Full catalog/g3btb
g3btb·v53·dataset

Raw sunlight dimming, native format (newer version)

SAGE III/ISS L1B Solar Event Transmission Data (Native) V053
atmosphere NASA LARC_CLOUD Level 1B Binary
In plain English

What it measures. Profiles of how much sunlight made it through Earth's atmosphere at a single sunrise or sunset, by altitude.

How it's made. A raw Level 1B product from the SAGE III instrument on the International Space Station, in its native file format, from observing sunlight passing through the atmosphere's limb.

How & where you'd use it. A building-block input that higher-level products turn into measurements of upper-atmosphere ozone, aerosols, and trace gases; not usually used directly. A few March 2024 events are flagged as unreliable.

What's measured

ATMOSPHERE › ATMOSPHERIC RADIATIONATMOSPHERE › ATMOSPHERIC RADIATION › ULTRAVIOLET RADIATIONATMOSPHERE › ATMOSPHERIC RADIATION › SHORTWAVE RADIATIONATMOSPHERE › ATMOSPHERIC RADIATION › LONGWAVE RADIATION

Coverage & cadence

  • Time span2017-06-07 → 2024-11-30
  • Measured byISS (SAGE III)
  • Processing levelLevel 1B
  • Spatial extent-180, -90, 180, 90
  • FormatsBinary
  • 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

Data quality notice: The SAGE III/ISS team recommends against using data from events 2024030913SS, 2024030915SS, and 2024030917SS. These events were affected by line-of-sight blockage from a docked spacecraft which undermined the data quality. Typically, such events are withheld by a quality assurance process. g3btb_53 is the Stratospheric Aerosol and Gas Experiment III (SAGE III) on the International Space Station (ISS) (SAGE III/ISS) Level 1B Solar Event Transmission Data (Native) V053 data product. It contains pixel group transmission profiles for a single solar event. Launched on February 19, 2017 on a SpaceX Falcon 9 from Kennedy Space Center, the Stratospheric Aerosol and Gas Experiment III on the International Space Station (SAGE III/ISS), the second instrument from the SAGE III project, is externally mounted on the International Space Station (ISS). This ISS-based instrument uses a technique known as occultation, which involves looking at the light from the Sun or Moon as it passes through Earth’s atmosphere at the edge, or limb, of the planet to provide long-term monitoring of ozone vertical profiles of the stratosphere and mesosphere. The data provided by SAGE III/ISS includes other key components of atmospheric composition and their long-term variability, focusing on the study of aerosols, nitrogen dioxide, nitrogen trioxide, and water vapor. SAGE data has historically been used by the World Meteorological Organization to inform their periodic assessments of ozone depletion. These new observations from the International Space Station will continue the SAGE team's contributions to ongoing scientific understanding of the Earth's atmosphere. Several improvements predominately the ozone, nitrogen dioxide and aerosol products are realized in the version 6.0 data product and cause it to be recommended over version 5.3. These improvements include: filling transmission gaps (caused mainly by sunspots) leading to several hundred more events, additional term in L1 uncertainty, updated ozone absorption cross-section database, more robust covariance computation of aerosol uncertainty. Version 6.0 also has incorporated aerosol flags and particle size distribution information which were previously available in separate files. Further details can be found in the version 6.0 release notes.

Get the data

g3btb_access.py
import earthaccess
earthaccess.login(strategy="netrc")          # free Earthdata Login

results = earthaccess.search_data(
    short_name="g3btb",
    version="53",
    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 LARC_CLOUD
Browsing CMR needs no login. Downloading or streaming bytes needs a free Earthdata Login + the earthaccess package.