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Google Earth Engine ——LANDSAT 7归一化植被指数NDVI数据集

These Landsat 7 composites are made from Level L1T orthorectified scenes, using the computed top-of-atmosphere (TOA) reflectance. See ​​Chander et al. (2009)​​ for details on the TOA computation.

As of May 1, 2017, the USGS is no longer producing Pre-Collection Landsat, and therefore this collection is complete. Please switch to a Collection 1-based dataset. See ​​this documentation page​​ for more information.

The Normalized Difference Vegetation Index is generated from the Near-IR and Red bands of each scene as (NIR - Red) / (NIR + Red), and ranges in value from -1.0 to 1.0.

These composites are created from all the scenes in each 32-day period beginning from the first day of the year and continuing to the 352nd day of the year. The last composite of the year, beginning on day 353, will overlap the first composite of the following year by 20 days. All the images from each 32-day period are included in the composite, with the most recent pixel as the composite value.

这些Landsat 7的合成物是由L1T级正射场景制作的,使用计算的大气层顶部(TOA)反射率。关于TOA计算的细节,见Chander等人(2009)。

从2017年5月1日起,美国地质调查局不再生产预收集的Landsat,因此这个收集已经完成。请切换到基于集合1的数据集。更多信息请参见本文档页面。

归一化植被指数由每个场景的近红外和红色波段生成,为(近红外-红色)/(近红外+红色),数值范围为-1.0至1.0。

这些合成物是从一年中的第一天开始,一直到一年中的第352天的每个32天期间的所有场景中创建的。这一年的最后一次合成,从第353天开始,将与下一年的第一次合成重叠20天。每个32天期间的所有图像都包括在合成中,以最近的像素作为合成值。

Dataset Availability

- 2017-05-09T00:00:00

Dataset Provider

​​USGS​​

Collection Snippet

​ee.ImageCollection("LANDSAT/LE7_L1T_32DAY_NDVI")​

Bands Table

Name Description Min* Max* Resolution
NDVI Normalized Difference Vegetation Index -1 1 30 meters

* = Values are estimated

使用说明:

Landsat datasets are federally created data and therefore reside in the public domain and may be used, transferred, or reproduced without copyright restriction.

Acknowledgement or credit of the USGS as data source should be provided by including a line of text citation such as the example shown below.

(Product, Image, Photograph, or Dataset Name) courtesy of the U.S. Geological Survey

Example: Landsat-7 image courtesy of the U.S. Geological Survey

See the ​​USGS Visual Identity System Guidance​​ for further details on proper citation and acknowledgement of USGS products.

Landsat数据集是联邦创建的数据,因此属于公共领域,可以在没有版权限制的情况下使用、转让或复制。

对美国地质调查局作为数据来源的确认或信用,应通过包括一行文字引用来提供,如下面的例子。

(产品、图像、照片或数据集名称)由美国地质调查局提供。

例子。Landsat-7图像由美国地质调查局提供

var dataset = ee.ImageCollection('LANDSAT/LE07/C01/T1_ANNUAL_NDVI')
                  .filterDate('1999-01-01', '2002-12-31');
var colorized = dataset.select('NDVI');
var colorizedVis = {
  min: 0.0,
  max: 1.0,
  palette: [
    'FFFFFF', 'CE7E45', 'DF923D', 'F1B555', 'FCD163', '99B718', '74A901',
    '66A000', '529400', '3E8601', '207401', '056201', '004C00', '023B01',
    '012E01', '011D01', '011301'
  ],
};
Map.setCenter(6.746, 46.529, 6);
Map.addLayer(colorized, colorizedVis, 'Colorized');      
var dataset = ee.ImageCollection('LANDSAT/LE07/C01/T1_8DAY_NDVI')
                  .filterDate('1999-01-01', '2002-12-31');
var colorized = dataset.select('NDVI');
var colorizedVis = {
  min: 0.0,
  max: 1.0,
  palette: [
    'FFFFFF', 'CE7E45', 'DF923D', 'F1B555', 'FCD163', '99B718', '74A901',
    '66A000', '529400', '3E8601', '207401', '056201', '004C00', '023B01',
    '012E01', '011D01', '011301'
  ],
};
Map.setCenter(6.746, 46.529, 6);
Map.addLayer(colorized, colorizedVis, 'Colorized');      
var dataset = ee.ImageCollection('LANDSAT/LE07/C01/T1_32DAY_NDVI')
                  .filterDate('1999-01-01', '2002-12-31');
var colorized = dataset.select('NDVI');
var colorizedVis = {
  min: 0.0,
  max: 1.0,
  palette: [
    'FFFFFF', 'CE7E45', 'DF923D', 'F1B555', 'FCD163', '99B718', '74A901',
    '66A000', '529400', '3E8601', '207401', '056201', '004C00', '023B01',
    '012E01', '011D01', '011301'
  ],
};
Map.setCenter(6.746, 46.529, 6);
Map.addLayer(colorized, colorizedVis, 'Colorized');      

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