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Full catalog/M2T3NPRAD
M2T3NPRAD·v5.12.4·dataset

Modeled sunlight and heat through the air (MERRA-2, 3-hourly)

MERRA-2 tavg3_3d_rad_Np: 3d,3-Hourly,Time-Averaged,Pressure-Level,Assimilation,Radiation Diagnostics 0.625 x 0.5 degree V5.12.4 (M2T3NPRAD) at GES DISC
atmosphere NASA GES_DISC Level 4 active
In plain English

What it measures. Modeled, three-hourly averages of how sunlight and heat radiation move through the atmosphere, including things like cloud fraction and how air temperature changes due to longwave and shortwave radiation, across many altitude levels.

How it's made. Comes from MERRA-2, a NASA reanalysis that blends satellite-era observations with a global atmospheric model to produce a consistent record from 1980 to the present.

How & where you'd use it. Used by researchers studying Earth's energy balance, climate and weather, providing a complete and gap-free picture where direct observations are sparse.

What's measured

ATMOSPHERE › ATMOSPHERIC RADIATIONATMOSPHERE › ATMOSPHERIC TEMPERATURE › SURFACE TEMPERATURE › TEMPERATURE TENDENCYATMOSPHERE › CLOUDS › CLOUD PROPERTIES › CLOUD FRACTION

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

M2T3NPRAD (or tavg3_3d_rad_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 radiation diagnostics on 42 pressure levels, such as cloud fraction for radiation, and air temperature tendency due to longwave (or shortwave). 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

m2t3nprad_access.py
import earthaccess
earthaccess.login(strategy="netrc")          # free Earthdata Login

results = earthaccess.search_data(
    short_name="M2T3NPRAD",
    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.