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Full catalog/MYD13Q1
MYD13Q1·v061·dataset

How green the vegetation is, NDVI (Aqua, 250 m)

MODIS/Aqua Vegetation Indices 16-Day L3 Global 250m SIN Grid V061
biosphere NASA LPCLOUD Level 3 active HDF-EOS2
In plain English

What it measures. How green and healthy plants are across the land, summarized as vegetation greenness indices (NDVI and the related EVI) at 250-meter detail. Higher values mean more lush, actively growing vegetation.

How it's made. Derived from the MODIS instrument on NASA's Aqua satellite; over each 16-day window the software picks the clearest, cloud-free view of each spot and computes the greenness from the red and near-infrared light reflected by the surface.

How & where you'd use it. Used to monitor crop health, droughts, deforestation, and seasonal cycles of vegetation, and to compare today's greenery against decades of past records.

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 (MYD13Q1) Version 6.1 data are generated every 16 days at 250 meter (m) spatial resolution as a Level 3 product. The MYD13Q1 product provides 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 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. Along with the vegetation layers and the two quality layers, the HDF file will have MODIS 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

myd13q1_access.py
import earthaccess
earthaccess.login(strategy="netrc")          # free Earthdata Login

results = earthaccess.search_data(
    short_name="MYD13Q1",
    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.