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 | 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 | Direction of combined wind | 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 | 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 | 2 |
scaledValueOfFirstFixedSurface = 1
typeOfSecondFixedSurface = 255 [Missing ] scaleFactorOfSecondFixedSurface = 0 | gridDefinitionTemplateNumber = 0 [Latitude/longitude] |
IndicatorOf UnitOfTimeRange = 1 [Hour] |
| 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 (WMO GRIB2 compliant) | 10 | 0 | 3 |
|
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