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Full catalog/TOMSN7L2
TOMSN7L2·v008·dataset

Total ozone overhead (early TOMS satellite)

TOMS Nimbus-7 Ozone (O3) Total Column 1-Orbit L2 Swath 50 km x 50 km V008 (TOMSN7L2) at GES DISC
atmosphere NASA GES_DISC Level 2
In plain English

What it measures. The total amount of ozone in the column of air overhead, plus extras like a measure of UV-absorbing haze, surface reflectivity, cloud cover, and sulfur dioxide. Coverage is at roughly 50 km resolution.

How it's made. Collected by the TOMS instrument on the early Nimbus-7 satellite and reprocessed to a modern standard at NASA Goddard.

How & where you'd use it. A long-running record valued for studying the history of the ozone layer, including the discovery and tracking of the Antarctic ozone hole.

What's measured

ATMOSPHERE › ATMOSPHERIC CHEMISTRY › OXYGEN COMPOUNDS › ATMOSPHERIC OZONE › TOTAL OZONEATMOSPHERE › ATMOSPHERIC RADIATION › REFLECTANCE › REFLECTIVITYATMOSPHERE › AEROSOLS › AEROSOL OPTICAL DEPTH/THICKNESS › UV AEROSOL INDEX

Coverage & cadence

  • Time span1978-11-01 → 1993-05-06
  • Measured byNimbus-7 (TOMS)
  • Processing levelLevel 2
  • Spatial extent-180, -90, 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 Nimbus-7 Total Ozone Mapping Spectrometer (TOMS) version 8 orbital swath data product contains total column ozone, UV aerosol index, and Lambertian effective surface reflectivity (Rayleigh corrected) at approximately 50x50 km2 resolution (at nadir). This product also contains some auxiliary derived and ancillary parameters including N-values, SO2 index, cloud fraction, cloud pressure, ozone below clouds, terrain height, geolocation, solar and satellite viewing angles, and data quality flags. These data are stored in the version 5 EOS Hierarchical Data Format (HDF-EOS5). The TOMS data were produced by the Laboratory for Atmospheres at NASA Goddard Space Flight Center (Code 614).

Get the data

tomsn7l2_access.py
import earthaccess
earthaccess.login(strategy="netrc")          # free Earthdata Login

results = earthaccess.search_data(
    short_name="TOMSN7L2",
    version="008",
    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.