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I did notice the correct info in the NetCDF metadata, but a gdalinfo report
has different information. Below is a snippet of that report with the
different values, it may be an issue with the grib driver on gdal's side. I
will continue to investigate.
Driver: GTiff/GeoTIFF
Files: out.tif1
Size is 6, 7
Coordinate System is:
PROJCS["unnamed",
GEOGCS["WGS 84",
DATUM["WGS_1984",
SPHEROID["WGS 84",6378137,298.257223563,
AUTHORITY["EPSG","7030"]],
AUTHORITY["EPSG","6326"]],
PRIMEM["Greenwich",0],
UNIT["degree",0.0174532925199433],
AUTHORITY["EPSG","4326"]],
PROJECTION["Lambert_Conformal_Conic_2SP"],
PARAMETER["standard_parallel_1",0],
PARAMETER["standard_parallel_2",0],
PARAMETER["latitude_of_origin",25],
PARAMETER["central_meridian",0],
PARAMETER["false_easting",0],
PARAMETER["false_northing",0],
UNIT["metre",1,
AUTHORITY["EPSG","9001"]]]
Origin = (-1592.424266064417225,2268.326251018509083)
Pixel Size = (5.079361328124969,-5.079472167968713)
Metadata:
NC_GLOBAL#Conventions=CF-1.0
NC_GLOBAL#Originating_center=US National Weather Service (NCEP) subcenter
= 5
NC_GLOBAL#Generating_Process_or_Model=Forecast
NC_GLOBAL#Product_Status=Operational products
NC_GLOBAL#Product_Type=Forecast products
NC_GLOBAL#cdm_data_type=GRID
NC_GLOBAL#creator_name=US National Weather Service (NCEP) subcenter = 5
NC_GLOBAL#file_format=GRIB-2
NC_GLOBAL#History=Translated to CF-1.0 Conventions by Netcdf-Java CDM
(NetcdfCFWriter)
Original Dataset = NDFD-CONUS_5km_best.ncd; Translation Date = Tue Jan 05
10:22:42 MST 2010
NC_GLOBAL#_CoordinateModelBaseDate=2009-11-21T12:00:00Z
Maximum_temperature#long_name=Maximum_temperature @ height_above_ground
Maximum_temperature#units=K
Maximum_temperature#missing_value=nan
Maximum_temperature#grid_mapping=Lambert_Conformal
Maximum_temperature#GRIB_param_discipline=Meteorological_products
Maximum_temperature#GRIB_param_category=Temperature
Maximum_temperature#GRIB_param_name=Maximum_temperature
Maximum_temperature#GRIB_param_id=2, 0, 0, 4
Maximum_temperature#GRIB_product_definition_type=Average, accumulation,
extreme values or other statistically processed value at a horizontal level
Maximum_temperature#GRIB_level_type=103
Maximum_temperature#GRIB_VectorComponentFlag=gridRelative
Maximum_temperature#coordinates=time2 y x
time2#units=hours since 2009-11-21T12:00:00Z
time2#long_name=forecast time coordinate
time2#standard_name=time
time2#_CoordinateAxisType=Time
y#units=km
y#long_name=y coordinate of projection
y#standard_name=projection_y_coordinate
y#grid_spacing=5.07947216796875 km
y#_CoordinateAxisType=GeoY
x#units=km
x#long_name=x coordinate of projection
x#standard_name=projection_x_coordinate
x#grid_spacing=5.079361328125 km
x#_CoordinateAxisType=GeoX
time1#units=hours since 2009-11-21T12:00:00Z
time1#long_name=forecast time coordinate
time1#standard_name=time
time1#_CoordinateAxisType=Time
Lambert_Conformal#grid_mapping_name=lambert_conformal_conic
Lambert_Conformal#standard_parallel=25
Lambert_Conformal#longitude_of_central_meridian=265
Lambert_Conformal#latitude_of_projection_origin=25
Lambert_Conformal#earth_shape=Earth spherical with radius specified by
producer
Lambert_Conformal#spherical_earth_radius_meters=6.3712e+06
Lambert_Conformal#GRIB_param_Dx=5079.36
Lambert_Conformal#GRIB_param_Dy=5079.47
Lambert_Conformal#GRIB_param_GDSkey=801839731
Lambert_Conformal#GRIB_param_La1=20.192
Lambert_Conformal#GRIB_param_LaD=25
Lambert_Conformal#GRIB_param_Latin1=25
Lambert_Conformal#GRIB_param_Latin2=25
Lambert_Conformal#GRIB_param_Lo1=238.446
Lambert_Conformal#GRIB_param_LoV=265
Lambert_Conformal#GRIB_param_NpProj=true
Lambert_Conformal#GRIB_param_Nx=1073
Lambert_Conformal#GRIB_param_Ny=689
Lambert_Conformal#GRIB_param_ProjFlag=0
Lambert_Conformal#GRIB_param_Quasi=false
Lambert_Conformal#GRIB_param_ResCompFlag=8
Lambert_Conformal#GRIB_param_SpLat=-90
Lambert_Conformal#GRIB_param_SpLon=0
Lambert_Conformal#GRIB_param_VectorComponentFlag=gridRelative
Lambert_Conformal#GRIB_param_Winds=Relative
Lambert_Conformal#GRIB_param_grid_name=Lambert_Conformal
Lambert_Conformal#GRIB_param_grid_radius_spherical_earth=6.3712e+06
Lambert_Conformal#GRIB_param_grid_shape=Earth spherical with radius
specified by producer
Lambert_Conformal#GRIB_param_grid_shape_code=1
Lambert_Conformal#GRIB_param_grid_type=30
Lambert_Conformal#GRIB_param_grid_units=m
Lambert_Conformal#_CoordinateTransformType=Projection
Lambert_Conformal#_CoordinateAxisTypes=GeoX GeoY
AREA_OR_POINT=Area
Image Structure Metadata:
INTERLEAVE=PIXEL
Corner Coordinates:
Upper Left ( -1592.424, 2268.326)
Lower Left ( -1592.424, 2232.770)
Upper Right ( -1561.948, 2268.326)
Lower Right ( -1561.948, 2232.770)
Center ( -1577.186, 2250.548)
Band 1 Block=6x6 Type=Float32, ColorInterp=Gray
NoData Value=nan
Metadata:
NETCDF_VARNAME=Maximum_temperature
...
thanks.
kss
# ===================
Kyle Shannon
Physical Science Technician
RMRS Fire Sciences Lab
Fire, Fuels & Smoke - RWU 4405
5775 Highway 10 W.
Missoula, MT 59808
(406)646-6577
kshannon@xxxxxxxxx
ksshannon@xxxxxxxxx
# ===================
On Tue, Jan 5, 2010 at 11:19 AM, Robb Kambic <rkambic@xxxxxxxxxxxxxxxx>wrote:
> On Tue, 5 Jan 2010, Kyle Shannon wrote:
>
> Hello all,
>> I am using the unidata thredds server to download some NDFD data. I
>> noticed that
>> the projection specified is a Lambert_Conformal_Conic_2SP and both
>> standard
>> parallels are specified as 0. In the metadata, if I am reading it
>> correctly, the
>> projection is actually a Lambert_Conformal_Conic_1SP with a standard
>> parallel of
>> 25. I am using GDAL to hangle the files and proj4 has trouble with the
>> 1st
>> scenario, but not the second. Is the projection set at the source (NOAA
>> NDFD) or
>> by the NetCDF subsetting service? Who can I contact to deal with this
>> issue?
>> Thanks.
>>
>
> Kyle,
>
> The projection information is obtained from the data, so the source is NCEP
> NDFD. The NCEP Lambert conformal projection is described at:
> http://www.nco.ncep.noaa.gov/pmb/docs/grib2/grib2_temp3-30.shtml
>
> Included is the GDS information from today's 12Z NDFD file and the
> standard parallels are set to 25 not 0.
>
> I will check that the subsetting service is getting the information
> correctly.
>
> Robb...
>
>
> GDSkey = 801839731
> grid_type = 30
> grid_name = Lambert_Conformal
> grid_shape_code = 1
> grid_shape = Earth spherical with radius specified by producer
> grid_radius_spherical_earth = 6371200.0
> Quasi = false
> Nx = 1073
> Ny = 689
> La1 = 20.192
> Lo1 = 238.446
> ResCompFlag = 8
> Winds = Relative
> VectorComponentFlag = 1
> LaD = 25.0
> LoV = 265.0
> Dx = 5079.3613
> Dy = 5079.472
> grid_units = m
> ProjFlag = 0
> NpProj = true
> Latin1 = 25.0
> Latin2 = 25.0
> SpLat = -90.0
> SpLon = 0.0
>
>
>
>
>
>> kss
>>
>> # ===================
>> Kyle Shannon
>> Physical Science Technician
>> RMRS Fire Sciences Lab
>> Fire, Fuels & Smoke - RWU 4405
>> 5775 Highway 10 W.
>> Missoula, MT 59808
>> (406)646-6577
>> kshannon@xxxxxxxxx
>> ksshannon@xxxxxxxxx
>> # ===================
>>
>>
>>
>
> ===============================================================================
> Robb Kambic Unidata Program Center
> Software Engineer III Univ. Corp for Atmospheric
> Research
> rkambic@xxxxxxxxxxxxxxxx WWW:
> http://www.unidata.ucar.edu/
>
> ===============================================================================
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