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 file	MARS	Sample file	parameter ( WMO GRIB2 - TABLE 4.2-10-0)	Discipline	Category	Number	Grid	vertical level	time (grib2/tables/2/4.4.table)	Description
Existing Grib1 Data :		Proposed Grib2 Data :
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	Code table4.5 – Fixed surface types and units ?? 102 Specific altitude above mean sea level 103 Specified height level above ground	IndicatorOf UnitOfTimeRange = 1 [Hour]
2			V-component of wind ( 10 m )	0 [ M products ]	2 [ Momentum ]	3
WAVE_229.140_1x1.grb	229.140 Significant height of combined wind waves and swell	WAVE_229.140_1x1.grb2	Significant height of combined wind waves and swell	10 [ O products ]	0 [ Waves ]	3		typeOfFirstFixedSurface = 101 [Mean sea level (grib2/tables/5/4.5.table) ] typeOfSecondFixedSurface = 255		Four times the square root of the integral of wave variance spectrum.
WAVE_231.140_1x1.grib	231.140 Peak period of 1D spectra	WAVE_231.140_1x1.grb2	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
WAVE_230.140_1x1.grib	230.140 Mean wave direction	WAVE_230.140_1x1.grb2	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