MERRA-2 FAQ: I am interested in using MERRA-2 for wind analysis

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MERRA-2 has zonal and meridional wind components at various vertical levels – for example at 2, 10, and 50 meters above the surface and at 850, 500, and 250 hPa pressure levels. MERRA-2 has three-dimensional wind profiles as well. The following table lists the data collections useful for wind analysis. For more information about wind variables, please read the MERRA-2 File Specification and additional MERRA-2 documentation on the MERRA-2 project page.

For information about the MERRA-2 wind products, please see the attached table. Download the PDF for links to the datasets.

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Notes for the table:
1. The variables SPEED and SPEEDMSX in the data collection M2T1NXFLX_5.12.4 are hourly mean surface wind speed and hourly maximum wind speed, respectively. Surface means the first model layer above the surface. The height of the model layers (HLML) varies with time and location (click here to see an example).

2. ANA = direct analysis products; ASM = assimilated state variables (please see the System Document for more information).

Time-averaged: consists of a continuous sequence of data averaged over the indicated interval and time-stamped with the central time of the interval, starting at 00:30 UTC for hourly, and 1:30 UTC for 3-hourly.

Instantaneous: consists of the data field on the hour starting at 00:00 UTC.

If you are interested in daily mean or monthly mean wind speed and direction, you may calculate the hourly wind speed or direction first, then calculate the daily or monthly mean.

Interested in downloading wind data? Please read:
How can I subset and download a large amount of the MERRA-2 data?

Examples of how to calculate or plot wind:
How to calculate and plot wind speed using MERRA-2 wind component data using Python

How to calculate daily mean wind speed using MERRA-2 hourly wind component data with GrADS

How to Create Wind Vector Plots with Panoply