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Full catalog/PREFIRE_SAT1_2B-SFC
PREFIRE_SAT1_2B-SFC·vR01·dataset

How efficiently the polar surface emits heat (PREFIRE Sat 1)

Polar Radiant Energy in the Far InfraRed Experiment (PREFIRE) Surface Emissivity from PREFIRE Satellite 1 R01
atmosphere NASA LARC_CLOUD Level 2B active netCDF-4
In plain English

What it measures. How efficiently the polar surface gives off heat (emissivity), reported across the instrument's infrared channels. This shows how readily different surfaces, like ice or land, radiate energy.

How it's made. Calculated from PREFIRE Satellite 1's infrared radiance measurements using a retrieval method that draws on weather data and a cloud mask.

How & where you'd use it. Helps scientists better quantify how much heat the polar regions lose to space, improving understanding of the polar energy budget and climate models.

What's measured

ATMOSPHERE › ATMOSPHERIC RADIATION › EARTH RADIATION BUDGETATMOSPHERE › ATMOSPHERIC RADIATION › LONGWAVE RADIATION › UPWELLING LONGWAVE RADIATIONLAND SURFACE › SURFACE RADIATIVE PROPERTIES › EMISSIVITY

Coverage & cadence

  • Time span2024-07-24 → ongoing
  • Measured byPREFIRE-SAT1 (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) Surface Emissivity from PREFIRE Satellite 1 (PREFIRE_SAT1_2B-SFC) contains surface emissivity derived from data collected by the PREFIRE Thermal Infrared Spectrometer (TIRS-PREFIRE) aboard PREFIRE-SAT1. 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_SAT1_2B-SFC contains surface spectral emissivity for all available TIRS-PREFIRE channels as derived from PREFIRE Spectral Radiance (PREFIRE_SAT1_1B-RAD) data using an Optimal Estimation retrieval via a radiative transfer model with inputs from the PREFIRE_SAT1_AUX-MET (Auxiliary Meteorology) and PREFIRE_SAT1_2B-MSK (cloud mask) collections. The purpose of this collection is to assess surface emissivity over the polar regions to better quantify the polar radiative budget in those regions. Science data retrieval started July 24, 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 surface emissivity data for the sister instrument aboard PREFIRE-SAT2 can be found in the PREFIRE_SAT2_2B-SFC collection.

Get the data

prefire_sat1_2b-sfc_access.py
import earthaccess
earthaccess.login(strategy="netrc")          # free Earthdata Login

results = earthaccess.search_data(
    short_name="PREFIRE_SAT1_2B-SFC",
    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.