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Extracting a dataset from GFS GRIB


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Posted
  • Location: London
  • Location: London

    Hallo,

     

    Is there any guidance on how one should go about extracting wind velocity vectors from an upper air dataset contained in an historical GFS GRIB over a given region? I have access to a copy of Matlab and should prefer if the raw data could be output to an Excel file if it's possible.

     

    Would appreciate any tips.

     

    Thanks.

     

    Weirp

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    Posted
  • Location: Pendlebury, Salford
  • Location: Pendlebury, Salford

    The Wind dataset in a GRIB file should be stored as 'U' and 'V' components.

     

    Extracting the Speed is then SQR(U^2 + V^2)

     

    Extracting the Direction a bit more complex:

     

    (180 / PI) * ATN( U / V)

     

    But then adjust the angle relative to North as follows:

     

    If V > 0 Add 180

    if U>0 and V<0 Add 360

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