VNP13A1: VIIRS Vegetation Indices 16-Day 500m

NOAA/VIIRS/001/VNP13A1
Dataset Availability
2012-01-17T00:00:00Z–2024-03-05T00:00:00Z
Dataset Provider
Earth Engine Snippet
ee.ImageCollection("NOAA/VIIRS/001/VNP13A1")
Tags
16-day evi nasa ndvi noaa npp vegetation viirs
vnp13a1

Description

The Suomi National Polar-Orbiting Partnership (S-NPP) NASA Visible Infrared Imaging Radiometer Suite (VIIRS) Vegetation Indices (VNP13A1) data product provides vegetation indices by a process of selecting the best available pixel over a 16-day acquisition period at 500 meter resolution. The VNP13 data products are designed after the Moderate Resolution Imaging Spectroradiometer (MODIS) Terra and Aqua Vegetation Indices product suite to promote the continuity of the Earth Observation System (EOS) mission.

The VNP13 algorithm process produces three vegetation indices: (1) Normalized Difference Vegetation Index (NDVI), (2) the Enhanced Vegetation Index (EVI), and (3) Enhanced Vegetation Index-2 (EVI2). (1) NDVI is one of the longest continual remotely sensed time series observations, using both the red and near-infrared (NIR) bands. (2) EVI is a slightly different vegetation index that is more sensitive to canopy cover, while NDVI is more sensitive to chlorophyll. (3) EVI2 is a reformation of the standard 3-band EVI, using the red band and NIR band. This reformation addresses arising issues when comparing VIIRS EVI to other EVI models that do not include a blue band. EVI2 will eventually become the standard EVI.

Along with the three Vegetation Indices layers, this product also includes layers for near-infrared (NIR) reflectance; three shortwave infrared (SWIR) reflectance-red, blue, and green reflectance; composite day of year; pixel reliability; view and sun angles, and a quality layer.

For additional information, visit the VIIRS Land Product Quality Assessment website and see the User Guide.

Documentation:

Bands

Resolution
500 meters

Bands

Name Units Scale Wavelength Description
EVI 0.0001

3 band Enhanced Vegetation Index

EVI2 0.0001

2 band Enhanced Vegetation Index

NDVI 0.0001

Normalized Difference Vegetation Index

NIR_reflectance 846-885nm

Near-infrared Radiation reflectance

SWIR1_reflectance 1230-1250nm

Shortwave Infrared Radiation reflectance

SWIR2_reflectance 1580-1640nm

Shortwave Infrared Radiation reflectance

SWIR3_reflectance 2225-2275nm

Shortwave Infrared Radiation reflectance

VI_Quality

Quality Assessment (QA) bit-field.

red_reflectance 600-680nm

Red band reflectance

green_reflectance 545-656nm

Green band reflectance

blue_reflectance 478-498nm

Blue band reflectance

composite_day_of_the_year d

Julian day of year

pixel_reliability

Pixel usefulness using a simple rank class

relative_azimuth_angle deg

Relative azimuth angle for each pixel

sun_zenith_angle deg

Sun zenith angle for each pixel

view_zenith_angle deg

View zenith angle for each pixel

pixel_reliability Class Table

Value Color Description
0 Excellent
1 Good
2 Acceptable
3 Marginal
4 Pass
5 Questionable
6 Poor
7 Cloud Shadow
8 Snow/Ice
9 Cloud
10 Estimated
11 LTAVG (taken from database)

Terms of Use

Terms of Use

LP DAAC NASA data are freely accessible; however, when an author publishes these data or works based on the data, it is requested that the author cite the datasets within the text of the publication and include a reference to them in the reference list.

Citations

Citations:

DOIs

Explore with Earth Engine

Code Editor (JavaScript)

var dataset = ee.ImageCollection('NOAA/VIIRS/001/VNP13A1');
var mean_evi_january_2018 = dataset
    .filterDate('2018-01-01', '2018-01-31')
    .select('EVI')
    .mean();
var evi_vis = {
  min: 0,
  max: 10000,
  palette: ['000000', '004400', '008800', '00bb00', '00ff00'],
};
Map.setCenter(95.571, 27.808, 8);
Map.addLayer(mean_evi_january_2018, evi_vis, 'Mean EVI January 2018');
Open in Code Editor