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Full catalog/NLDAS_FORA0125_M
NLDAS_FORA0125_M·v2.0·dataset

Weather inputs feeding U.S. land models (monthly)

NLDAS Primary Forcing Data L4 Monthly 0.125 x 0.125 degree V2.0 (NLDAS_FORA0125_M) at GES DISC
atmosphere NASA GES_DISC Level 4 active
In plain English

What it measures. Monthly weather conditions used to drive U.S. land models - including precipitation, evaporation potential, and other meteorological fields - on a fine grid covering North America back to 1979.

How it's made. Generated by summing or averaging the hourly North American Land Data Assimilation System forcing data into monthly values, delivered in NetCDF format.

How & where you'd use it. A building-block input that feeds land-surface models studying soil moisture, runoff, and drought; it's the fuel for models rather than a direct observation of the landscape.

What's measured

ATMOSPHERE › ATMOSPHERIC PRESSURE › SURFACE PRESSUREATMOSPHERE › ATMOSPHERIC RADIATION › LONGWAVE RADIATIONATMOSPHERE › ATMOSPHERIC RADIATION › SHORTWAVE RADIATIONATMOSPHERE › ATMOSPHERIC TEMPERATURE › SURFACE TEMPERATUREATMOSPHERE › ATMOSPHERIC WATER VAPOR › WATER VAPOR INDICATORS › HUMIDITYATMOSPHERE › ATMOSPHERIC WATER VAPOR › WATER VAPOR PROCESSES › EVAPORATIONATMOSPHERE › ATMOSPHERIC WINDS › SURFACE WINDSATMOSPHERE › ATMOSPHERIC WINDS › WIND DYNAMICS › CONVECTIONATMOSPHERE › 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 product contains the monthly primary forcing data "File A" 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 data files). The NLDAS-2 monthly primary forcing data were generated from the NLDAS-2 hourly primary forcing data, as monthly accumulation for total precipitation, convective precipitation, and potential evaporation, and monthly average for other variables. The convective precipitation monthly total is the hourly convective fraction multiplied by the hourly precipitation (both from the NLDAS-2 "File A" files), and then summed over all hours of the month. 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 A" is the primary (default) forcing file and contains eleven 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_fora0125_m_access.py
import earthaccess
earthaccess.login(strategy="netrc")          # free Earthdata Login

results = earthaccess.search_data(
    short_name="NLDAS_FORA0125_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.