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Full catalog/NLDAS_FORB0125_M
NLDAS_FORB0125_M·v2.0·dataset

Extra weather inputs for land models (NLDAS, monthly)

NLDAS Secondary Forcing Data L4 Monthly 0.125 x 0.125 degree V2.0 (NLDAS_FORB0125_M) at GES DISC
atmosphere NASA GES_DISC Level 4 active
In plain English

What it measures. A set of supplementary weather inputs over North America, ten optional meteorological fields, summarized monthly on a fine roughly 12-km grid from 1979 onward.

How it's made. These 'File B' secondary forcing fields are assembled for the NLDAS-2 system by averaging or accumulating its hourly data into monthly values.

How & where you'd use it. A behind-the-scenes input used to drive land-surface models for water and climate studies; rarely used on its own.

What's measured

ATMOSPHERE › ALTITUDE › GEOPOTENTIAL HEIGHTATMOSPHERE › ATMOSPHERIC PRESSURE › SURFACE PRESSUREATMOSPHERE › ATMOSPHERIC RADIATION › SHORTWAVE RADIATIONATMOSPHERE › ATMOSPHERIC TEMPERATURE › SURFACE TEMPERATUREATMOSPHERE › ATMOSPHERIC WATER VAPOR › WATER VAPOR INDICATORS › HUMIDITYATMOSPHERE › ATMOSPHERIC WINDS › WIND DYNAMICS › CONVECTIONATMOSPHERE › ATMOSPHERIC WINDS › SURFACE WINDSATMOSPHERE › PRECIPITATION › LIQUID PRECIPITATION › RAINLAND SURFACE › SURFACE THERMAL PROPERTIES › LAND SURFACE TEMPERATURE

Coverage & cadence

  • Time span1979-01-01 → ongoing
  • Measured byForcing-LSM (NOT APPLICABLE)
  • Processing levelLevel 4
  • Spatial extent-125, 25, -67, 53
  • StatusACTIVE

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

This data set contains the monthly secondary forcing data "File B" for Phase 2 of the North American Land Data Assimilation System (NLDAS-2). The data are in 1/8th degree grid spacing and range from Jan 1979 to the present. The temporal resolution is monthly. The file format is netCDF (converted from the GRIB format). The NLDAS-2 monthly secondary forcing data were generated from the NLDAS-2 hourly secondary forcing data, as monthly accumulation for precipitation and convective precipitation and monthly average for other variables. Monthly period of each month is from 00Z at start of the month to 23:59Z at end of the month. The one exception to this is the first month (Jan. 1979) that starts from 00Z 02 Jan 1979, except for the monthly accumulated precipitation and convective precipitation that both start from 12Z 01 Jan 1979. The monthly land surface forcing fields for NLDAS-2 are grouped into two files, "File A" and "File B". "File B" is the secondary (optional) forcing file and contains ten meteorological forcing fields. Details about the generation of the NLDAS-2.0 forcing datasets can be found in Xia et al. (2012).

Get the data

nldas_forb0125_m_access.py
import earthaccess
earthaccess.login(strategy="netrc")          # free Earthdata Login

results = earthaccess.search_data(
    short_name="NLDAS_FORB0125_M",
    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 GES_DISC
Browsing CMR needs no login. Downloading or streaming bytes needs a free Earthdata Login + the earthaccess package.