NOTE: The galeon mailing list is no longer active. The list archives are made available for historical reasons.
I am pleased that this has raised this question of Gaussian grids! We have rectified the grid in X-Y for our datasets, but we have abused the describeCoverage XML to explain the Z dimension as follows
And, not sure if this is the same issue, rotated grids? Grids like #203 and also RUC2 grid #252. No where near monotonic for lat and lon and typically the only georeference information given is a reference lat/lon and reference lon as below: lat1: 16.281
lon1: 233.862 lov: 265.000 RUC2 #252:rec 1:0:date 2005062312 VGRD kpds5=34 kpds6=105 kpds7=10 levels=(0,10) grid=252 10 m above gnd anl:
VGRD=v wind [m/s]
timerange 0 P1 0 P2 0 TimeU 1 nx 301 ny 225 GDS grid 3 num_in_ave 0 missing 0
center 7 subcenter 0 process 105 Table 2
Lambert Conf: Lat1 16.281000 Lon1 233.862000 Lov 265.000000
Latin1 25.000000 Latin2 25.000000 LatSP 0.000000 LonSP 0.000000
North Pole (301 x 225) Dx 20.318000 Dy 20.318000 scan 64 mode 8
min/max data -12.4 12.2 num bits 8 BDS_Ref -124 DecScale 1 BinScale 0
Regridding is fine, but the preference is to maintain the integrity of the
data in its original form.
<RangeSet>
<description>0.09999999403953552 0.19999998807907104 0.30000001192092896 0.5
0.699999988079071 1.0 2.0 3.0 5.0 7.0 10.0 20.0 30.0 50.0 70.0 100.0 150.0 200.0 250.0
300.0 400.0 500.0 600.0 700.0 850.0 975.0 1000.0 </description>
<name>bands</name>
<label>Pressure (hPa units) Levels</label>
<axisDescription>
<AxisDescription>
<name>bands</name>
<label>Bands/Channels/Samples</label>
<values>
<singleValue>1</singleValue>
<singleValue>2</singleValue>
<singleValue>3</singleValue>
<singleValue>4</singleValue>
<singleValue>5</singleValue>
<singleValue>6</singleValue>
So that when you use the kvp BANDS then the client by indexing into the
space-separated description list can calculate which physical level this
corresponds to.
This is not an ideal solution, and I welcome comments on how we can go
about changing this. Rectifying the grid to evenly spaced means a
change to the original dataset (though it is necessary to make geotiff).
Hopefully this will be something that we can push into the GML in
JPEG2000 coverage format.
Norman
-- Rob Cermak : 907-474-7948 : FAX 907-474-7204 : PGP = 0x75869A6EAlaska Ocean Observing System : Data Management School of Fisheries and Ocean Sciences : University of Alaska Fairbanks
cermak@xxxxxxxxxxxx : fnjrc1@xxxxxxx ED9U1M7P01@xxxxxxxxxx : cermak@xxxxxxxxxx
galeon archives: