Create a Time-series to Display NDVI Mean Day of Year for Multiple Years using MODIS Data

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)

In this tutorial we will be using MOD13Q1.006 Terra Vegetation Indices 16-Day Global 250m data to create a time-series. Study area is (-58.911, -26.765) in South America.

Study Area: A geometric point (-58.911, -26.765) in South America

This data already has NDVI and EVI bands and we will simply select NDVI band. The MOD13Q1 V6 product provides a Vegetation Index (VI) value at a per pixel basis. There are two primary vegetation layers. The first is the Normalized Difference Vegetation Index (NDVI) which is referred to as the continuity index to the existing National Oceanic and Atmospheric Administration-Advanced Very High Resolution Radiometer (NOAA-AVHRR) derived NDVI. The second vegetation layer is the Enhanced Vegetation Index (EVI) that minimizes canopy background variations and maintains sensitivity over dense vegetation conditions. The EVI also uses the blue band to remove residual atmosphere contamination caused by smoke and sub-pixel thin cloud clouds. The MODIS NDVI and EVI products are computed from atmospherically corrected bi-directional surface reflectances that have been masked for water, clouds, heavy aerosols, and cloud shadows.

More information about the data is found here:

var geometry = ee.Geometry.Point(-58.911, -26.765);
var FirmaNDVI = ee.ImageCollection('MODIS/006/MOD13Q1')
.filterDate('2015-01-01', '2018-12-31')

print('MODIS Annual NDVI Chart', ui.Chart.image.doySeriesByYear(FirmaNDVI, 'NDVI',geometry, ee.Reducer.mean(), 231.65635826395828 ))

var ndviParams = {min: 1000, max: 10000, palette: ['red', 'white', 'green']};

Map.addLayer(FirmaNDVI, ndviParams, "NDVI");
NDVI mean day of year in multiple years

Return to GEE NDVI Page Return to GEE Homepage

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