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> Hi Yuan, > I've encountered another problem - unrelated to plotting wave directions. > Like the wave direction data, it also concerns some files from > USGOSAE.org for data from the FNMOC WAVEWATCH III model. > Files that I down loaded for the HEIGHT of wind waves (meters) were > coming up as mean wave PERIOD of wind waves (seconds). I checked with > the folks at USGODAE (see the email thread below) and they confirmed > that the data is good. It appears that there's a problem when IDV goes > to some table to retrieve the data type. > From : http://www.wmo.int/pages/prog/www/WDM/Guides/Guide-binary-2.html > 102 Significant height of wind waves m > > 103 Mean period of wind waves s > > > It appears IDV mistakenly thinks that 102 = Mean period of wind waves. > Alan, Let me know if you get the table and need help. Yuan > Can you confirm this? > My goal here is to plot those wind wave directions on top of the wind > wave height, but I'd like to do that with height in feet. It's hard to > convert seconds to feet :), much easier to convert meters! > > thanks, > alan > > Here's a data file: > > http://www.usgodae.org/ftp/outgoing/fnmoc/models/ww3/2009/2009110800/US058GOCN-GR1mdl.0110_0240_00000F0RL2009110800_0001_000000-000000wnd_wav_ht > > > > > -------- Original Message -------- > Subject: [GODAE #10505]: Problem with FNMOC WW3 data > Date: Fri, 15 Apr 2011 11:09:39 -0700 > From: GODAE Help <address@hidden> > Reply-To: GODAE Help <address@hidden> > To: <address@hidden>, <address@hidden>, > <address@hidden>, <address@hidden>, > <address@hidden>, <address@hidden>, > <address@hidden>, <address@hidden> > > > > I stand corrected. IDV does read in GRIB files. I had to rename it first to > give a .grib extension. Afterwards, it read it in, and plot it. Yes, it > claims for it to be mean_period_of_wind_waves@surface, which is not correct. > > I think you should ping on the IDV group. > > THanks, > Mike > > > Hi Alan: > > > > The data in question appears to be correct as hosted on USGODAE. The > > parameter ID in the GRIB file is 102 which maps to 'significant height of > > wind waves' according to the WMO GRIB specifications. I looked at the > > exact file that you referenced below. > > > > IDV does not read in GRIB data directly. You must be doing some type of > > conversion of the file, perhaps into another format like NetCDF for IDV to > > use it. I am using version 2.9 of the IDV, perhaps there is a newer one > > that can use GRIB directly. > > > > I am going to close off the ticket, since I believe that the data is ok. > > But, feel free to respond back, re-openening it if you feel otherwise. > > > > > > Thanks, > > Mike Frost > > > > > Hello again, Efren, > > > I've attached a copy of a plot I made this morning, with a color scale > > > similar to your's. > > > I think that they're basically the same plot. > > > From the legend, you can see that IDV thinks I'm plotting mean period > > > for wind waves. It must be getting that info from some file header. > > > The Max value on the plot is 4.9 seconds, an appropriate value for wind > > > waves. > > > I tried some other files from this and other days (including from 2010) > > > and they all display as wave period, not height. The max values were > > > always in the range of 4-5 seconds. > > > > > > Just to be sure we're looking at the same file, here's the url for the > > > data file: > > > > > http://www.usgodae.org/ftp/outgoing/fnmoc/models/ww3/2009/2009110800/US058GOCN-GR1mdl.0110_0240_00000F0RL2009110800_0001_000000-000000wnd_wav_ht > > > > > > A couple more observations: > > > The file size for the wind wave height is double that for the wind wave > > > period. Is that significant? > > > Contours for wnd_wv_per and wnd_wv_ht are nearly identical - not > > > unexpected, but a little curious. > > > > > > alan > > > > > > On 4/14/2011 5:20 PM, Serra, Mr. Efren, Contractor, Code 7542 wrote: > > > > Alan, > > > > > > > > [serra@nrlgodae1 2009110800]$ wgrib -V > > US058GOCN-GR1mdl.0110_0240_00000F0RL2009110800_0001_000000-000000wnd_wav_ht > > > > rec 1:0:date 2009110800 WVHGT kpds5=102 kpds6=1 kpds7=0 levels=(0,0) > > grid=240 sfc anl: bitmap: 30390 undef > > > > WVHGT=Sig height of wind waves [m] > > > > timerange 0 P1 0 P2 0 TimeU 1 nx 360 ny 181 GDS grid 0 > > num_in_ave 0 missing 0 > > > > center 58 subcenter 0 process 110 Table 3 > > > > latlon: lat -90.000000 to 90.000000 by 1.000000 nxny 65160 > > > > long 0.000000 to -1.000000 by 1.000000, (360 x 181) scan > > 64 mode 128 bdsgrid 1 > > > > min/max data 0 4.92 num bits 16 BDS_Ref 0 DecScale 4 BinScale 0 > > > > > > > > [serra@nrlgodae1 2009110800]$ > > > > > > > > Above is output from wgrib. I was wondering how you determined that > > it was wind wave PERIOD. Also, I used grib2ctl.pl, gribmap, and gradsc and > > displayed the field. Image attached. > > > > > > > > > > > > Efren A. Serra (Contractor) > > > > DeVine Consulting, Inc. > > > > Naval Research Laboratory > > > > Marine Meteorology Division > > > > 7 Grace Hopper Ave., STOP 2 > > > > Monterey, CA 93943 > > > > Code 7542 > > > > Office: 831-656-4650 > > > > -----Original Message----- > > > > From: address@hidden [mailto:address@hidden] > > > > Sent: Thursday, April 14, 2011 2:50 PM > > > > To: Frost, Mr. Michael; Cook, Mr. John; Ignaszewski, Mr. Mark, Code > > 7542; Cummings, Dr. James; Serra, Mr. Efren, Contractor, Code 7542; > > Karengin, Mr. Dean, Contractor, Code 7501.1 > > > >Subject: [GODAE #10505]: Problem with FNMOC WW3 data > > > > > > > > Sender: address@hidden > > > > Date: Thu Apr 14 21:49:55 UTC 2011 > > > > > > > > Message > > > > Hello, > > > > I recently down loaded some files that were supposed to be wind wave > > HEIGHT data. Instead, they had wind wave PERIOD date. I think the entire > > model run is corrupted like this. > > > > > > > > Is it possible to get the correct data? > > > > > > > > Here's the first file of the series(cl) > > > > > > US058GOCN-GR1mdl.0110_0240_00000F0RL2009110800_0001_000000-000000wnd_wav_ht > > > > > > > > thanks, > > > > Alan Bol > > > > > > > > > > > > > > > > > > > > DEBUG INFO > > > > > > > > remote addr 128.117.107.155 > > > > remote host 128.117.107.155 > > > > remote ident > > > > remote user > > > > request method POST > > > > referer http://www.usgodae.org/contacts.html > > > > user agent Mozilla/5.0 (Windows; U; Windows NT 6.1; en-US; > > rv:1.9.2.16) Gecko/20110319 Firefox/3.6.16 > > > > > > > > > > -- > > > Alan Bol > > > Project Lead | Scientist | Instructional Designer > > > The COMET Program | www.comet.ucar.edu > > > 303.497.8334 voice | 8491 fax > > > > > > > > > Ticket Details =================== Ticket ID: GZO-896323 Department: Support IDV Priority: Normal Status: Closed