Use Normalized Difference Vegetation Index (NDVI) to Determine Bare-Land

The Normalized Difference Vegetation Index (NDVI) is a simple graphical indicator that can be used to analyze remote sensing measurements, typically, but not necessarily, from a space platform, and assess whether the target being observed contains live green vegetation or not.

The NDVI is calculated from these individual measurements as follows:

NDVI= (NIR-Red) \ (NIR+Red)

The following code is available in “Relational, conditional and Boolean operations” page of Google Earth Engine Developer page. I found it interesting and worth-sharing so I copied the code as it is here. If you want to learn more about it, please go here:

//source: https://developers.google.com/earth-engine/image_relational 

// Load a Landsat 8 image.
var image = ee.Image('LANDSAT/LC08/C01/T1_TOA/LC08_044034_20140318');

// Create NDVI and NDWI spectral indices.
var ndvi = image.normalizedDifference(['B5', 'B4']);
var ndwi = image.normalizedDifference(['B3', 'B5']);

// Create a binary layer using logical operations.
var bare = ndvi.lt(0.2).and(ndwi.lt(0));

// Mask and display the binary layer.
Map.setCenter(-122.3578, 37.7726, 12);
Map.setOptions('satellite');
Map.addLayer(bare.updateMask(bare), {}, 'bare');
relational_sf
Low NDVI and low NDWI (white) from Landsat 8, San Francisco, California, USA. (Source: Google Earth Engine)

Return to GEE NDVI Page Return to GEE Homepage

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