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Full catalog/PREFIRE_SAT2_1B-RAD
PREFIRE_SAT2_1B-RAD·vR01·dataset

Far-infrared heat escaping the poles (PREFIRE satellite 2)

PREFIRE Spectral Radiance from PREFIRE Satellite 2 R01
land NASA LARC_CLOUD Level 1B active netCDF-4
In plain English

What it measures. Calibrated, located measurements of far-infrared heat radiating away from Earth's polar regions, across 63 channels spanning mid- and far-infrared wavelengths. Most polar heat escapes in this far-infrared range that had rarely been measured before.

How it's made. Captured by the TIRS infrared spectrometer aboard the second PREFIRE CubeSat, then calibrated and matched to ground locations using the satellite's pointing data and an elevation map.

How & where you'd use it. Used to study the polar energy budget and as an input for follow-on products on outgoing energy, surface emissivity, clouds, temperature, and water vapor, helping improve climate models.

What's measured

SPECTRAL/ENGINEERING › INFRARED WAVELENGTHS › INFRARED RADIANCEATMOSPHERE › ATMOSPHERIC RADIATION › EARTH RADIATION BUDGETATMOSPHERE › ATMOSPHERIC RADIATION › LONGWAVE RADIATION › UPWELLING LONGWAVE RADIATION

Coverage & cadence

  • Time span2024-06-29 → ongoing
  • Measured byPREFIRE-SAT2 (TIRS-PREFIRE)
  • Processing levelLevel 1B
  • Spatial extent-180, -84, 180, 84
  • 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

PREFIRE (Polar Radiant Energy in the Far InfraRed Experiment) Spectral Radiance from PREFIRE Satellite 2 (PREFIRE_SAT2_1B-RAD) contains calibrated and geolocated radiance data retrieved from data collected by the PREFIRE Thermal Infrared Spectrometer (TIRS-PREFIRE) aboard PREFIRE-SAT2. Dual CubeSats each carry a TIRS-PREFIRE, a push broom spectrometer with 63 channels measuring mid- and far-infrared (FIR) radiation from approximately 5 to 53 µm. Most polar emissions are in the FIR but have not been measured on a large scale. PREFIRE aims to fill knowledge gaps in the global energy budget by more accurately characterizing polar emissions. This information will then be assimilated into global circulation and other climate models to predict future climates more accurately.PREFIRE_SAT2_1B-RAD data are processed by geolocating the calibrated radiance data in PREFIRE_SAT2_1A-RAD using the pointing and position telemeters in PREFIRE_SAT2_0-BUS-TLM and a Digital Elevation Map.The PREFIRE_SAT2_1B-RAD data are used to analyze the radiative budget in polar regions and as an input for Level 2 products: top-of-atmosphere spectral flux, surface spectral emissivity, and atmospheric properties such as cloud cover, temperature profiles, and water vapor profiles.Science data retrieval started June 29, 2024, and is ongoing. Geographic coverage is global, with the greatest concentration of data in the polar regions. Within the orbital swath there are eight distinct tracks of data associated with the eight separate spatial scenes for each PREFIRE-TIRS. At the beginning of the mission, the approximate scene footprint sizes were 11.8 km x 34.8 km (cross-track x along-track), with gaps between each scene of approximately 24.2 km. The entire swath was ~264 km across. Note that the scene footprint and swath sizes quoted here are for the orbit altitude soon after launch. However, the footprint size will slowly become smaller as the orbit altitude decreases with time. This data has a temporal resolution of 0.707 seconds and is available in netCDF-4.Calibrated and geolocated radiance data for the sister instrument aboard PREFIRE-SAT1 can be found in the PREFIRE_SAT1_1B-RAD collection.

Get the data

prefire_sat2_1b-rad_access.py
import earthaccess
earthaccess.login(strategy="netrc")          # free Earthdata Login

results = earthaccess.search_data(
    short_name="PREFIRE_SAT2_1B-RAD",
    version="R01",
    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 LARC_CLOUD
Browsing CMR needs no login. Downloading or streaming bytes needs a free Earthdata Login + the earthaccess package.