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Full catalog/M2T3NVASM
M2T3NVASM·v5.12.4·dataset

3-D weather model through the atmosphere (MERRA-2)

MERRA-2 tavg3_3d_asm_Nv: 3d,3-Hourly,Time-Averaged,Model-Level,Assimilation,Assimilated Meteorological Fields 0.625 x 0.5 degree V5.12.4 (M2T3NVASM) at GES DISC
atmosphere NASA GES_DISC Level 4 active
In plain English

What it measures. A three-dimensional snapshot of the atmosphere every 3 hours, giving air temperature, winds, water vapor, and other weather variables across 72 stacked layers from the surface up high.

How it's made. Produced by NASA's MERRA-2 reanalysis, which blends a weather model with satellite-era observations to fill in a complete, consistent picture.

How & where you'd use it. Used to study atmospheric structure, weather patterns, and long-term climate, and as input for other models, covering 1980 to the present.

What's measured

ATMOSPHERE › ALTITUDE › GEOPOTENTIAL HEIGHTATMOSPHERE › ATMOSPHERIC CHEMISTRY › OXYGEN COMPOUNDS › ATMOSPHERIC OZONEATMOSPHERE › ATMOSPHERIC PRESSURE › PRESSURE THICKNESSATMOSPHERE › ATMOSPHERIC PRESSURE › SEA LEVEL PRESSUREATMOSPHERE › ATMOSPHERIC PRESSURE › SURFACE PRESSUREATMOSPHERE › ATMOSPHERIC TEMPERATURE › SURFACE TEMPERATURE › AIR TEMPERATUREATMOSPHERE › ATMOSPHERIC TEMPERATURE › UPPER AIR TEMPERATUREATMOSPHERE › ATMOSPHERIC WATER VAPORATMOSPHERE › CLOUDS › CLOUD MICROPHYSICS › CLOUD LIQUID WATER/ICEATMOSPHERE › CLOUDS › CLOUD PROPERTIES › CLOUD FRACTIONATMOSPHERE › ATMOSPHERIC WINDS › SURFACE WINDS › U/V WIND COMPONENTSATMOSPHERE › ATMOSPHERIC WINDS › UPPER LEVEL WINDS › U/V WIND COMPONENTSATMOSPHERE › ATMOSPHERIC CHEMISTRY › OXYGEN COMPOUNDS › ATMOSPHERIC OZONE › OZONE PROFILES

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

M2T3NVASM (or tavg3_3d_asm_Nv) is a 3-dimensional 3-hourly time averaged data collection in Modern-Era Retrospective analysis for Research and Applications version 2 (MERRA-2). This collection consists of assimilations of meteorological parameters at 72 model layers, such as air temperature, wind components, vertical pressure velocity, water vapor, and layer height. The data field is available every three hour starting from 01:30 UTC, e.g.: 01:30, 04:30, … , 22:30 UTC. Section 4.2 of the MERRA-2 File Specification document provides pressure values nominal for a 1000 hPa surface pressure and refers to the top edge of the layer. The lev=1 is for the top layer, and lev=72 is for the bottom (or surface) model layer. 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

m2t3nvasm_access.py
import earthaccess
earthaccess.login(strategy="netrc")          # free Earthdata Login

results = earthaccess.search_data(
    short_name="M2T3NVASM",
    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.