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Full catalog/MOD09Q1
MOD09Q1·v061·dataset

True surface color, best-of-week (Terra, 8-day, 250 m)

MODIS/Terra Surface Reflectance 8-Day L3 Global 250m SIN Grid V061
land NASA LPCLOUD Level 3 active HDF-EOS2
In plain English

What it measures. This provides the true reflected color of the land in two bands (red and near-infrared) at a finer 250-meter detail, corrected for the atmosphere. Each pixel is the clearest view selected from an 8-day window.

How it's made. Derived from the MODIS instrument on NASA's Terra satellite, atmospherically corrected and composited to keep the least-cloudy observation over each 8-day period.

How & where you'd use it. Good for tracking vegetation greenness and land change at finer detail than the 500-meter version, useful for crops, forests and seasonal monitoring.

What's measured

LAND SURFACE › SURFACE RADIATIVE PROPERTIES › REFLECTANCE

Coverage & cadence

  • Time span2000-02-18 → ongoing
  • Measured byTerra (MODIS)
  • Processing levelLevel 3
  • Spatial extent-180, -90, 180, 90
  • FormatsHDF-EOS2
  • StatusACTIVE

What you can do with it

  • Track deforestation, fire scars and land-cover change
  • Monitor crop and vegetation health (NDVI/EVI)
  • Map how built-up vs. green an area is over time
Official description

The MOD09Q1 Version 6.1 product provides an estimate of the surface spectral reflectance of Terra Moderate Resolution Imaging Spectroradiometer (MODIS) Bands 1 and 2, corrected for atmospheric conditions such as gasses, aerosols, and Rayleigh scattering. Provided along with the 250 meter (m) surface reflectance bands are two quality layers. For each pixel, a value is selected from all the acquisitions within the 8-day composite period. The criteria for the pixel choice include cloud and solar zenith. When several acquisitions meet the criteria the pixel with the minimum channel 3 (blue) value is used. 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=Terra&as=61).

Get the data

mod09q1_access.py
import earthaccess
earthaccess.login(strategy="netrc")          # free Earthdata Login

results = earthaccess.search_data(
    short_name="MOD09Q1",
    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.