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Full catalog/M2I3NVASM
M2I3NVASM·v5.12.4·dataset

3D weather through the atmosphere by altitude (MERRA-2)

MERRA-2 inst3_3d_asm_Nv: 3d,3-Hourly,Instantaneous,Model-Level,Assimilation,Assimilated Meteorological Fields 0.625 x 0.5 degree V5.12.4 (M2I3NVASM) at GES DISC
atmosphere NASA GES_DISC Level 4 active
In plain English

What it measures. A 3D picture of the atmosphere by altitude every 3 hours: temperature, wind, vertical air motion, humidity, and layer heights across 72 vertical levels from the surface to the top of the atmosphere.

How it's made. Part of NASA's MERRA-2 reanalysis, which blends satellite and other observations into a global weather model to reconstruct conditions at every level, rather than being a single direct measurement.

How & where you'd use it. Used to study atmospheric structure, weather and climate processes, and to drive other models, offering a consistent record back to 1980.

What's measured

ATMOSPHERE › ATMOSPHERIC CHEMISTRY › OXYGEN COMPOUNDS › ATMOSPHERIC OZONEATMOSPHERE › ATMOSPHERIC PRESSURE › SEA LEVEL PRESSUREATMOSPHERE › ATMOSPHERIC PRESSURE › SURFACE PRESSUREATMOSPHERE › ATMOSPHERIC PRESSURE › PRESSURE THICKNESSATMOSPHERE › ATMOSPHERIC WINDS › SURFACE WINDS › U/V WIND COMPONENTSATMOSPHERE › ATMOSPHERIC WINDS › UPPER LEVEL WINDS › U/V WIND COMPONENTSATMOSPHERE › ATMOSPHERIC WINDS › WIND DYNAMICS › VORTICITY › POTENTIAL VORTICITYATMOSPHERE › ATMOSPHERIC WINDS › WIND DYNAMICS › VERTICAL WIND VELOCITY/SPEEDATMOSPHERE › ATMOSPHERIC TEMPERATURE › UPPER AIR TEMPERATURE › VERTICAL PROFILESATMOSPHERE › ATMOSPHERIC TEMPERATURE › UPPER AIR TEMPERATUREATMOSPHERE › ATMOSPHERIC TEMPERATURE › SURFACE TEMPERATURE › AIR TEMPERATUREATMOSPHERE › ATMOSPHERIC WATER VAPOR › WATER VAPOR INDICATORS › HUMIDITY › RELATIVE HUMIDITYATMOSPHERE › ATMOSPHERIC WATER VAPOR › WATER VAPOR INDICATORS › HUMIDITY › SPECIFIC HUMIDITYATMOSPHERE › ATMOSPHERIC WATER VAPOR

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

M2I3NVASM (or inst3_3d_asm_Nv) is an instantaneous 3-dimensional 3-hourly 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 temperature, wind components, vertical pressure velocity, water vapor, and layer height. The data field is available every three hour starting from 00:00 UTC, e.g.: 00:00, 03:00, … , 21:00 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

m2i3nvasm_access.py
import earthaccess
earthaccess.login(strategy="netrc")          # free Earthdata Login

results = earthaccess.search_data(
    short_name="M2I3NVASM",
    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.