitas menurun
6: Menurunkan kualitas
7: Menurunkan kualitas
8: Menurunkan kualitas
9: Menurunkan kualitas
10: Menurunkan kualitas
11: Menurunkan kualitas
12: Kualitas terburuk
13: Kualitas sangat rendah sehingga tidak berguna
14: Data L1B rusak
15: Tidak berguna karena alasan apa pun/tidak diproses
Bit 6-7: Jumlah aerosol
0: Klimatologi
1: Rendah
2: Rata-Rata
3: Tinggi
Bit 8: Cloud di sekitar terdeteksi
0: Tidak
1: Ya
Bit 9: Koreksi BRDF berdekatan dilakukan
0: Tidak
1: Ya
Bit 10: Cloud campuran
0: Tidak
1: Ya
Bit 11-13: Bendera Darat/Air
0: daratan & gurun
1: daratan tanpa gurun
2: perairan pedalaman
3: sea_water
5: pesisir
Bit 14: Kemungkinan salju/es
0: Tidak
1: Ya
Bit 15: Kemungkinan bayangan
0: Tidak
1: Ya
red_reflectance
meter
600-680nm
Reflektansi band merah
green_reflectance
meter
545-656nm
Reflektansi band hijau
blue_reflectance
meter
478-498nm
Pantulan pita biru
composite_day_of_the_year
d
meter
Tidak ada
Hari Julian dalam setahun
pixel_reliability
meter
Tidak ada
Kegunaan Pixel menggunakan class peringkat sederhana
relative_azimuth_angle
deg
meter
Tidak ada
Sudut azimut relatif untuk setiap piksel
sun_zenith_angle
deg
meter
Tidak ada
Sudut zenit matahari untuk setiap piksel
view_zenith_angle
deg
meter
Tidak ada
Melihat sudut zenit untuk setiap piksel
Tabel Kelas pixel_reliability
Nilai
Warna
Deskripsi
0
Tidak ada
Luar biasa
1
Tidak ada
Baik
2
Tidak ada
Dapat diterima
3
Tidak ada
Marginal
4
Tidak ada
Lulus
5
Tidak ada
Meragukan
6
Tidak ada
Buruk
7
Tidak ada
Cloud Shadow
8
Tidak ada
Salju/Es
9
Tidak ada
Cloud
10
Tidak ada
Estimasi
11
Tidak ada
LTAVG (diambil dari database)
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 data Suomi National Polar-Orbiting Partnership (S-NPP) NASA Visible Infrared Imaging Radiometer Suite (VIIRS) Vegetation Indices (VNP13A1) menyediakan indeks vegetasi dengan proses memilih piksel terbaik yang tersedia selama periode akuisisi 16 hari pada resolusi 500 meter. Produk data VNP13 dirancang setelah Moderate Resolution Imaging …
[null,null,[],[[["\u003cp\u003eThe NASA VIIRS VNP13A1 dataset provides vegetation indices (NDVI, EVI, EVI2) and reflectance data at 500m resolution over 16-day periods.\u003c/p\u003e\n"],["\u003cp\u003eThis dataset, available from 2012-01-17 to 2024-11-24, is designed for continuity with MODIS vegetation indices products.\u003c/p\u003e\n"],["\u003cp\u003eVNP13A1 includes quality assessment layers for pixel reliability, view and sun angles, and potential cloud or snow/ice presence.\u003c/p\u003e\n"],["\u003cp\u003eThe dataset is freely accessible through NASA LP DAAC and is easily integrated into Google Earth Engine for analysis.\u003c/p\u003e\n"],["\u003cp\u003eUsers are requested to cite the dataset appropriately in publications using data derived from this product.\u003c/p\u003e\n"]]],[],null,["Dataset Availability\n: 2012-01-17T00:00:00Z--2025-08-05T00:00:00Z\n\nDataset Provider\n:\n\n\n [NASA LP DAAC at the USGS EROS Center](https://doi.org/10.5067/VIIRS/VNP13A1.002)\n\nCadence\n: 8 Days\n\nTags\n:\n [16-day](/earth-engine/datasets/tags/16-day) [evi](/earth-engine/datasets/tags/evi) [nasa](/earth-engine/datasets/tags/nasa) [ndvi](/earth-engine/datasets/tags/ndvi) [noaa](/earth-engine/datasets/tags/noaa) [npp](/earth-engine/datasets/tags/npp) [vegetation](/earth-engine/datasets/tags/vegetation) [vegetation-indices](/earth-engine/datasets/tags/vegetation-indices) [viirs](/earth-engine/datasets/tags/viirs) \nvnp13a1 \n\nDescription \nThe Suomi National Polar-Orbiting Partnership (S-NPP) NASA Visible\nInfrared Imaging Radiometer Suite (VIIRS) Vegetation Indices (VNP13A1)\ndata product provides vegetation indices by a process of\nselecting the best available pixel over a 16-day acquisition period\nat 500 meter resolution. The VNP13 data products are designed\nafter the Moderate Resolution Imaging Spectroradiometer (MODIS)\nTerra and Aqua Vegetation Indices product suite to promote the\ncontinuity of the Earth Observation System (EOS) mission.\n\nThe VNP13 algorithm process produces three vegetation indices: (1)\nNormalized Difference Vegetation Index (NDVI), (2) the Enhanced\nVegetation Index (EVI), and (3) Enhanced Vegetation Index-2 (EVI2).\n(1) NDVI is one of the longest continual remotely sensed time series\nobservations, using both the red and near-infrared (NIR) bands.\n(2) EVI is a slightly different vegetation index that is more sensitive\nto canopy cover, while NDVI is more sensitive to chlorophyll. (3) EVI2\nis a reformation of the standard 3-band EVI, using the red band and\nNIR band. This reformation addresses arising issues when comparing\nVIIRS EVI to other EVI models that do not include a blue band. EVI2\nwill eventually become the standard EVI.\n\nAlong with the three Vegetation Indices layers, this product also\nincludes layers for near-infrared (NIR) reflectance; three shortwave\ninfrared (SWIR) reflectance-red, blue, and green reflectance; composite\nday of year; pixel reliability; view and sun angles, and a quality layer.\n\nFor additional information, visit the VIIRS [Land Product Quality\nAssessment website](https://landweb.modaps.eosdis.nasa.gov/browse?sensor=VIIRS&sat=SNPP) and see\nthe [User Guide](https://lpdaac.usgs.gov/documents/1372/VNP13_User_Guide_ATBD_V2.1.2.pdf).\n\nDocumentation:\n\n- [General Documentation](https://ladsweb.modaps.eosdis.nasa.gov/filespec/VIIRS/1/VNP13A1)\n\nBands\n\n\n**Pixel Size**\n\n500 meters\n\n**Bands**\n\n| Name | Units | Pixel Size | Wavelength | Description |\n|-----------------------------|-------|------------|-------------|--------------------------------------------|---|---|---|---|---|---|---|---|---|---|---|---|---|---|---|---|---|---|---|---|---|---|---|---|---|---|---|---|---|---|---|---|---|---|---|---|---|---|---|---|---|---|---|---|---|---|---|---|---|---|---|---|---|---|---|---|---|---|---|---|---|---|---|---|---|---|---|---|---|---|---|---|---|---|---|---|---|---|---|---|---|---|---|---|---|---|---|---|---|---|---|---|---|---|---|\n| `EVI` | | meters | None | 3 band Enhanced Vegetation Index |\n| `EVI2` | | meters | None | 2 band Enhanced Vegetation Index |\n| `NDVI` | | meters | None | Normalized Difference Vegetation Index |\n| `NIR_reflectance` | | meters | 846-885nm | Near-infrared Radiation reflectance |\n| `SWIR1_reflectance` | | meters | 1230-1250nm | Shortwave Infrared Radiation reflectance |\n| `SWIR2_reflectance` | | meters | 1580-1640nm | Shortwave Infrared Radiation reflectance |\n| `SWIR3_reflectance` | | meters | 2225-2275nm | Shortwave Infrared Radiation reflectance |\n| `VI_Quality` | | meters | None | Quality Assessment (QA) bit-field. |\n| Bitmask for VI_Quality - Bits 0-1: MODLAND_QA - 0: VI produced, good quality - 1: VI produced, but check other QA - 2: Pixel produced, but probably cloudy - 3: Pixel not produced due to other reason than clouds - Bits 2-5: VI Usefulness, higher values are worse. - 0: Highest Quality - 1: Lower quality - 2: Decreasing quality - 3: Decreasing quality - 4: Decreasing quality - 5: Decreasing quality - 6: Decreasing quality - 7: Decreasing quality - 8: Decreasing quality - 9: Decreasing quality - 10: Decreasing quality - 11: Decreasing quality - 12: Worst quality - 13: Quality so low that it is not useful - 14: L1B data faulty - 15: Not useful for any reason/not processed - Bits 6-7: Aerosol quantity - 0: Climatology - 1: Low - 2: Average - 3: High - Bit 8: Adjacent cloud detected - 0: No - 1: Yes - Bit 9: Adjacent BRDF correction performed - 0: No - 1: Yes - Bit 10: Mixed clouds - 0: No - 1: Yes - Bits 11-13: Land/Water Flag - 0: land \\& desert - 1: land no desert - 2: inland water - 3: sea_water - 5: coastal - Bit 14: Possible snow/ice - 0: No - 1: Yes - Bit 15: Possible shadow - 0: No - 1: Yes ||||||||||||||||||||||||||||||||||||||||||||||||||||||||||||||||||||||||||||||||||||||||||||||||||||\n| `red_reflectance` | | meters | 600-680nm | Red band reflectance |\n| `green_reflectance` | | meters | 545-656nm | Green band reflectance |\n| `blue_reflectance` | | meters | 478-498nm | Blue band reflectance |\n| `composite_day_of_the_year` | d | meters | None | Julian day of year |\n| `pixel_reliability` | | meters | None | Pixel usefulness using a simple rank class |\n| `relative_azimuth_angle` | deg | meters | None | Relative azimuth angle for each pixel |\n| `sun_zenith_angle` | deg | meters | None | Sun zenith angle for each pixel |\n| `view_zenith_angle` | deg | meters | None | View zenith angle for each pixel |\n\n**pixel_reliability Class Table**\n\n| Value | Color | Description |\n|-------|-------|-----------------------------|\n| 0 | None | Excellent |\n| 1 | None | Good |\n| 2 | None | Acceptable |\n| 3 | None | Marginal |\n| 4 | None | Pass |\n| 5 | None | Questionable |\n| 6 | None | Poor |\n| 7 | None | Cloud Shadow |\n| 8 | None | Snow/Ice |\n| 9 | None | Cloud |\n| 10 | None | Estimated |\n| 11 | None | LTAVG (taken from database) |\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/VNP13A1.002\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/VNP13A1')\n .filter(ee.Filter.date('2017-05-01', '2017-06-30'));\nvar rgb = dataset.select(['EVI']);\nvar rgbVis = {\n min: 0.0,\n max: 1.0,\n palette: ['000000', '004400', '008800', '00bb00', '00ff00'],\n};\nMap.setCenter(17.93, 7.71, 6);\nMap.addLayer(rgb, rgbVis, 'RGB');\n```\n[Open in Code Editor](https://code.earthengine.google.com/?scriptPath=Examples:Datasets/NASA/NASA_VIIRS_002_VNP13A1) \n[VNP13A1.002: VIIRS Vegetation Indices 16-Day 500m](/earth-engine/datasets/catalog/NASA_VIIRS_002_VNP13A1) \nThe Suomi National Polar-Orbiting Partnership (S-NPP) NASA Visible Infrared Imaging Radiometer Suite (VIIRS) Vegetation Indices (VNP13A1) data product provides vegetation indices by a process of selecting the best available pixel over a 16-day acquisition period at 500 meter resolution. The VNP13 data products are designed after the Moderate Resolution Imaging ... \nNASA/VIIRS/002/VNP13A1, 16-day,evi,nasa,ndvi,noaa,npp,vegetation,vegetation-indices,viirs \n2012-01-17T00:00:00Z/2025-08-05T00:00:00Z \n-90 -180 90 180 \nGoogle Earth Engine \nhttps://developers.google.com/earth-engine/datasets\n\n- [https://doi.org/10.5067/VIIRS/VNP13A1.002](https://doi.org/https://doi.org/10.5067/VIIRS/VNP13A1.002)\n- [https://doi.org/10.5067/VIIRS/VNP13A1.002](https://doi.org/https://developers.google.com/earth-engine/datasets/catalog/NASA_VIIRS_002_VNP13A1)"]]
