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Full catalog/MYD13A1
MYD13A1·v061·dataset

How green the land is (Aqua, 16-day, 500 m)

MODIS/Aqua Vegetation Indices 16-Day L3 Global 500m SIN Grid V061
biosphere NASA LPCLOUD Level 3 active HDF-EOS2
In plain English

What it measures. How green and healthy land vegetation is, as two indices (NDVI and EVI) that climb with denser, healthier plants. It also includes the red, near-infrared, blue, and mid-infrared light bands used to compute them.

How it's made. Generated from the MODIS instrument on NASA's Aqua satellite, picking the best clear pixel over each 16-day window at 500-meter resolution.

How & where you'd use it. Used to monitor crops and forests, detect drought stress, and study land cover change and its role in climate and water cycles.

What's measured

BIOSPHERE › VEGETATION › VEGETATION INDEXBIOSPHERE › VEGETATION › VEGETATION INDEX › NORMALIZED DIFFERENCE VEGETATION INDEX (NDVI)BIOSPHERE › VEGETATION › VEGETATION INDEX › ENHANCED VEGETATION INDEX (EVI)

Coverage & cadence

  • Time span2002-07-04 → ongoing
  • Measured byAqua (MODIS)
  • Processing levelLevel 3
  • Spatial extent-180, -90, 180, 90
  • FormatsHDF-EOS2
  • StatusACTIVE

What you can do with it

  • Map vegetation, forests and biomass
  • Monitor ecosystem productivity and carbon
  • Support habitat and biodiversity studies
Official description

The Aqua Moderate Resolution Imaging Spectroradiometer (MODIS) Vegetation Indices 16-Day (MYD13A1) Version 6.1 product provides Vegetation Index (VI) values at a per pixel basis at 500 meter (m) spatial resolution. 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), which has improved sensitivity over high biomass regions. The algorithm for this product chooses the best available pixel value from all the acquisitions from the 16 day period. The criteria used is low clouds, low view angle, and the highest NDVI/EVI value. Provided along with the vegetation layers and two quality assurance (QA) layers are reflectance bands 1 (red), 2 (near-infrared), 3 (blue), and 7 (mid-infrared), as well as four observation layers. Known Issues * For complete information about known issues please refer to the [MODIS/VIIRS Land Quality Assessment website](https://landweb.modaps.eosdis.nasa.gov/knownissue?sensor=MODIS&sat=Aqua&as=61).

Get the data

myd13a1_access.py
import earthaccess
earthaccess.login(strategy="netrc")          # free Earthdata Login

results = earthaccess.search_data(
    short_name="MYD13A1",
    version="061",
    bounding_box=(-122.5, 37.2, -121.8, 37.9),  # your area (W,S,E,N)
    temporal=("2024-01-01", "2024-12-31"),       # your dates
)
files = earthaccess.open(results)   # stream straight from LPCLOUD
Browsing CMR needs no login. Downloading or streaming bytes needs a free Earthdata Login + the earthaccess package.