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Full catalog/SNDRJ1ATMSL1B
SNDRJ1ATMSL1B·v3·dataset

Microwave temperatures used to sound the atmosphere (JPSS-1)

JPSS-1 ATMS Level 1B Brightness Temperature V3 (SNDRJ1ATMSL1B) at GES DISC
land NASA GES_DISC Level 1B active
In plain English

What it measures. Records how much natural microwave energy comes up from the atmosphere across 22 channels at different frequencies, expressed as a 'brightness temperature' (how warm the atmosphere looks to the sensor at each frequency). Because different frequencies respond to different heights and to water vapor, this is the raw signal used to figure out the temperature and moisture of the air at many altitudes.

How it's made. Built from the Advanced Technology Microwave Sounder (ATMS), a microwave radiometer on the NOAA-20 (JPSS-1) satellite, calibrated and packaged with location and timing info but not yet turned into weather variables (a Level 1B product).

How & where you'd use it. A building-block input that feeds weather forecasting models and atmospheric temperature and humidity products; most people use it indirectly through the forecasts and atmospheric profiles built from it rather than the raw brightness temperatures themselves.

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="3",
    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.