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Full catalog/M2T3NXGLC
M2T3NXGLC·v5.12.4·dataset

Modeled snow and ice on land, every 3 hours

MERRA-2 tavg3_2d_glc_Nx: 2d,3-Hourly,Time-Averaged,Single-Level,Assimilation,Land Ice Surface Diagnostics 0.625 x 0.5 degree V5.12.4 (M2T3NXGLC) at GES DISC
cryosphere NASA GES_DISC Level 4 active
In plain English

What it measures. Modeled conditions of snow and ice sitting on glaciated land, such as how much of the surface is covered in snow, the weight of that snow, and its depth, every three hours.

How it's made. Comes from NASA's MERRA-2 reanalysis, which blends decades of satellite-era observations with a weather model to produce a consistent picture, gridded at roughly half a degree.

How & where you'd use it. Helps researchers study snow and ice on land over time and supplies inputs for climate and water studies. It is modeled output rather than a direct camera image.

What's measured

CRYOSPHERE › SNOW/ICE › ALBEDOCRYOSPHERE › SNOW/ICE › SNOW DEPTHCRYOSPHERE › SEA ICE › SNOW DEPTHTERRESTRIAL HYDROSPHERE › GLACIERS/ICE SHEETS › GLACIERS › GLACIER RUNOFFCRYOSPHERE › GLACIERS/ICE SHEETS › GLACIERS › GLACIER RUNOFFCRYOSPHERE › SNOW/ICE › SNOW COVER

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

  • Measure sea ice, snow cover and glaciers
  • Watch ice-sheet elevation change
  • Track freeze/thaw and permafrost
Official description

M2T3NXGLC (or tavg3_2d_glc_Nx) is a 2-dimensional 3-hourly time-averaged data collection in Modern-Era Retrospective analysis for Research and Applications version 2 (MERRA-2). This collection consists of assimilated land ice surface diagnostics at the single levels, such as fractional area of glaciated surface snow cover, snow mass over glaciated surface, snow depth over glaciated surface, and total snow mass residual due to densification. The data field is available every three hour starting from 01:30 UTC, e.g.: 01:30, 04:30, … , 22:30 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

m2t3nxglc_access.py
import earthaccess
earthaccess.login(strategy="netrc")          # free Earthdata Login

results = earthaccess.search_data(
    short_name="M2T3NXGLC",
    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.