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Normalized Difference Moisture Index

Normalized Difference Moisture Index (NDMI) is used to determine vegetation water content. It is calculated as a ratio between the NIR and SWIR values in traditional fashion.

Return to Landsat Surface Reflectance-derived Spectral Indices Overview

 

Landsat Surface Reflectance and Normalized Difference Moisture Index
This image displays a (left) Landsat 8 Surface Reflectance (SR) and (right) the SR-derived Landsat Surface Reflectance Normalized Difference Moisture Index (NDMI).

Landsat Surface Reflectance-derived Normalized Difference Moisture Index (NDMI) are produced from Landsat 4–5 Thematic Mapper (TM), Landsat 7 Enhanced Thematic Mapper Plus (ETM+), and Landsat 8-9* Operational Land Imager (OLI)/Thermal Infrared Sensor (TIRS) Collection 1 and Collection 2 scenes that have been processed to Landsat Level-2 Surface Reflectance products. *Landsat 9 = Collection 2 only 

NDMI is used to determine vegetation water content. It is calculated as a ratio between the NIR and SWIR values in traditional fashion.

(NIR - SWIR) / (NIR + SWIR)

In Landsat 4-7, NDMI = (Band 4 – Band 5) / (Band 4 + Band 5).

In Landsat 8-9, NDMI = (Band 5 – Band 6) / (Band 5 + Band 6).

NDMI is delivered as a single band product specified as shown in the table below.

Landsat Surface Reflectance-derived Normalized Difference Moisture Index (NDMI) Specifications
Attribute Value
Long Name Normalized Difference Moisture Index
Short Name LC8NDMI, LE7NDMI, LT5NDMI, or LT4NDMI
File Name *_sr_ndmi.tif
Data Type Signed 16-bit Integer
Units Spectral Index (Band Ratio)
Valid Range -10,000 — 10,000
Fill Value Collection 2: -19999 Collection 1: -9999
Saturate Value 20,000
Scale Factor *0.0001

Data Access

Landsat Surface Reflectance-derived NDMI are produced on-demand, using the USGS Earth Resources Observation and Science (EROS) Center Science Processing Architecture (ESPA) On Demand Interface

Visit the Landsat Surface Reflectance-derived Spectral Indices page for information on product contraints, citation, and reference information.