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Full catalog/OMHCHO
OMHCHO·v003·dataset

Formaldehyde in the air (OMI/Aura)

OMI/Aura Formaldehyde (HCHO) Total Column 1-orbit L2 Swath 13x24 km V003 (OMHCHO) at GES DISC
atmosphere NASA GES_DISC Level 2 active
In plain English

What it measures. Maps how much formaldehyde gas is in the air column overhead, plus quality flags and location details. Formaldehyde is a marker of pollution and natural emissions from plants and fires.

How it's made. Measured by the Ozone Monitoring Instrument aboard NASA's Aura satellite, with one file covering the daylit part of each orbit (about 53 minutes, roughly 14 orbits a day).

How & where you'd use it. Helps researchers track air quality and the chemistry behind it, since formaldehyde is tied to emissions from vegetation, wildfires, and industrial activity.

What's measured

ATMOSPHERE › ATMOSPHERIC CHEMISTRY › CARBON AND HYDROCARBON COMPOUNDS › FORMALDEHYDE

Coverage & cadence

  • Time span2004-10-01 → ongoing
  • Measured byAura (OMI)
  • Processing levelLevel 2
  • 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 Aura Ozone Monitoring Instrument (OMI) Version-3 Formaldehyde Product OMHCHO is now available from the NASA Goddard Earth Sciences Data and Information Services Center (GES DISC) for the public access. The shortname for this Level-2 OMI total column Formaldehyde product is OMHCHO. The algorithm leads for this product are the US OMI scientists Dr. Kelly Chance and Dr. Thomas Kurosu from the Harvard-Smithsonian Center, Cambridge, MA. The OMHCHO product contains total vertical column HCHO, standard errors (rms and sigma), quality flags, geolocation and other ancillary information. The OMHCHO files are stored in the version 5 EOS Hierarchical Data Format (HDF-EOS5). Each file contains data from the day lit portion of an orbit (~53 minutes). There are approximately 14 orbits per day. The average file size for the OMHCHO data product is about 5 MB.

Get the data

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

results = earthaccess.search_data(
    short_name="OMHCHO",
    version="003",
    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.