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Full catalog/AIRX3C2M
AIRX3C2M·v005·dataset

Carbon dioxide in the mid-atmosphere, monthly (AIRS)

AIRS/Aqua L3 Monthly CO2 in the free troposphere (AIRS+AMSU) 2.5 degrees x 2 degrees V005 (AIRX3C2M) at GES DISC
atmosphere NASA GES_DISC Level 3
In plain English

What it measures. Monthly maps of carbon dioxide in the middle layers of the atmosphere (roughly 6 to 10 km up), shown as concentration in grid boxes, rather than a full top-to-bottom column.

How it's made. Derived from the AIRS infrared sounder paired with a microwave instrument on the Aqua satellite, with individual retrievals averaged into a 2.5-by-2-degree monthly grid.

How & where you'd use it. Used to study how carbon dioxide moves and accumulates at mid-altitudes over time, contributing to research on the global carbon cycle and climate.

What's measured

ATMOSPHERE › ATMOSPHERIC RADIATION › ABSORPTIONATMOSPHERE › ATMOSPHERIC RADIATION › RADIATIVE FORCINGATMOSPHERE › ATMOSPHERIC CHEMISTRY › CARBON AND HYDROCARBON COMPOUNDS › ATMOSPHERIC CARBON DIOXIDE

Coverage & cadence

  • Time span2002-09-01 → 2012-02-29
  • Measured byAqua (AIRS, AMSU-A)
  • 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 and AMSU instruments on board of Aqua satellite. It is 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 x 2 deg 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

airx3c2m_access.py
import earthaccess
earthaccess.login(strategy="netrc")          # free Earthdata Login

results = earthaccess.search_data(
    short_name="AIRX3C2M",
    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.