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Full catalog/M2I1NXLFO
M2I1NXLFO·v5.12.4·dataset

Energy and water hitting the land surface (MERRA-2, hourly)

MERRA-2 inst1_2d_lfo_Nx: 2d,1-Hourly,Instantaneous,Single-Level,Assimilation,Land Surface Forcings 0.625 x 0.5 degree V5.12.4 (M2I1NXLFO) at GES DISC
atmosphere NASA GES_DISC Level 4 active
In plain English

What it measures. This provides the conditions of energy and water reaching the land surface every hour, including air temperature, humidity, wind, and surface height near the ground. These are snapshot values at the top of each hour.

How it's made. It comes from NASA's MERRA-2 reanalysis, a model that blends decades of satellite and other observations into a consistent global picture, here at roughly half-degree resolution from 1980 to the present.

How & where you'd use it. Useful as input for land, hydrology, and weather studies, and for anyone needing a continuous hourly history of surface conditions worldwide.

What's measured

ATMOSPHERE › ATMOSPHERIC PRESSURE › SURFACE PRESSUREATMOSPHERE › ATMOSPHERIC TEMPERATURE › SURFACE TEMPERATURE › AIR TEMPERATUREATMOSPHERE › ATMOSPHERIC WATER VAPOR › WATER VAPOR INDICATORS › HUMIDITY › SPECIFIC HUMIDITYATMOSPHERE › ATMOSPHERIC WINDS › SURFACE WINDSATMOSPHERE › ATMOSPHERIC WINDS › SURFACE WINDS › WIND SPEEDATMOSPHERE › ALTITUDE › GEOPOTENTIAL HEIGHT

Coverage & cadence

  • Time span1980-01-01 → ongoing
  • Measured byMERRA-2 (NOT APPLICABLE)
  • Processing levelLevel 4
  • Spatial extent-180, -90, 180, 90
  • 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

M2I1NXLFO (or inst1_2d_lfo_Nx) is an instantaneous 2-dimensional hourly data collection in Modern-Era Retrospective analysis for Research and Applications version 2 (MERRA-2). This collection consists of land surface forcing parameters, such as height, specific humidity, wind, and air temperature of the model surface layer. The timestamp of a data field is on each hour starting from 00:00 UTC, e.g.: 00:00, 01:00, … , 23:00 UTC. MERRA-2 is the latest version of global atmospheric reanalysis for the satellite era produced by NASA Global Modeling and Assimilation Office (GMAO) using the Goddard Earth Observing System Model (GEOS) version 5.12.4. The dataset covers the period of 1980-present with the latency of ~3 weeks after the end of a month. Data Reprocessing: Please check “Records of MERRA-2 Data Reprocessing and Service Changes” linked from the “Documentation” tab on this page. Note that a reprocessed data filename is different from the original file. MERRA-2 Mailing List: Sign up to receive information on reprocessing of data, changing of tools and services, as well as data announcements from GMAO. Contact the GES DISC Help Desk (gsfc-dl-help-disc@mail.nasa.gov) to be added to the list. Questions: If you have a question, please read "MERRA-2 File Specification Document", “MERRA-2 Data Access – Quick Start Guide”, and FAQs linked from the ”Documentation” tab on this page. If that does not answer your question, you may post your question to the NASA Earthdata Forum (forum.earthdata.nasa.gov) or email the GES DISC Help Desk (gsfc-dl-help-disc@mail.nasa.gov).

Get the data

m2i1nxlfo_access.py
import earthaccess
earthaccess.login(strategy="netrc")          # free Earthdata Login

results = earthaccess.search_data(
    short_name="M2I1NXLFO",
    version="5.12.4",
    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.