Earth Data School
About
Full catalog/M2T3NPCLD
M2T3NPCLD·v5.12.4·dataset

Modeled cloud conditions at altitude, every 3 hours

MERRA-2 tavg3_3d_cld_Np: 3d,3-Hourly,Time-Averaged,Pressure-Level,Assimilation,Cloud Diagnostics 0.625 x 0.5 degree V5.12.4 (M2T3NPCLD) at GES DISC
atmosphere NASA GES_DISC Level 4 active
In plain English

What it measures. Modeled cloud conditions at many altitudes, every three hours, including how much of the sky is cloudy at each pressure level and how much cloud water or ice is present.

How it's made. Not a direct satellite snapshot but output from MERRA-2, NASA's reanalysis that blends decades of satellite and other observations through a weather model onto a global grid.

How & where you'd use it. Used in climate and weather research to study cloud behavior and as consistent input for studies needing cloud information spanning 1980 to the present.

What's measured

ATMOSPHERE › ATMOSPHERIC WATER VAPOR › WATER VAPOR INDICATORS › HUMIDITY › RELATIVE HUMIDITYATMOSPHERE › CLOUDS › CLOUD MICROPHYSICS › CLOUD LIQUID WATER/ICEATMOSPHERE › CLOUDS › CLOUD MICROPHYSICS › CLOUD OPTICAL DEPTH/THICKNESSATMOSPHERE › CLOUDS › CLOUD PROPERTIESATMOSPHERE › CLOUDS › CLOUD PROPERTIES › CLOUD FRACTIONATMOSPHERE › CLOUDS › CLOUD MICROPHYSICS › CLOUD MASS FLUX

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

M2T3NPCLD (or tavg3_3d_cld_Np) 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 cloud diagnostics on the 42 pressure levels, such as updraft areal fraction, cloud fraction for radiation , in-cloud cloud liquid (or ice) for radiation, and mass fraction of cloud liquid (or ice) water. The data field is available every three hour starting from 01:30 UTC, e.g.: 01:30, 04:30, … , 22:30 UTC. The information on the pressure levels can be found in the section 4.2 of the MERRA-2 File Specification document. 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

m2t3npcld_access.py
import earthaccess
earthaccess.login(strategy="netrc")          # free Earthdata Login

results = earthaccess.search_data(
    short_name="M2T3NPCLD",
    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.