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Full catalog/SNDRJ1ATMSL1B
SNDRJ1ATMSL1B·v2·dataset

Raw microwave brightness readings (NOAA-20 ATMS)

JPSS-1 ATMS Level 1B Brightness Temperature V2 (SNDRJ1ATMSL1B) at GES DISC
land NASA GES_DISC Level 1B active
In plain English

What it measures. Raw microwave brightness readings across 22 channels, essentially how much natural microwave energy the atmosphere emits at different frequencies, with timing and location for each scan.

How it's made. Collected by the ATMS microwave sounder on the NOAA-20 satellite as it scans across the ground, packaged with calibration and geolocation details.

How & where you'd use it. A foundational input used to build temperature, moisture, and weather-forecasting products; people typically use it through those derived products rather than on its own.

What's measured

SPECTRAL/ENGINEERING › MICROWAVE › ANTENNA TEMPERATURESPECTRAL/ENGINEERING › MICROWAVE › BRIGHTNESS TEMPERATURESPECTRAL/ENGINEERING › MICROWAVE › MICROWAVE RADIANCE

Coverage & cadence

  • Time span2017-11-29 → ongoing
  • Measured byNOAA-20 (ATMS)
  • Processing levelLevel 1B
  • Spatial extent-180, -90, 180, 90
  • 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 Advanced Technology Microwave Sounder (ATMS) Level 1B data files contain brightness temperature measurements along with ancillary spacecraft, instrument, and geolocation data of the ATMS instrument on the Joint Polar Satellite System-1 (JPSS-1) platform. This platform is also known as NOAA-20 (National Oceanic and Atmospheric Administration). The ATMS is a 22-channel mm-wave radiometer. The ATMS will measure upwelling radiances in six frequency bands centered at 23 GHz, 31 GHz, 50-58 GHz, 89 GHz, 66 GHz, and 183 GHz. The ATMS is a total power radiometer, with “through-the-antenna” radiometric calibration. Radiometric data is collected by a pair of antenna apertures, scanned by rotating flat plate reflectors. Scanning is performed cross-track to the satellite motion from sun to anti-sun, using the "integrate-while-scan" type data collection. The scan period is 8/3 second, synchronized to the Cross-track Infrared Sounder (CrIS) using a spacecraft provided scan synchronization pulse. Since the JPSS-1 satellite is orbiting at an altitude of about 830 km, the instantaneous spatial resolution on the ground at nadir is about 16 km, 32 km, or 75 km depending upon the channel. The brightness temperature data are contained in an array with 135 rows in the along-track direction, 96 columns in the cross-track direction, and a 3rd dimension for each of the 22 channels. The ATMS cross-track scan interval is 0.018 seconds and the along-track scan period is 8/3 seconds. Data products are constructed on six minute boundaries. If you were redirected to this page from a DOI from an older version, please note this is the current version of the product. Please contact the GES DISC user support if you need information about previous data collections.

Get the data

sndrj1atmsl1b_access.py
import earthaccess
earthaccess.login(strategy="netrc")          # free Earthdata Login

results = earthaccess.search_data(
    short_name="SNDRJ1ATMSL1B",
    version="2",
    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 GES_DISC
Browsing CMR needs no login. Downloading or streaming bytes needs a free Earthdata Login + the earthaccess package.