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Full catalog/MOD09Q1
MOD09Q1·v006·dataset

True surface color reflectance (Terra, 8-day, 250 m)

MODIS/Terra Surface Reflectance 8-Day L3 Global 250m SIN Grid V006
land NASA LPCLOUD Level 3 HDF-EOS2
In plain English

What it measures. An estimate of the true color of the land surface, as if you removed the haze of the atmosphere. It records how much red and near-infrared light the ground reflects, at 250-meter detail, using the clearest view from each 8-day stretch.

How it's made. Produced from the MODIS sensor on NASA's Terra satellite, corrected for atmospheric effects like gases and aerosols and composited over 8 days to favor clear, cloud-free pixels.

How & where you'd use it. A staple for tracking vegetation, land cover, and seasonal change. Note: this version was retired in 2023, and users are pointed to the newer 6.1 version.

What's measured

LAND SURFACE › SURFACE RADIATIVE PROPERTIES › REFLECTANCE

Coverage & cadence

  • Time span2000-02-24 → 2023-02-17
  • Measured byTerra (MODIS)
  • Processing levelLevel 3
  • Spatial extent-180, -90, 180, 90
  • FormatsHDF-EOS2
  • StatusDEPRECATED

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 data product was decommissioned on July 31, 2023. Users are encouraged to use the [MOD09Q1 Version 6.1](https://doi.org/10.5067/MODIS/MOD09Q1.061) data product. The MOD09Q1 Version 6 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 * Striping due to a dead detector is noticeable for bands 5, 6, and 7 in scenes acquired February 24 through October 31, 2000. Corrections were implemented to reduce the striping in data acquired after November 1, 2000. Users should always check the band quality for dead detectors even though reflectance values may be in the valid range. * The Collection 6 MODIS Land Surface Reflectance product (MOD09) may [incorrectly flag retrievals as ‘High Aerosol’](https://landweb.modaps.eosdis.nasa.gov/displayissue?id=86) over brighter surfaces and at higher view angles. This will impact the downstream MODIS BRDF/Albedo (MCD43) and Vegetation Index (MOD13 and MYD13) data products which use the aerosol quantity flag to screen out high aerosol values. * [Corrections](https://landweb.modaps.eosdis.nasa.gov/data/userguide/LSRHighAerosolFlagFinal.pdf) were implemented in Collection 6.1 reprocessing. * 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=6).

Get the data

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

results = earthaccess.search_data(
    short_name="MOD09Q1",
    version="006",
    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.