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Full catalog/M2TUNPTDT
M2TUNPTDT·v5.12.4·dataset

How air temperature changes through the day, by altitude (MERRA-2)

MERRA-2 tavgU_3d_tdt_Np: 3d,diurnal,Time-Averaged,Pressure-Level,Assimilation,Temperature Tendencies 0.625 x 0.5 degree V5.12.4 (M2TUNPTDT) at GES DISC
atmosphere NASA GES_DISC Level 4 active
In plain English

What it measures. How air temperature tends to change over the course of an average day at many altitudes, broken down by the cause of the change (such as motion of the air, moisture, or radiation). Reported as monthly averages.

How it's made. Produced by MERRA-2, a NASA reanalysis that blends decades of satellite-era observations with a weather model to reconstruct a consistent picture of the atmosphere.

How & where you'd use it. A research tool for understanding the daily rhythm of atmospheric temperature changes and the physical processes driving them, mainly used in climate and atmospheric modeling.

What's measured

ATMOSPHERE › ATMOSPHERIC TEMPERATURE › UPPER AIR TEMPERATUREATMOSPHERE › ATMOSPHERIC TEMPERATURE › SURFACE TEMPERATURE › AIR TEMPERATUREATMOSPHERE › ATMOSPHERIC TEMPERATURE › SURFACE TEMPERATURE › TEMPERATURE TENDENCY

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

M2TUNPTDT (or tavgU_3d_tdt_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 air temperature tendencies on 42 pressure levels, such as total temperature analysis tendency, and tendency of air temperature due to dynamics (or friction, moisture, radiation, and physics). 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 and 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

m2tunptdt_access.py
import earthaccess
earthaccess.login(strategy="netrc")          # free Earthdata Login

results = earthaccess.search_data(
    short_name="M2TUNPTDT",
    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.