MERRA-2 Data

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MERRA-2 is a new version of the popular MERRA dataset modelled and distributed by the Global Modeling and Assimilation Office of NASA / Goddard Space Flight Center. The original MERRA dataset will be discontinued sometime in 2016 at which point MERRA-2 will continue to be updated. MERRA-2 uses a newer version of the modelling system and also incorporates newer data sources and observations.

Resolution and Coverage

The model grid is 0.5 degree latitude and 0.625 degree longitude. This is slightly different from the original MERRA dataset.
It holds 1 hourly values in a period from 1992 until present.
Coverage is global for land-areas and coastal regions.
Offshore coverage is only to be expected up to approximately 300 km from the coastline.

Example of MERRA-2 mean wind speeds at 50 m. Screen shot from http://www.windprospecting.com/

Data Availability

MERRA-2 data is commonly available within windPRO with a time-lag of 1-2 months. This is due to the processing time of the data at NASA and the subset-processing at EMD. When the data have been processed at EMD, then the following parameters are available from within the online-data services within windPRO. Please note that the displacement height is the height at which the log wind profile projects the wind to be zero.

Table: Overview of MERRA-2 Dataset Parameters.
Parameter Description
time UTC time stamp
psfc Surface pressure
msl Mean Sea Level pressure
wSpeed.50 Wind speed at 50 m above surface
wDir.50 Wind direction at 50 m above surface
wSpeed.850hpa Wind speed at 850 hpa
wDir.850hpa Wind direction at 850hpa
temperature.10 Temperature at 10 m above surface
temperature.50 Temperature at 50 m above surface
dispHeight Displacement height
precIceWater Total precipitable ice water
precLiqWater Total precipitable liquid water
precWaterVapor Total precipitable water vapor
specHumidity.10 Specific humidity at 10 m

External Links

Acknowledgement

Credits: The Global Modeling and Assimilation Office (GMAO) for the MERRA-analysis and the GES DISC for the dissemination of MERRA.