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Full catalog/M2T1NXSLV
M2T1NXSLV·v5.12.4·dataset

Hourly weather near the ground worldwide (MERRA-2)

MERRA-2 tavg1_2d_slv_Nx: 2d,1-Hourly,Time-Averaged,Single-Level,Assimilation,Single-Level Diagnostics 0.625 x 0.5 degree V5.12.4 (M2T1NXSLV) at GES DISC
atmosphere NASA GES_DISC Level 4 active
In plain English

What it measures. Hourly snapshots of basic weather near the ground everywhere on Earth: air temperature at a few standard heights, wind speed and direction, sea-level and surface pressure, and how much water vapor is in the air column. Each value is the average over one hour.

How it's made. It comes from MERRA-2, NASA's reconstruction of past weather that blends decades of satellite observations into a computer model on a roughly half-degree global grid.

How & where you'd use it. Handy for studying weather and climate patterns since 1980, comparing conditions across regions and years, and feeding other models that need a consistent picture of the atmosphere.

What's measured

ATMOSPHERE › ALTITUDE › GEOPOTENTIAL HEIGHTATMOSPHERE › ALTITUDEATMOSPHERE › ATMOSPHERIC TEMPERATURE › SURFACE TEMPERATUREATMOSPHERE › ATMOSPHERIC TEMPERATURE › SURFACE TEMPERATURE › SKIN 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/SPEED

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

M2T1NXSLV (or tavg1_2d_slv_Nx) is an hourly time-averaged 2-dimensional 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, 850 hPa, 500hPa, 250 hPa), sea level pressure, surface pressure, and total precipitable water vapor (or ice water, liquid water). The data field is time-stamped with the central time of an hour starting from 00:30 UTC, e.g.: 00:30, 01:30, … , 23:30 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

m2t1nxslv_access.py
import earthaccess
earthaccess.login(strategy="netrc")          # free Earthdata Login

results = earthaccess.search_data(
    short_name="M2T1NXSLV",
    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.