Google Earth Engine ——MODIS Terra/Aqua Daily归一化差异水指数（NDWI）

The Normalized Difference Water Index (NDWI) is sensitive to changes in liquid water content of vegetation canopies. It is derived from the Near-IR band and a second IR band, ≈1.24μm when available and the nearest available IR band otherwise. It ranges in value from -1.0 to 1.0. See ​​Gao (1996)​​ for details. This product is generated from the MODIS/MOD09GA surface reflectance composites.

归一化差异水指数（NDWI）对植被冠层的液态水含量变化很敏感。它是由近红外波段和第二个红外波段得出的，如果有的话，≈1.24μm，否则就是最近的红外波段。它的数值范围在-1.0到1.0之间。详见Gao（1996）。该产品由MODIS/MOD09GA表面反射率合成物生成。

Dataset Availability

2000-02-24T00:00:00 - 2017-03-30T00:00:00

Dataset Provider

​​Google​​

Collection Snippet

​​ee.ImageCollection("MODIS/MOD09GA_NDWI")​​

Bands Table

使用说明：

MODIS data and products acquired through the LP DAAC have no restrictions on subsequent use, sale, or redistribution.

代码：

var dataset = ee.ImageCollection('MODIS/MCD43A4_006_NDWI')
                  .filter(ee.Filter.date('2018-04-01', '2018-06-01'));
var colorized = dataset.select('NDWI');
var colorizedVis = {
  min: 0.0,
  max: 1.0,
  palette: ['0000ff', '00ffff', 'ffff00', 'ff0000', 'ffffff'],
};
Map.setCenter(-7.03125, 31.0529339857, 2);
Map.addLayer(colorized, colorizedVis, 'Colorized');