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Full catalog/M2TUNPODT
M2TUNPODT·v5.12.4·dataset

How ozone is changing by altitude, daily cycle (model)

MERRA-2 tavgU_3d_odt_Np: 3d,diurnal,Time-Averaged,Pressure-Level,Assimilation,Ozone Tendencies 0.625 x 0.5 degree V5.12.4 (M2TUNPODT) at GES DISC
atmosphere NASA GES_DISC Level 4 active
In plain English

What it measures. Tracks how ozone in the atmosphere is gaining or losing concentration at different altitudes, broken down by what's driving the change — chemistry, moist weather processes, or air movement. The numbers are averaged by month but kept separate for each 3-hour slot of the day so you can see the daily rhythm.

How it's made. It comes from MERRA-2, NASA's computer model that blends decades of satellite observations into a consistent picture of the atmosphere, processed onto a global grid across 42 pressure levels.

How & where you'd use it. Mainly a research input for studying how the ozone layer and air chemistry behave through the day; it's a building-block dataset for atmospheric scientists rather than something most people would open directly.

What's measured

ATMOSPHERE › ATMOSPHERIC CHEMISTRY › OXYGEN COMPOUNDS › ATMOSPHERIC OZONEATMOSPHERE › ATMOSPHERIC CHEMISTRY › OXYGEN COMPOUNDSATMOSPHERE › ATMOSPHERIC CHEMISTRY › OXYGEN COMPOUNDS › ATMOSPHERIC OZONE › OZONE PROFILES

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

M2TUNPODT (or tavgU_3d_odt_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 ozone tendencies on the 42 pressure levels, such as total ozone analysis tendency, tendency of odd oxygen mixing ratio due to chemistry, tendency of odd oxygen due to moist processes, and tendency of ozone due to dynamics. 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

m2tunpodt_access.py
import earthaccess
earthaccess.login(strategy="netrc")          # free Earthdata Login

results = earthaccess.search_data(
    short_name="M2TUNPODT",
    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.