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Full catalog/M2TUNPRAD
M2TUNPRAD·v5.12.4·dataset

How sunlight heats the air through the day, by altitude (MERRA-2)

MERRA-2 tavgU_3d_rad_Np: 3d,diurnal,Time-Averaged,Pressure-Level,Assimilation,Radiation Diagnostics 0.625 x 0.5 degree V5.12.4 (M2TUNPRAD) at GES DISC
atmosphere NASA GES_DISC Level 4 active
In plain English

What it measures. How the atmosphere heats and cools through a typical day at different altitudes, captured as temperature changes from sunlight and heat radiation along with related cloud information, on 42 pressure levels.

How it's made. Produced by MERRA-2, a NASA 'reanalysis' that blends decades of satellite and other observations into a consistent computer-model picture of the atmosphere, here as monthly averages for each 3-hour slot of the day on a roughly 0.5-degree grid.

How & where you'd use it. Used by climate and atmospheric researchers to study the daily rhythm of how energy moves through the air, and as consistent background data for many studies spanning 1980 to today.

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

M2TUNPRAD (or tavgU_3d_rad_Np) is a 3-dimensional monthly diurnal means 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 information on the pressure levels can be found in the section 4.2 of the MERRA-2 File Specification document. This data collection is the monthly mean of data fields for each 3-hour that is time-stamped at the central time 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

m2tunprad_access.py
import earthaccess
earthaccess.login(strategy="netrc")          # free Earthdata Login

results = earthaccess.search_data(
    short_name="M2TUNPRAD",
    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.