qscat & grads

[Ted Pollock]

Sorry, I was working with the psi quickscat data. I should have
mentioned that at the top of my last email.

Ted


Quoting "Michael J Murphy" <mjm at HAWAII.EDU>:

> GRADSUSR list,
>
>    I have downloaded a QSCAT data file in  netcdf format and have
> been trying to view the data with GrADS by creating a .ddf (data
> descriptor file) along with using the xdfopen command.  I have read
> though all the GrADS documentation and have been unsuccessful in
> converting the dimensions of the data into a format that GrADS can
> read.
>
>   I have added the contents of an ncdump command I did on the file
> at the end of this email.  As you can see the only dimensions
> specified are time and cross_track cells.  I understand how the file
> is divided up into swaths with a variable for latitude and longitude
> for each swath.  What I don't understand is how to put this
> convention into a .ddf format that GrADS can read.
>
>   I emailed the people who supply the data and they said I should be
> able to open the file by using a sdfopen command.  This has not
> worked however because the .nc file does not appear to be in COARDS
> format (I get an error message about there being no discerable X
> coordinate).  Any advice someone might have with this issue will be
> greatly appreciated.
>
> Thanks,
> MJ
>
>
>
>> ncdump -c QSCAT.2006092.nc
> netcdf QSCAT.2006092 {
> dimensions:
>         time = UNLIMITED ; // (23157 currently)
>         cross_track_cells = 76 ;
>
> variables:
>         long Row_Mean_Time(time) ;
>                 Row_Mean_Time:long_name = "average time" ;
>                 Row_Mean_Time:units = "seconds from 1-1-1999 00:00:00" ;
>                 Row_Mean_Time:actual_range = 228787201, 228873597 ;
>                 Row_Mean_Time:scale_factor = 1 ;
>                 Row_Mean_Time:add_offset = 0 ;
>                 Row_Mean_Time:missing_value = 0 ;
>         short WVC_lon(time, cross_track_cells) ;
>                 WVC_lon:long_name = "longitude" ;
>                 WVC_lon:units = "degrees" ;
>                 WVC_lon:actual_range = 0.f, 359.98999f ;
>                 WVC_lon:scale_factor = 0.0099999998f ;
>                 WVC_lon:add_offset = 180.f ;
>                 WVC_lon:missing_value = 32767s ;
>         short WVC_lat(time, cross_track_cells) ;
>                 WVC_lat:long_name = "latitude" ;
>                 WVC_lat:units = "degrees" ;
>                 WVC_lat:actual_range = -73.68f, 79.919998f ;
>                 WVC_lat:scale_factor = 0.0099999998f ;
>                 WVC_lat:add_offset = 0.f ;
>                 WVC_lat:missing_value = 32767s ;
>         short Wind_Dir(time, cross_track_cells) ;
>                 Wind_Dir:long_name = "wind direction" ;
>                 Wind_Dir:units = "degrees (oceanic convention)" ;
>                 Wind_Dir:actual_range = 0.f, 360.f ;
>                 Wind_Dir:scale_factor = 0.0099999998f ;
>                 Wind_Dir:add_offset = 180.f ;
>                 Wind_Dir:missing_value = 32767s ;
>         short Wind_Speed(time, cross_track_cells) ;
>                 Wind_Speed:long_name = "wind speed" ;
>                 Wind_Speed:units = "m/s" ;
>                 Wind_Speed:actual_range = 0.f, 69.f ;
>                 Wind_Speed:scale_factor = 0.0099999998f ;
>                 Wind_Speed:add_offset = 0.f ;
>                 Wind_Speed:missing_value = 32767s ;
>         byte Rain_Flag_combination(time, cross_track_cells) ;
>                 Rain_Flag_combination:long_name = "rain flag" ;
>                 Rain_Flag_combination:units = "none" ;
>                 Rain_Flag_combination:actual_range = 0s, 1s ;
>                 Rain_Flag_combination:scale_factor = 1.f ;
>                 Rain_Flag_combination:add_offset = 0.f ;
>                 Rain_Flag_combination:missing_value = 255s ;
>                 Rain_Flag_combination:rain_threshold = 1s ;
>         byte Rain_Flag_rad(time, cross_track_cells) ;
>                 Rain_Flag_rad:long_name = "radiometer rain flag" ;
>                 Rain_Flag_rad:units = "none" ;
>                 Rain_Flag_rad:actual_range = 0s, 1s ;
>                 Rain_Flag_rad:scale_factor = 1.f ;
>                 Rain_Flag_rad:add_offset = 0.f ;
>                 Rain_Flag_rad:missing_value = 255s ;
>                 Rain_Flag_rad:rain_threshold = 1s ;
>
> // global attributes:
>                 :build_id = "2.3.2/2000-04-07" ;
>                 :Model_function = "Ku-2001" ;
>                 :sensor_name = "SeaWinds on QuikSCAT" ;
>                 :first_data_time = "02 April 2006 00:00:01" ;
>                 :last_data_time = "02 April 2006 23:59:57" ;
>                 :wind_reference_height = "10m" ;
>                 :history = "Created on 04 April 2006 by COAPS/FSU" ;
>                 :contact_info = "scat_sci at coaps.fsu.edu" ;
>
> data:
> }
>
>
>