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Full catalog/AIRS3C2M
AIRS3C2M·v005·dataset

Carbon dioxide high in the air, monthly (Aqua)

AIRS/Aqua L3 Monthly CO2 in the free troposphere (AIRS-only) 2.5 degrees x 2 degrees V005 (AIRS3C2M) at GES DISC
atmosphere NASA GES_DISC Level 3
In plain English

What it measures. Monthly maps of carbon dioxide concentrations in the middle layers of the atmosphere (roughly 6 to 10 km up), given as a fraction of the air.

How it's made. Produced from the AIRS infrared sounder on NASA's Aqua satellite, with individual retrievals averaged into grid cells about 2.5 by 2 degrees for each calendar month.

How & where you'd use it. Helps researchers track how carbon dioxide moves and changes high in the atmosphere over time, supporting climate studies.

What's measured

ATMOSPHERE › ATMOSPHERIC CHEMISTRY › CARBON AND HYDROCARBON COMPOUNDS › ATMOSPHERIC CARBON DIOXIDEATMOSPHERE › ATMOSPHERIC RADIATION › ABSORPTIONATMOSPHERE › ATMOSPHERIC RADIATION › RADIATIVE FORCING

Coverage & cadence

  • Time span2010-01-01 → 2017-02-28
  • Measured byAqua (AIRS)
  • Processing levelLevel 3
  • Spatial extent-180, -60, 180, 90
  • StatusCOMPLETE

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 Atmospheric Infrared Sounder (AIRS) is a grating spectrometer (R = 1200) aboard the second Earth Observing System (EOS) polar-orbiting platform, EOS Aqua. In combination with the Advanced Microwave Sounding Unit (AMSU) and the Humidity Sounder for Brazil (HSB), AIRS constitutes an innovative atmospheric sounding group of visible, infrared, and microwave sensors. This product is the AIRS mid-tropospheric Carbon Dioxide (CO2) Level 3 Monthly Gridded Retrieval, from the AIRS instrument on board of Aqua satellite. It is a monthly gridded data, at 2.5x2 deg (lon)x(lat) grid cell size. The data is in mole fraction units (data x 10^6 =ppm in volume). This quantity is not a total column quantity because the sensitivity function of the AIRS mid-tropospheric CO2 retrieval system peaks over the altitude range 6-10 km. The quantity is what results when the true atmospheric CO2 profile is weighted, level-by-level, by the AIRS sensitivity function. The file format is HDF-EOS 2.12 corresponding to HDF4. This AIRS mid-tropospheric CO2 Level 3 Monthly Gridded Retrieval Product contains standard retrieval means, standard deviations and input counts as well as the latitude and longitude arrays giving the centers of the grid boxes. Each file covers a calendar month. The mean values are simply the arithmetic means of the individual CO2 retrievals which fall within that grid box over the month. The mid-tropospheric CO2 retrievals have been averaged and binned into 2.5 degree longitude x 2 degree latitude grid cells, from -180.0 to +180.0 deg longitude and from -60.0 to +90.0 deg latitude. For each grid map of 4-byte floating-point mean values there is a corresponding 4-byte floating-point map of standard deviation and a 2-byte integer grid map of counts. The counts map provides the user with the number of points per bin that were included in the mean.

Get the data

airs3c2m_access.py
import earthaccess
earthaccess.login(strategy="netrc")          # free Earthdata Login

results = earthaccess.search_data(
    short_name="AIRS3C2M",
    version="005",
    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.