O mapa global de floresta/não floresta (FNF) é gerado classificando a imagem SAR (coeficiente de retroespalhamento) no mosaico global de 25 m de resolução PALSAR-2/PALSAR SAR para que pixels de retroespalhamento forte e baixo sejam atribuídos como "floresta" e "não floresta", respectivamente. Aqui, "floresta" é definida como a floresta natural com área maior que 0,5 ha e cobertura florestal acima de 10%. Essa definição é a mesma da Organização das Nações Unidas para Alimentação e Agricultura (FAO). Como o radar de retroespalhamento da floresta depende da região (zona climática), a classificação de floresta/não floresta é feita usando um limite de retroespalhamento dependente da região. A acurácia da classificação é verificada usando fotos in situ e imagens de satélite ópticas de alta resolução.
Os valores de retroespalhamento podem variar significativamente de um caminho para outro em áreas florestais de alta latitude. Isso ocorre devido à mudança na intensidade de retroespalhamento causada pelo congelamento das árvores no inverno.
Isso pode afetar a classificação de floresta/não floresta.
Bandas
Tamanho do pixel 25 metros
Bandas
Nome
Mín.
Máx.
Tamanho do pixel
Descrição
fnf
1
4
metros
Classificação de cobertura de terra florestal/não florestal
Tabela de classes fnf
Valor
Cor
Descrição
1
#00b200
Floresta densa
2
#83ef62
Floresta não densa
3
#ffff99
Não floresta
4
#0000ff
Água
Termos de Uso
Termos de Uso
A JAXA mantém a propriedade do conjunto de dados e não garante nenhum problema causado ou possivelmente causado pelo uso dos conjuntos de dados.
Qualquer pessoa que queira publicar resultados usando os conjuntos de dados precisa reconhecer claramente a propriedade dos dados na publicação.
Citações
Citações:
Masanobu Shimada, Takuya Itoh, Takeshi Motooka, Manabu Watanabe, Shiraishi Tomohiro, Rajesh Thapa e Richard Lucas, "New Global Forest/Non-forest Maps from ALOS PALSAR Data (2007-2010)", Remote Sensing of Environment, 155, pp. 13-31, dezembro de 2014. doi:10.1016/j.rse.2014.04.014.
O mapa global de floresta/não floresta (FNF) é gerado classificando a imagem de SAR (coeficiente de retroespalhamento) no mosaico global de 25 m de resolução PALSAR-2/PALSAR SAR para que pixels de retroespalhamento forte e baixo sejam atribuídos como "floresta" e "não floresta", respectivamente. Aqui, "floresta" é definida como a floresta natural com área maior que 0,5…
[null,null,[],[[["\u003cp\u003eThe JAXA/ALOS/PALSAR/YEARLY/FNF4 dataset provides a global forest/non-forest map at 25-meter resolution, classifying areas as Dense Forest, Non-dense Forest, Non-Forest, and Water.\u003c/p\u003e\n"],["\u003cp\u003eThis dataset utilizes PALSAR-2/PALSAR SAR mosaic data from 2017 to 2021, applying a region-dependent threshold of backscatter to classify forest and non-forest areas.\u003c/p\u003e\n"],["\u003cp\u003eThe classification aligns with the Food and Agriculture Organization (FAO) definition of forest as natural forest with an area larger than 0.5 ha and forest cover over 10%.\u003c/p\u003e\n"],["\u003cp\u003eUsers should be aware that backscatter values can vary significantly over high latitude forest areas due to seasonal changes, potentially impacting classification accuracy.\u003c/p\u003e\n"],["\u003cp\u003eJAXA retains ownership of the dataset and encourages users to acknowledge the data source in any publications resulting from its use.\u003c/p\u003e\n"]]],[],null,["# Global 4-class PALSAR-2/PALSAR Forest/Non-Forest Map\n\nDataset Availability\n: 2017-01-01T00:00:00Z--2021-01-01T00:00:00Z\n\nDataset Provider\n:\n\n\n [JAXA EORC](https://www.eorc.jaxa.jp/ALOS/en/dataset/fnf_e.htm)\n\nTags\n:\n[alos](/earth-engine/datasets/tags/alos) [alos2](/earth-engine/datasets/tags/alos2) [classification](/earth-engine/datasets/tags/classification) [eroc](/earth-engine/datasets/tags/eroc) [forest](/earth-engine/datasets/tags/forest) [forest-biomass](/earth-engine/datasets/tags/forest-biomass) [jaxa](/earth-engine/datasets/tags/jaxa) [landcover](/earth-engine/datasets/tags/landcover) [palsar](/earth-engine/datasets/tags/palsar) [palsar2](/earth-engine/datasets/tags/palsar2) [sar](/earth-engine/datasets/tags/sar) \n\n#### Description\n\nThe global forest/non-forest map (FNF) is generated by\nclassifying the SAR image (backscattering coefficient) in the\nglobal 25m resolution PALSAR-2/PALSAR SAR mosaic so that strong and\nlow backscatter pixels are assigned as \"forest\" and \"non-forest\",\nrespectively. Here, \"forest\" is defined as the natural forest\nwith the area larger than 0.5 ha and forest cover over 10%. This\ndefinition is the same as the Food and Agriculture Organization\n(FAO) definition. Since the radar backscatter from the forest\ndepends on the region (climate zone), the classification of\nForest/Non-Forest is conducted by using a region-dependent\nthreshold of backscatter. The classification accuracy is\nchecked by using in-situ photos and high-resolution optical\nsatellite images.\n\nDetailed information:\n\n- [2017 - 2020](https://www.eorc.jaxa.jp/ALOS/en/dataset/pdf/DatasetDescription_PALSAR2_FNF_v200a.pdf)\n\nAttention:\n\n- Backscatter values may vary significantly from path to path over high latitude forest areas. This is due to the change of backscattering intensity caused by freezing trees in winter. Please note that this may affect the classification of forest/non-forest.\n\n### Bands\n\n\n**Pixel Size**\n\n25 meters\n\n**Bands**\n\n| Name | Min | Max | Pixel Size | Description |\n|-------|-----|-----|------------|--------------------------------------------|\n| `fnf` | 1 | 4 | meters | Forest/Non-Forest landcover classification |\n\n**fnf Class Table**\n\n| Value | Color | Description |\n|-------|---------|------------------|\n| 1 | #00b200 | Dense Forest |\n| 2 | #83ef62 | Non-dense Forest |\n| 3 | #ffff99 | Non-Forest |\n| 4 | #0000ff | Water |\n\n### Terms of Use\n\n**Terms of Use**\n\nJAXA retains ownership of the dataset and cannot guarantee\nany problem caused by or possibly caused by using the datasets.\nAnyone wishing to publish any results using the datasets should\nclearly acknowledge the ownership of the data in the publication.\n\n### Citations\n\nCitations:\n\n- Masanobu Shimada, Takuya Itoh, Takeshi Motooka, Manabu Watanabe,\n Shiraishi Tomohiro, Rajesh Thapa, and Richard Lucas, \"New Global\n Forest/Non-forest Maps from ALOS PALSAR Data (2007-2010)\", Remote Sensing\n of Environment, 155, pp. 13-31, December 2014.\n [doi:10.1016/j.rse.2014.04.014.](https://doi.org/10.1016/j.rse.2014.04.014)\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('JAXA/ALOS/PALSAR/YEARLY/FNF4')\n .filterDate('2018-01-01', '2018-12-31');\nvar forestNonForest = dataset.select('fnf');\nvar forestNonForestVis = {\n min: 1,\n max: 4,\n palette: ['00b200','83ef62','ffff99','0000ff'],\n};\nMap.setCenter(136.85, 37.37, 4);\nMap.addLayer(forestNonForest, forestNonForestVis, 'Forest/Non-Forest');\n```\n[Open in Code Editor](https://code.earthengine.google.com/?scriptPath=Examples:Datasets/JAXA/JAXA_ALOS_PALSAR_YEARLY_FNF4) \n[Global 4-class PALSAR-2/PALSAR Forest/Non-Forest Map](/earth-engine/datasets/catalog/JAXA_ALOS_PALSAR_YEARLY_FNF4) \nThe global forest/non-forest map (FNF) is generated by classifying the SAR image (backscattering coefficient) in the global 25m resolution PALSAR-2/PALSAR SAR mosaic so that strong and low backscatter pixels are assigned as \"forest\" and \"non-forest\", respectively. Here, \"forest\" is defined as the natural forest with the area larger than 0.5 ... \nJAXA/ALOS/PALSAR/YEARLY/FNF4, alos,alos2,classification,eroc,forest,forest-biomass,jaxa,landcover,palsar,palsar2,sar \n2017-01-01T00:00:00Z/2021-01-01T00:00:00Z \n-90 -180 90 180 \nGoogle Earth Engine \nhttps://developers.google.com/earth-engine/datasets\n\n- [](https://doi.org/https://www.eorc.jaxa.jp/ALOS/en/dataset/fnf_e.htm)\n- [](https://doi.org/https://developers.google.com/earth-engine/datasets/catalog/JAXA_ALOS_PALSAR_YEARLY_FNF4)"]]
