Earth Data School
About
Full catalog/PREFIRE_SAT2_2B-FLX
PREFIRE_SAT2_2B-FLX·vR01·dataset

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

Polar Radiant Energy in the Far InfraRed Experiment (PREFIRE) Spectral Flux from PREFIRE Satellite 2 R01
atmosphere NASA LARC_CLOUD Level 2B active netCDF-4
In plain English

What it measures. How much heat energy, especially far-infrared, is escaping from the polar regions to space (spectral flux at the top of the atmosphere), plus the total outgoing longwave radiation and surface emissivity.

How it's made. Derived from the PREFIRE infrared spectrometer aboard one of two small PREFIRE CubeSats, processed from raw radiance measurements using an estimation method with weather and cloud inputs.

How & where you'd use it. Fills a long-standing gap by measuring polar heat loss that was rarely observed before, feeding climate and circulation models to improve predictions of Arctic and Antarctic change.

What's measured

ATMOSPHERE › ATMOSPHERIC RADIATION › RADIATIVE FLUXATMOSPHERE › ATMOSPHERIC RADIATION › EARTH RADIATION BUDGETATMOSPHERE › ATMOSPHERIC RADIATION › OUTGOING LONGWAVE RADIATIONATMOSPHERE › ATMOSPHERIC RADIATION › LONGWAVE RADIATION › UPWELLING LONGWAVE RADIATION

Coverage & cadence

  • Time span2024-06-29 → ongoing
  • Measured byPREFIRE-SAT2 (TIRS-PREFIRE)
  • Processing levelLevel 2B
  • Spatial extent-180, -84, 180, 84
  • FormatsnetCDF-4
  • StatusACTIVE

What you can do with it

  • Map air pollutants — NO₂, aerosols, ozone
  • Track greenhouse gases and Earth's energy budget
  • Feed weather and air-quality analysis
Official description

Polar Radiant Energy in the Far InfraRed Experiment (PREFIRE) Spectral Flux from PREFIRE Satellite 2 (PREFIRE_SAT2_2B-FLX) contains surface emissivity derived from data collected by the PREFIRE Thermal Infrared Spectrometer (TIRS-PREFIRE) aboard PREFIRE-SAT2. Dual CubeSats each carry a PREFIRE Thermal Infrared Spectrometer (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 models to predict future conditions more accurately.PREFIRE_SAT2_2B-FLX contains spectral flux at the top of atmosphere for all available TIRS-PREFIRE channels as derived from PREFIRE Spectral Radiance (PREFIRE_SAT2_1B-RAD) data using an Optimal Estimation retrieval with inputs from the PREFIRE_SAT2_2B-MSK (cloud mask), PREFIRE_SAT2_AUX-MET (Auxiliary Meteorology), and PREFIRE_SAT2_AUX-SAT collections. PREFIRE_SAT2_2B-FLX also contains the top-of-atmosphere Outgoing Longwave Radiation (OLR) broadband flux. The primary purpose of this collection is to assess the radiative activities over the polar regions to better quantify the energy budget there.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.The spectral flux data for the sister instrument aboard PREFIRE-SAT1 can be found in the PREFIRE_SAT1_2B-FLX collection.

Get the data

prefire_sat2_2b-flx_access.py
import earthaccess
earthaccess.login(strategy="netrc")          # free Earthdata Login

results = earthaccess.search_data(
    short_name="PREFIRE_SAT2_2B-FLX",
    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.