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Full catalog/SWOT_L2_RAD_OGDR_2.0
SWOT_L2_RAD_OGDR_2.0·v2.0·dataset

Water vapor and brightness over ocean, near real-time (SWOT)

SWOT Level 2 Radiometer Brightness Temperatures and Troposphere Operational Data Product
land NASA POCLOUD Level 2 netCDF-4
In plain English

What it measures. How much water vapor and liquid water sit in the air over the ocean, plus cloud water and wind speed. This near-real-time version arrives fastest, within about seven hours.

How it's made. Produced from the Advanced Microwave Radiometer on the SWOT satellite (NASA and CNES), processed quickly using onboard orbit tracking and preliminary calibrations.

How & where you'd use it. Used to correct SWOT's ocean-height readings for atmospheric moisture in time-sensitive applications, trading some accuracy for speed.

What's measured

SPECTRAL/ENGINEERING › MICROWAVE › BRIGHTNESS TEMPERATUREATMOSPHERE › ATMOSPHERIC WATER VAPORSPECTRAL/ENGINEERING › RADAR › SIGMA NAUGHTATMOSPHERE › CLOUDS › CLOUD MICROPHYSICS › CLOUD LIQUID WATER/ICECRYOSPHERE › SEA ICEOCEANS › GEOLOGICAL FEATURES › LAND/OCEAN/ICE FRACTIONATMOSPHERE › ATMOSPHERIC WINDS › SURFACE WINDS › WIND SPEED

Coverage & cadence

  • Time span2022-12-16 → ongoing
  • Measured bySWOT (AMR)
  • Processing levelLevel 2
  • Spatial extent-180, -77.6, 180, 77.6
  • FormatsnetCDF-4
  • StatusSUPERSEDED

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 SWOT Level 2 Radiometer Brightness Temperatures and Troposphere Operational Geophysical Data Record (OGDR) Version 1.0 dataset produced by the Surface Water and Ocean Topography (SWOT) mission provides atmospheric water vapor and liquid water content from the Advanced Microwave Radiometer (AMR), a Jason-class radiometer that measures sea surface brightness temperatures at three microwave frequencies (18.7, 23.8 and 34 GHz). Brightness temperatures are processed to estimate the wet troposphere content, atmospheric attenuation to backscatter, cloud liquid water, water vapor content, and wind speed coincident with each range measurement from the nadir altimeter and applied to correct for altimeter range delays caused by atmospheric effects. SWOT is a joint mission between NASA and CNES that launched on December 16, 2022 and aims to measure ocean surface topography with unprecedented resolution and accuracy, as well as map inland water bodies globally. The operational radiometer dataset consists of discrete measurements along two tracks located approximately 30-km to the left and right of the satellite nadir. They were processed using the onboard DORIS orbit ephemeris and preliminary calibrations. They are distributed as one file per data downlink in netCDF-4 file format with a nominal latency of < 7 hours.

Get the data

swot_l2_rad_ogdr_2.0_access.py
import earthaccess
earthaccess.login(strategy="netrc")          # free Earthdata Login

results = earthaccess.search_data(
    short_name="SWOT_L2_RAD_OGDR_2.0",
    version="2.0",
    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 POCLOUD
Browsing CMR needs no login. Downloading or streaming bytes needs a free Earthdata Login + the earthaccess package.