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Full catalog/AMDBLWV
AMDBLWV·v2·dataset

Water vapor in the lowest air layer (daily, 1 degree)

AMSR-MODIS Boundary Layer Water Vapor L3 Daily 1 degree x 1 degree V2 (AMDBLWV) at GES DISC
atmosphere NASA GES_DISC Level 3
In plain English

What it measures. This estimates how much water vapor sits in the lowest layer of air over the ocean, beneath uniform cloud cover, on a daily one-degree grid. It captures the moisture between the sea surface and the base of the clouds.

How it's made. It combines two views: microwave readings from AMSR-E and AMSR-2 give the total moisture in the air column, while near-infrared imagery from MODIS gives the moisture above the clouds, and the difference yields the boundary-layer amount.

How & where you'd use it. Helps researchers study moisture in the marine atmosphere and the processes that form low ocean clouds.

What's measured

ATMOSPHERE › ATMOSPHERIC WATER VAPOR

Coverage & cadence

  • Time span2002-07-04 → 2017-12-31
  • Measured byAqua (AMSR-E, MODIS) · GCOM-W1 (AMSR2)
  • Processing levelLevel 3
  • 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

Version 2 is the current version of this dataset. Version 2 uses an improved methodology to screen out high clouds. This data set provides an estimate the marine boundary layer water vapor beneath uniform cloud fields. Microwave radiometry from AMSR-E and AMSR-2 provides the total column water vapor, while the near-infrared imagery from MODIS provides the water vapor above the cloud layers. The difference between the two gives the vapor between the surface and the cloud top, which may be interpreted as the boundary layer water vapor.

Get the data

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

results = earthaccess.search_data(
    short_name="AMDBLWV",
    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.