Dataset cahaya malam VIIRS global tahunan adalah deret waktu yang dihasilkan dari
petak radiasi rata-rata bebas awan bulanan untuk tahun 2022. Data untuk tahun-tahun sebelumnya tersedia di set data NOAA/VIIRS/DNB/ANNUAL_V21.
Langkah pemfilteran awal menghapus piksel yang terkena sinar matahari, sinar bulan, dan awan,
sehingga menghasilkan komposit kasar yang berisi cahaya, api, aurora, dan
latar belakang. Komposit tahunan kasar dibuat dalam inkremen bulanan dan
kemudian digabungkan untuk membentuk komposit tahunan kasar.
Langkah-langkah berikutnya menggunakan median radiasi dua belas bulan untuk menghapus pencilan radiasi tinggi dan rendah, memfilter sebagian besar kebakaran, dan mengisolasi latar belakang. Area latar belakang diatur ke nol menggunakan rentang data (DR) yang dihitung dari sel petak 3x3. Nilai minimum DR untuk latar belakang diindeks ke tingkat tutupan awan, dengan nilai minimum DR yang lebih tinggi di area yang memiliki jumlah cakupan bebas awan yang rendah.
Band
Ukuran Piksel 463,83 meter
Band
Nama
Unit
Ukuran Piksel
Deskripsi
average
nanoWatt/sr/cm^2
meter
Nilai radiasi DNB rata-rata.
average_masked
nanoWatt/sr/cm^2
meter
Nilai radiasi DNB tersamar rata-rata
cf_cvg
meter
Cakupan bebas awan; jumlah total pengamatan yang
masuk ke setiap piksel. Rentang ini dapat digunakan untuk mengidentifikasi area dengan jumlah pengamatan yang rendah sehingga kualitasnya berkurang.
cvg
meter
Jumlah total pengamatan tanpa sinar matahari dan sinar bulan.
maximum
nanoWatt/sr/cm^2
meter
Nilai radiasi DNB maksimum.
median
nanoWatt/sr/cm^2
meter
Nilai radiasi DNB median
median_masked
nanoWatt/sr/cm^2
meter
Nilai radiasi DNB yang disamarkan mediannya.
minimum
nanoWatt/sr/cm^2
meter
Nilai radiasi DNB minimum
Persyaratan Penggunaan
Persyaratan Penggunaan
Data, informasi, dan produk Colorado School of Mines, terlepas dari metode pengirimannya, tidak tunduk pada hak cipta dan tidak memiliki batasan pada penggunaan selanjutnya oleh publik. Setelah diperoleh, data tersebut dapat digunakan untuk tujuan yang sah. Data di atas berada dalam domain publik dan disediakan tanpa batasan penggunaan dan distribusi.
Kutipan
Kutipan:
Elvidge, C.D, Zhizhin, M., Ghosh T., Hsu FC, Taneja J. Deret waktu tahunan
lampu malam VIIRS global yang berasal dari rata-rata bulanan:2012 hingga 2019.
Remote Sensing 2021, 13(5), hlm.922, doi:10.3390/rs13050922
doi:10.3390/rs13050922
Dataset cahaya malam VIIRS global tahunan adalah deret waktu yang dihasilkan dari rata-rata grid radiasi bulanan bebas awan untuk tahun 2022. Data untuk tahun-tahun sebelumnya tersedia di set data NOAA/VIIRS/DNB/ANNUAL_V21. Langkah pemfilteran awal menghapus piksel yang terkena sinar matahari, sinar bulan, dan awan, sehingga menghasilkan komposit kasar yang berisi cahaya, api, aurora, dan latar belakang. …
[null,null,[],[[["\u003cp\u003eThe NOAA/VIIRS/DNB/ANNUAL_V22 dataset provides annual global VIIRS nighttime lights data from monthly cloud-free average radiance grids for 2022.\u003c/p\u003e\n"],["\u003cp\u003eThe dataset includes bands representing average, masked, cloud-free coverages, total observations, maximum, median, and minimum DNB radiance values.\u003c/p\u003e\n"],["\u003cp\u003eData is freely available for public use with no restrictions, provided by the Colorado School of Mines.\u003c/p\u003e\n"],["\u003cp\u003ePrevious years' data (before 2022) can be accessed through the NOAA/VIIRS/DNB/ANNUAL_V21 dataset.\u003c/p\u003e\n"],["\u003cp\u003eThe dataset utilizes filtering to remove sunlit, moonlit, and cloudy pixels, minimizing the influence of fires and aurorae on light measurements.\u003c/p\u003e\n"]]],["The annual VIIRS nighttime lights dataset, provided by the Colorado School of Mines, spans from April 1, 2012, to January 1, 2023. The dataset is derived from monthly, cloud-free radiance grids. Data processing involves filtering out sunlit, moonlit, and cloudy pixels, followed by median radiance analysis to eliminate outliers like fires. Background areas are then zeroed out. The dataset includes bands like 'average,' 'maximum,' 'minimum,' and 'median' radiance, along with cloud-free coverage data, it's available in the Earth Engine platform.\n"],null,["# VIIRS Nighttime Day/Night Annual Band Composites V2.2\n\nDataset Availability\n: 2012-04-01T00:00:00Z--2024-01-01T00:00:00Z\n\nDataset Provider\n:\n\n\n [Earth Observation Group, Payne Institute for Public Policy, Colorado School of Mines](https://eogdata.mines.edu/products/vnl/#annual_v2)\n\nCadence\n: 1 Year\n\nTags\n:\n[annual](/earth-engine/datasets/tags/annual) [dnb](/earth-engine/datasets/tags/dnb) [eog](/earth-engine/datasets/tags/eog) [lights](/earth-engine/datasets/tags/lights) [nighttime](/earth-engine/datasets/tags/nighttime) [noaa](/earth-engine/datasets/tags/noaa) [population](/earth-engine/datasets/tags/population) [viirs](/earth-engine/datasets/tags/viirs) [visible](/earth-engine/datasets/tags/visible) \n\n#### Description\n\nAnnual global VIIRS nighttime lights dataset is a time series produced from\nmonthly cloud-free average radiance grids for 2022. Data for earlier\nyears are available in the\n[NOAA/VIIRS/DNB/ANNUAL_V21](/earth-engine/datasets/catalog/NOAA_VIIRS_DNB_ANNUAL_V21) dataset.\n\nAn initial filtering step removed sunlit, moonlit and cloudy pixels,\nleading to rough composites that contains lights, fires, aurora and\nbackground. The rough annual composites are made on monthly increments and\nthen combined to form rough annual composites.\n\nThe subsequent steps uses the twelve-month median radiance to discard high\nand low radiance outliers, filtering out most fires and isolating the\nbackground. Background areas are zeroed out using the data range (DR)\ncalculated from 3x3 grid cells. The DR threshold for background is indexed\nto cloud-cover levels, with higher DR thresholds in areas having low numbers\nof cloud-free coverages.\n\n### Bands\n\n\n**Pixel Size**\n\n463.83 meters\n\n**Bands**\n\n| Name | Units | Pixel Size | Description |\n|------------------|--------------------|------------|------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------|\n| `average` | nanoWatts/sr/cm\\^2 | meters | Average DNB radiance values. |\n| `average_masked` | nanoWatts/sr/cm\\^2 | meters | Average Masked DNB radiance values |\n| `cf_cvg` | | meters | Cloud-free coverages; the total number of observations that went into each pixel. This band can be used to identify areas with low numbers of observations where the quality is reduced. |\n| `cvg` | | meters | Total number of observations free of sunlight and moonlight. |\n| `maximum` | nanoWatts/sr/cm\\^2 | meters | Maximum DNB radiance values. |\n| `median` | nanoWatts/sr/cm\\^2 | meters | Median DNB radiance values |\n| `median_masked` | nanoWatts/sr/cm\\^2 | meters | Median masked DNB radiance values. |\n| `minimum` | nanoWatts/sr/cm\\^2 | meters | Minimum DNB radiance values |\n\n### Terms of Use\n\n**Terms of Use**\n\nColorado School of Mines data, information, and products,\nregardless of the method of delivery,\nare not subject to copyright and carry no restrictions on their subsequent\nuse by the public. Once obtained, they may be put to any lawful use. The\nforgoing data is in the public domain and is being provided without\nrestriction on use and distribution.\n\n### Citations\n\nCitations:\n\n- Elvidge, C.D, Zhizhin, M., Ghosh T., Hsu FC, Taneja J. Annual time series of\n global VIIRS nighttime lights derived from monthly averages:2012 to 2019.\n Remote Sensing 2021, 13(5), p.922, doi:10.3390/rs13050922\n [doi:10.3390/rs13050922](https://doi.org/10.3390/rs13050922)\n\n### DOIs\n\n- \u003chttps://doi.org/10.3390/rs13050922\u003e\n\n### Explore with Earth Engine\n\n| **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\n### Code Editor (JavaScript)\n\n```javascript\nvar dataset = ee.ImageCollection('NOAA/VIIRS/DNB/ANNUAL_V22')\n .filter(ee.Filter.date('2022-01-01', '2023-01-01'));\n\nvar nighttime = dataset.select('maximum');\nvar nighttimeVis = {min: 0.0, max: 60.0};\nMap.setCenter(-77.1056, 38.8904, 8);\nMap.addLayer(nighttime, nighttimeVis, 'Nighttime');\n```\n[Open in Code Editor](https://code.earthengine.google.com/?scriptPath=Examples:Datasets/NOAA/NOAA_VIIRS_DNB_ANNUAL_V22) \n[VIIRS Nighttime Day/Night Annual Band Composites V2.2](/earth-engine/datasets/catalog/NOAA_VIIRS_DNB_ANNUAL_V22) \nAnnual global VIIRS nighttime lights dataset is a time series produced from monthly cloud-free average radiance grids for 2022. Data for earlier years are available in the NOAA/VIIRS/DNB/ANNUAL_V21 dataset. An initial filtering step removed sunlit, moonlit and cloudy pixels, leading to rough composites that contains lights, fires, aurora and background. ... \nNOAA/VIIRS/DNB/ANNUAL_V22, annual,dnb,eog,lights,nighttime,noaa,population,viirs,visible \n2012-04-01T00:00:00Z/2024-01-01T00:00:00Z \n-65 -180 75 180 \nGoogle Earth Engine \nhttps://developers.google.com/earth-engine/datasets\n\n- [https://doi.org/10.3390/rs13050922](https://doi.org/https://eogdata.mines.edu/products/vnl/#annual_v2)\n- [https://doi.org/10.3390/rs13050922](https://doi.org/https://developers.google.com/earth-engine/datasets/catalog/NOAA_VIIRS_DNB_ANNUAL_V22)"]]
