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Full catalog/M2TMNXSLV
M2TMNXSLV·v5.12.4·dataset

Monthly weather near the ground worldwide (MERRA-2)

MERRA-2 tavgM_2d_slv_Nx: 2d,Monthly mean,Time-Averaged,Single-Level,Assimilation,Single-Level Diagnostics 0.625 x 0.5 degree V5.12.4 (M2TMNXSLV) at GES DISC
atmosphere NASA GES_DISC Level 4 active
In plain English

What it measures. Monthly averages of everyday weather near the ground worldwide: air temperature, winds, surface pressure, sea-level pressure, and how much water vapor is in the air column.

How it's made. Generated by MERRA-2, NASA's model that merges satellite-era observations with weather modeling to produce a consistent record from 1980 onward, here averaged by month on a roughly half-degree grid.

How & where you'd use it. A go-to source for tracking long-term weather and climate patterns, comparing regions, and feeding research that needs a steady, gap-free record of surface conditions.

What's measured

ATMOSPHERE › ALTITUDE › GEOPOTENTIAL HEIGHTATMOSPHERE › ALTITUDEATMOSPHERE › ATMOSPHERIC TEMPERATURE › SURFACE TEMPERATUREATMOSPHERE › ATMOSPHERIC TEMPERATURE › UPPER AIR TEMPERATUREATMOSPHERE › ATMOSPHERIC TEMPERATURE › SURFACE TEMPERATURE › DEW POINT TEMPERATUREATMOSPHERE › ATMOSPHERIC TEMPERATURE › SURFACE TEMPERATURE › AIR TEMPERATUREATMOSPHERE › CLOUDS › CLOUD PROPERTIES › CLOUD TOP TEMPERATUREATMOSPHERE › ATMOSPHERIC WINDSATMOSPHERE › ATMOSPHERIC WINDS › SURFACE WINDSATMOSPHERE › ATMOSPHERIC WINDS › SURFACE WINDS › U/V WIND COMPONENTSATMOSPHERE › ATMOSPHERIC WINDS › UPPER LEVEL WINDSATMOSPHERE › ATMOSPHERIC WINDS › UPPER LEVEL WINDS › U/V WIND COMPONENTSATMOSPHERE › ATMOSPHERIC WINDS › WIND DYNAMICS › VERTICAL WIND VELOCITY/SPEEDATMOSPHERE › ATMOSPHERIC PRESSURE

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

M2TMNXSLV (or tavgM_2d_slv_Nx) is a time-averaged 2-dimensional monthly mean data collection in Modern-Era Retrospective analysis for Research and Applications version 2 (MERRA-2). This collection consists of meteorology diagnostics at popularly used vertical levels, such as air temperature at 2-meter (or at 10-meter, 850hPa, 500 hPa, 250hPa), wind components at 50-meter (or at 2-meter, 10-meter, 850hPa, 500hPa, 250 hPa), sea level pressure, surface pressure, and total precipitable water vapor (or ice water, liquid water). The collection also includes variance of certain parameters. 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

m2tmnxslv_access.py
import earthaccess
earthaccess.login(strategy="netrc")          # free Earthdata Login

results = earthaccess.search_data(
    short_name="M2TMNXSLV",
    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.