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Full catalog/OMPS_N21_LP_L1G_EV
OMPS_N21_LP_L1G_EV·v1.0·dataset

Raw light measured by the ozone limb sounder (NOAA-21)

OMPS-N21 L1G LP Radiance EV Wavelength-Altitude Grid swath orbital 3slit V1.0 (OMPS_N21_LP_L1G_EV) at GES DISC
land NASA GES_DISC Level 1B active
In plain English

What it measures. The raw amount of light the sensor recorded looking sideways through the atmosphere, across a wide range of wavelengths from ultraviolet to near-infrared, measured at many heights up to about 80 km.

How it's made. Calibrated Earth-viewing radiances from the OMPS Limb-Profiler instrument on the NOAA-21 satellite, captured in the daylight part of each orbit and organized onto a wavelength-and-altitude grid.

How & where you'd use it. This is a low-level input product mainly used to derive ozone and other atmospheric profiles; most people would use the higher-level products that come from it rather than these raw radiances directly.

What's measured

SPECTRAL/ENGINEERING › ULTRAVIOLET WAVELENGTHS › ULTRAVIOLET RADIANCESPECTRAL/ENGINEERING › VISIBLE WAVELENGTHS › VISIBLE RADIANCESPECTRAL/ENGINEERING › INFRARED WAVELENGTHS › INFRARED RADIANCE

Coverage & cadence

  • Time span2022-11-10 → ongoing
  • Measured byNOAA-21 (OMPS)
  • Processing levelLevel 1B
  • Spatial extent-180, -84, 180, 84
  • StatusACTIVE

What you can do with it

  • Track deforestation, fire scars and land-cover change
  • Monitor crop and vegetation health (NDVI/EVI)
  • Map how built-up vs. green an area is over time
Official description

The OMPS-N21 L1G LP Radiance EV Wavelength-Altitude Grid swath orbital 3slit product contains the calibrated earth-viewing radiances measured by the Ozone Mapping and Profiling Suite (OMPS) Limb-Profiler (LP) sensor on the NOAA 21 (JPSS-2) satellite. The LP L1G product measures radiances in the wavelength region from 280 nm to 1000 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 measuring three limb profiles spaced approximately 250 km in the cross-track direction. The profiles are measured from the ground up to about 80 km with a vertical resolution of the retrieved profiles of approximately 1-2 km. The data are written using the Hierarchical Data Format Version 5 or HDF5.

Get the data

omps_n21_lp_l1g_ev_access.py
import earthaccess
earthaccess.login(strategy="netrc")          # free Earthdata Login

results = earthaccess.search_data(
    short_name="OMPS_N21_LP_L1G_EV",
    version="1.0",
    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.