Terra MODIS 植被连续场 (VCF) 产品是全球地表植被覆盖估计值的亚像素级表示。该指数旨在以基本植被特征的比例连续表示地球陆地表面,提供三种地表覆盖成分的梯度:树木覆盖百分比、非树木覆盖百分比和裸地百分比。VCF 产品可提供连续、定量的地表覆盖信息,并具有更高的空间细节,因此广泛应用于环境建模和监控应用。
VCF 产品每年生成一次,使用 Terra MODIS 250 米和 500 米地表反射率数据的月度合成数据(包括所有七个波段)以及地表温度数据生成。
[null,null,[],[],["The Terra MODIS VCF product, available from 2000-03-05 to 2023-03-06 via NASA LP DAAC, offers yearly global vegetation cover data. It uses 250-meter resolution to estimate percent tree cover, non-tree vegetation, and bare ground. Data is derived from Terra MODIS Land Surface Reflectance. The product includes quality and cloud data indicators. Access to use is through google Earth engine, with JavaScript code examples for visualization.\n"],null,["# MOD44B.061 Terra Vegetation Continuous Fields Yearly Global 250m\n\nDataset Availability\n: 2000-03-05T00:00:00Z--2024-03-05T00:00:00Z\n\nDataset Provider\n:\n\n\n [NASA LP DAAC at the USGS EROS Center](https://doi.org/10.5067/MODIS/MOD44B.006)\n\nCadence\n: 1 Year\n\nTags\n:\n [annual](/earth-engine/datasets/tags/annual) [geophysical](/earth-engine/datasets/tags/geophysical) [global](/earth-engine/datasets/tags/global) [landuse-landcover](/earth-engine/datasets/tags/landuse-landcover) [modis](/earth-engine/datasets/tags/modis) [nasa](/earth-engine/datasets/tags/nasa) [terra](/earth-engine/datasets/tags/terra) [tree-cover](/earth-engine/datasets/tags/tree-cover) [vegetation](/earth-engine/datasets/tags/vegetation) \nmod44b \n\n#### Description\n\nThe Terra MODIS Vegetation Continuous Fields (VCF)\nproduct is a sub-pixel-level representation of surface vegetation\ncover estimates globally. Designed to continuously represent\nEarth's terrestrial surface as a proportion of basic vegetation\ntraits, it provides a gradation of three surface cover components:\npercent tree cover, percent non-tree cover, and percent bare.\nVCF products provide a continuous, quantitative portrayal of\nland surface cover with improved spatial detail, and hence, are\nwidely used in environmental modeling and monitoring applications.\n\nGenerated yearly, the VCF product is produced using monthly\ncomposites of Terra MODIS 250 and 500 meters Land Surface Reflectance\ndata, including all seven bands, and Land Surface Temperature.\n\nDocumentation:\n\n- [User's Guide](https://lpdaac.usgs.gov/documents/1494/MOD44B_User_Guide_V61.pdf)\n\n- [Algorithm Theoretical Basis Document (ATBD)](https://lpdaac.usgs.gov/documents/113/MOD44B_ATBD.pdf)\n\n- [General Documentation](https://lpdaac.usgs.gov/products/mod44bv061/)\n\n### Bands\n\n\n**Pixel Size**\n\n250 meters\n\n**Bands**\n\n| Name | Units | Min | Max | Scale | Pixel Size | Description |\n|------------------------------|-------|-----|-------|-------|------------|---------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------|---|---|---|---|---|---|---|---|---|---|---|---|---|---|---|---|---|---|---|---|---|---|---|---|---|---|---|---|---|---|---|---|---|---|---|---|---|---|---|---|---|---|---|---|---|---|---|---|---|---|---|---|---|---|---|---|---|---|---|---|---|---|---|---|---|---|---|---|---|---|---|---|---|---|---|---|---|---|---|---|---|---|---|---|---|---|---|---|---|---|---|---|---|\n| `Percent_Tree_Cover` | % | 0 | 100 | | meters | Percent of a pixel which is covered by tree canopy |\n| `Percent_NonTree_Vegetation` | % | 0 | 100 | | meters | Percent of a pixel which is covered by non-tree vegetation |\n| `Percent_NonVegetated` | % | 0 | 100 | | meters | Percent of a pixel which is not vegetated |\n| `Quality` | | | | | meters | Describes those inputs that had poor quality (cloudy, high aerosol, cloud shadow, or view zenith \\\u003e45°). Each bit in the field represents 1 out of 8 input surface reflectance files to the model. |\n| Bitmask for Quality - Bit 0: State of input layers DOY 065-097 - 0: Clear - 1: Bad - Bit 1: State of input layers DOY 113-145 - 0: Clear - 1: Bad - Bit 2: State of input layers DOY 161-193 - 0: Clear - 1: Bad - Bit 3: State of input layers DOY 209-241 - 0: Clear - 1: Bad - Bit 4: State of input layers DOY 257-289 - 0: Clear - 1: Bad - Bit 5: State of input layers DOY 305-337 - 0: Clear - 1: Bad - Bit 6: State of input layers DOY 353-017 - 0: Clear - 1: Bad - Bit 7: State of input layers DOY 033-045 - 0: Clear - 1: Bad ||||||||||||||||||||||||||||||||||||||||||||||||||||||||||||||||||||||||||||||||||||||||||||||||||||\n| `Percent_Tree_Cover_SD` | % | 0 | 32767 | 0.01 | meters | Standard deviation (SD) of the 30 models that were used to generate the pixel value in the percent tree cover data layer |\n| `Percent_NonVegetated_SD` | % | 0 | 32767 | 0.01 | meters | Standard deviation (SD) of the 30 models that were used to generate the pixel value in the percent non-vegetated data layer |\n| `Cloud` | | | | | meters | Clarifies the 'Quality' layer to give the user an indication that the 'bad' data refers to cloudy input data. Each bit in the field represents 1 out of 8 input surface reflectance files to the model. |\n| Bitmask for Cloud - Bit 0: State of input layers DOY 065-097 - 0: Clear - 1: Cloudy - Bit 1: State of input layers DOY 113-145 - 0: Clear - 1: Cloudy - Bit 2: State of input layers DOY 161-193 - 0: Clear - 1: Cloudy - Bit 3: State of input layers DOY 209-241 - 0: Clear - 1: Cloudy - Bit 4: State of input layers DOY 257-289 - 0: Clear - 1: Cloudy - Bit 5: State of input layers DOY 305-337 - 0: Clear - 1: Cloudy - Bit 6: State of input layers DOY 353-017 - 0: Clear - 1: Cloudy - Bit 7: State of input layers DOY 033-045 - 0: Clear - 1: Cloudy ||||||||||||||||||||||||||||||||||||||||||||||||||||||||||||||||||||||||||||||||||||||||||||||||||||\n\n### Terms of Use\n\n**Terms of Use**\n\nMODIS data and products acquired through the LP DAAC\nhave no restrictions on subsequent use, sale, or redistribution.\n\n### Citations\n\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\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('MODIS/061/MOD44B')\n .filter(ee.Filter.date('2000-01-01', '2001-01-01'));\n\nvar visualization = {\n bands: ['Percent_Tree_Cover'],\n min: 0,\n max: 100,\n palette: ['bbe029', '0a9501', '074b03']\n};\n\nMap.setCenter(6.746, 46.529, 3);\n\nMap.addLayer(dataset, visualization, 'Percent Tree Cover');\n```\n[Open in Code Editor](https://code.earthengine.google.com/?scriptPath=Examples:Datasets/MODIS/MODIS_061_MOD44B) \n[MOD44B.061 Terra Vegetation Continuous Fields Yearly Global 250m](/earth-engine/datasets/catalog/MODIS_061_MOD44B) \nThe Terra MODIS Vegetation Continuous Fields (VCF) product is a sub-pixel-level representation of surface vegetation cover estimates globally. Designed to continuously represent Earth's terrestrial surface as a proportion of basic vegetation traits, it provides a gradation of three surface cover components: percent tree cover, percent non-tree cover, and percent bare. ... \nMODIS/061/MOD44B, annual,geophysical,global,landuse-landcover,modis,nasa,terra,tree-cover,vegetation \n2000-03-05T00:00:00Z/2024-03-05T00:00:00Z \n-90 -180 90 180 \nGoogle Earth Engine \nhttps://developers.google.com/earth-engine/datasets\n\n- [](https://doi.org/https://doi.org/10.5067/MODIS/MOD44B.006)\n- [](https://doi.org/https://developers.google.com/earth-engine/datasets/catalog/MODIS_061_MOD44B)"]]