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Full catalog/TOMSEPAER
TOMSEPAER·v2·dataset

How much UV light haze and smoke absorb (TOMS)

TOMS/EP Near UV Aerosol Index and LER 1-Orbit L2 40x40km at GES DISC
atmosphere NASA GES_DISC Level 2
In plain English

What it measures. An index of how much ultraviolet light airborne particles like smoke and dust absorb, plus related readings like cloud fraction, reflectivity, and surface brightness.

How it's made. Comes from the TOMS instrument flown on the Earth Probe satellite, part of a multi-decade effort to build a consistent, calibrated record from several UV-observing sensors.

How & where you'd use it. Useful for tracking smoke, dust, and haze over land and building long-term records of air-quality and aerosol trends.

What's measured

ATMOSPHERE › AEROSOLS › AEROSOL OPTICAL DEPTH/THICKNESSATMOSPHERE › AEROSOLS › AEROSOL RADIANCEATMOSPHERE › CLOUDS › CLOUD MICROPHYSICS › CLOUD OPTICAL DEPTH/THICKNESSATMOSPHERE › CLOUDS › CLOUD PROPERTIES › CLOUD FRACTION

Coverage & cadence

  • Time span1996-07-16 → 2002-01-01
  • Measured byEP-TOMS (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

As part of the NASA's Making Earth System Data Records for Use in Research Environments (MEaSUREs) program, this projects describes a multi-decadal Fundamental Climate Data Record (FCDR) of calibrated radiances as well as an Earth System Data Record (ESDR) of aerosol properties over the continents derived from a 32-year record of satellite near-UV observations by three sensors. The TOMS Earth Probe version 2 Level-2 orbital data product consists of cloud fraction, cloud optical depth, normalized radiance, reflectivity, residue, and UV aerosol index at approximately 40x40 km resolution (at nadir). This product also contains ancillary variables for ocean corrected surface albedo and terrain pressure. Total Ozone Mapping Spectrometer (TOMS) instruments have been successfully flown in orbit aboard the Nimbus-7(Nov. 1978 - May 1993), Meteor-3 (Aug. 1991 - Dec. 1994), Earth Probe (June 1996 - December 2005), and ADEOS (Sep. 1996 - June 1997) satellites. These Level-2 data are stored in the Hierarchical Data Format 5 (HDF5) and are available from the Goddard Earth Sciences (GES) Data and Information Services Center (DISC).

Get the data

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

results = earthaccess.search_data(
    short_name="TOMSEPAER",
    version="2",
    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.