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Full catalog/MOD021KM
MOD021KM·v7·dataset

Calibrated raw imagery in many colors (Terra, 1 km)

MODIS/Terra Calibrated Radiances 5-Min L1B Swath 1000m V7
land NASA LAADS Level 1B active NetCDF-4
In plain English

What it measures. How much light and energy the sensor recorded across 36 color bands, from visible through infrared, at about one-kilometer detail. These are calibrated, location-tagged raw measurements.

How it's made. Generated from the raw sensor counts of the MODIS instrument on NASA's Terra satellite, calibrated into standard energy units and pinned to ground locations.

How & where you'd use it. A foundational building-block input that feeds nearly all higher-level MODIS products; most people use those derived products rather than this raw radiance directly.

What's measured

SPECTRAL/ENGINEERING › INFRARED WAVELENGTHS › INFRARED RADIANCESPECTRAL/ENGINEERING › INFRARED WAVELENGTHS › REFLECTED INFRAREDSPECTRAL/ENGINEERING › VISIBLE WAVELENGTHS › VISIBLE RADIANCE

Coverage & cadence

  • Time span2000-02-24 → ongoing
  • Measured byTerra (MODIS)
  • Processing levelLevel 1B
  • Spatial extent-180, -90, 180, 90
  • FormatsNetCDF-4
  • 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 Terra MODIS (Moderate resolution Imaging Spectroradiometer) Level-1B (L1B) product includes calibrated and geolocated at-aperture radiances for 36 bands generated from MODIS Level-1A raw sensor counts. The radiances are provided in watts/m2/micrometer (µm)/steradian. The Terra MODIS L1B product is a set of three datasets (MOD02QKM, MOD02HKM, and MOD021KM) that are produced to address the three spatial-resolution variations: 250 m, 500 m, and 1000 m. This 1000-meter product is with a short-name MOD021KM. It provides 1000-m calibrated radiances for the 29 Visible and Near-Infrared (VNIR) (bands 8 to 19) and Shortwave Infrared and Thermal Infrared (SWIR & TIR) (bands 20 to 36) bands. Each 1-km band has 10 detectors in the along-track direction. The MOD021KM product contains the twelve Science Data Sets (SDS) besides geolocation fields for latitude and longitude, quality flags, error estimates, etc. Besides data and information for the 1-km reflective solar and thermal emissive bands, aggregated 250-m and 500-m bands are also generated through simple weighting functions that are applied to the data at their native resolution. Band 26 is a reflective solar band (RSB), which is handled uniquely. Notwithstanding its RSB status, it is transmitted along with the thermal band data. Consequently, the band order for the night-mode data is re-organized so that the Band 26 data are written to the RSB 1-km SDSs and not to the emissive band SDSs. The v7.0 Terra MODIS MOD021KM in netCDF4 format represents the most current version of this product that has undergone around half-a-dozen reprocessing cycles in the last 2.5 decades. Each 1000-m swath granule or data-file temporally spans 5 minutes and its image dimensions measure 2,030 lines (along-track direction) by 1,354 samples (cross-track direction). The v7.0 collection’s data record starts from July 4, 2002 (2002–185). Consult the MODIS L1B User Guide to understand how to convert the per-pixel scaled integers to radiance or reflectance.

Get the data

mod021km_access.py
import earthaccess
earthaccess.login(strategy="netrc")          # free Earthdata Login

results = earthaccess.search_data(
    short_name="MOD021KM",
    version="7",
    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 LAADS
Browsing CMR needs no login. Downloading or streaming bytes needs a free Earthdata Login + the earthaccess package.