Earth Data School
About
Full catalog/SNDR13CHRP1
SNDR13CHRP1·v2·dataset

Merged infrared brightness from many weather satellites

Sounder SIPS: Sun Synchronous 13:30 orbit Climate Hyperspectral InfraRed Product (CHIRP): Calibrated Radiances from EOS-Aqua, S-NPP, JPSS-1/NOAA-20, V2 (SNDR13CHRP1) at GES DISC
atmosphere NASA GES_DISC Level 1 active
In plain English

What it measures. A long, consistent record of how much infrared energy the atmosphere emits, recorded across many wavelengths, stitched together so different satellites' measurements line up on a common scale.

How it's made. A Level 1 radiance product that merges measurements from the AIRS instrument on Aqua and the CrIS instruments on Suomi-NPP and NOAA-20, choosing the best-performing instrument for each time period from 2002 onward.

How & where you'd use it. Provides a steady, cross-instrument infrared record useful for long-term climate studies; it's a foundational radiance input that feeds the retrievals scientists use to derive temperature, moisture, and other properties.

What's measured

ATMOSPHERE › AEROSOLS › DUST/ASH/SMOKEATMOSPHERE › ATMOSPHERIC CHEMISTRY › SULFUR COMPOUNDS › SULFUR DIOXIDESPECTRAL/ENGINEERING › INFRARED WAVELENGTHS › INFRARED RADIANCE

Coverage & cadence

  • Time span2002-09-01 → ongoing
  • Measured byAqua (AIRS) · Suomi-NPP (CrIS) · NOAA-20 (CrIS)
  • Processing levelLevel 1
  • Spatial extent-180, -90, 180, 90
  • 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

The Climate Hyperspectral Infrared Radiance Product (CHIRP) is a Level 1 radiance product derived from Atmospheric Infrared Sounder (AIRS) on EOS-AQUA and the Cross-Track Infrared Sounders (CrIS) on the SNPP and JPSS-1+ platforms. (JPSS-1 is also called NOAA-20). CHIRP provides a consistent spectral response function (SRF) across all instruments. Inter-instrument radiometric offsets are removed with SNPP-CrIS chosen as the "standard". CHIRP follows the original instrument storage, i.e., granule in, granule out, and contains all information needed for retrievals (including cross-track, along-track, fov id, etc.). This version of CHIRP, SNDR13CHRP1, is the primary CHIRP product which provides a full radiance record from 2002 onwards starting with AIRS from September 1, 2002 to August 30, 2016, switching to the SNPP CrIS instrument on September 1, 2016. The SNDR13CHRP1 product then switches to using JPSS-1 CrIS radiances starting September 1, 2018. This selection of time periods provides the best match to times when the microwave sounders on each of these platforms exhibited good performance and avoids long outages (such as SNPP CrIS in early Spring 2019). CHIRP is available for AIRS, CrIS-SNPP, and CrIS-JPSS-1 for time periods not used in the product distributed here, and are named SNDR13CHRP1AQCal, SNDR13CHRP1SNCal, and SNDR13CHRP1J1Cal respectively.

Get the data

sndr13chrp1_access.py
import earthaccess
earthaccess.login(strategy="netrc")          # free Earthdata Login

results = earthaccess.search_data(
    short_name="SNDR13CHRP1",
    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.