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Full catalog/OMPS_N20_NMHCHO_L2
OMPS_N20_NMHCHO_L2·v1·dataset

Formaldehyde gas in the air (NOAA-20)

OMPS-N20 L2 NM Formaldehyde (HCHO) Total Column swath orbital
atmosphere NASA GES_DISC Level 2 active
In plain English

What it measures. This measures the total amount of formaldehyde gas in the air column over each location. Formaldehyde is a short-lived gas tied to natural plant emissions and to pollution.

How it's made. It comes from the OMPS Nadir-Mapper instrument on the NOAA-20 satellite, which derives the formaldehyde amount from ultraviolet light it records over each ground footprint.

How & where you'd use it. Useful for studying air quality and the chemistry that produces ozone, and for tracking emissions from vegetation, wildfires, and industry.

What's measured

ATMOSPHERE › ATMOSPHERIC CHEMISTRY › CARBON AND HYDROCARBON COMPOUNDS › FORMALDEHYDE

Coverage & cadence

  • Time span2018-01-16 → ongoing
  • Measured byNOAA-20 (OMPS)
  • 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 OMPS-N20 L2 NM Formaldehyde (HCHO) Total Column swath orbital product provides formaldehyde measurements from the Ozone Mapping and Profiling Suite (OMPS) Nadir-Mapper (NM) instrument on the NOAA-20 (JPSS-1) satellite. The total column HCHO amount is derived from radiances at wavelengths between 328.5 and 356.5 nm. Each granule contains data from the daylight portion of each orbit measured for a full day. Spatial coverage is global (-90 to 90 degrees latitude), and there are about 14.5 orbits per day. Each has typically 1201 swaths. The swath width of the NM is about 2800 km. Prior to orbit 6419 on 13 February 2019, each swath has 104 scenes, or pixels, with a footprint size of 17 km x 17 km at nadir. Orbits 6419 and later have 140 scenes across the swath, with a footprint size of 12 km x 17 km. The files are written in the new netCDF version 4 format.

Get the data

omps_n20_nmhcho_l2_access.py
import earthaccess
earthaccess.login(strategy="netrc")          # free Earthdata Login

results = earthaccess.search_data(
    short_name="OMPS_N20_NMHCHO_L2",
    version="1",
    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.