Wave verification GRIB data

Aim of this page :

a table with NCEP data: GRIB sample (only one message and one parameter), encoding explained (not only parameter we need to have all the significant descriptions including the geography)
A table with what we aim to have from the partners. Description in words, GRIB2 coding (not only parameter also all other relevant coding details), possibly an example of grib for each parameter
A common description of the grid we are going to ask the users. We said that this is going to be a global domain. I think we also need a bitmap.

After talking with  Jean Bidlot  we concluded that what we are asking our contributors for in GRIB2 language is :

Sample	MARS	parameter ( WMO GRIB2 - TABLE 4.2-10-0)	Discipline	Category	Number	Grid	vertical level	Description
1		U-component of wind ( 10 m )	0 [ M products ]	2 [ Momentum ]	2	. regular lat-long grid . grid spacing free for the contributor to chose . not need to be global . bitmap ?	Code table4.5 – Fixed surface types and units ?? 102 Specific altitude above mean sea level 103 Specified height level above ground
2		V-component of wind ( 10 m )	0 [ M products ]	2 [ Momentum ]	3
3		Significant height of combined wind waves and swell	10 [ O products ]	0 [ Waves ]	3		?? typeOfFirstFixedSurface = 1 [Ground or water surface] 101 Mean sea level	Four times the square root of the integral of wave variance spectrum.
4		Peak wave period	10 [ O products ]	0 [ Waves ]	34			Reciprocal of the frequency corresponding to the peak of the wave frequency spectrum.
5		Mean zero-crossing wave period	10 [ O products ]	0 [ Waves ]	28			Mean wave period based on the second moment of the frequency spectrum
6	230.140 Mean wave direction	Direction of combined wind waves and swell	10 [ O products ]	0 [ Waves ]	14			Mean wave direction derived from the vector mean direction from the wave variance spectrum.

NCEP sample file  multi_1.glo_30mext.t00z.f000.grib contains:

parameter Name

Discipline

Category

parameter
Number

vertical level

(grib2/tables/2/4.5.table)

horizontal grid

time

(grib2/tables/2/4.4.table)

bitmap

file

u-component of wind

_{(WMO GRIB2 compliant)}

0

2


typeOfFirstFixedSurface = 1 
[Ground or water surface]

scaledValueOfFirstFixedSurface = 1

typeOfSecondFixedSurface = 255 [Missing ]

scaleFactorOfSecondFixedSurface = 0

gridDefinitionTemplateNumber = 0 [Latitude/longitude]
latitudeOfFirstGridPoint = 90000000
longitudeOfFirstGridPoint = 0
latitudeOfLastGridPoint = -77500000
longitudeOfLastGridPoint = 359500000
iDirectionIncrement = 500000
jDirectionIncrement = 500000

IndicatorOf

UnitOfTimeRange = 1 [Hour]



bitMapIndicator = 0 
[A bit map applies to this product]

ucomp.grib2

v-component of wind

_{(WMO GRIB2 compliant)}(grib2/tables/2/4.2.0.2.table)

0

2

3

vcomp.grib2

Significant height of 
combined wind waves and swell

_{(WMO GRIB2 compliant)}

10

0

3

height.grib2

WMO tables :

http://www.nco.ncep.noaa.gov/pmb/docs/grib2/grib2_doc.shtml

http://www.nco.ncep.noaa.gov/pmb/docs/grib2/grib2_table4-2-10-0.shtml

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Wave verification GRIB data