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[LevelII #TJW-252571]: DATA LEVEL II NEXRAD at DENVER

> Dear Jeff:

Hello Daniel, 

> 
> Many thanks for your fast reply.
> I'm really impressed by your high quality level response. CONGRATULATIONS.

Thank you ;)

> 
> Please let me know if these links to the files are permanent or temporary.

They are permanent, you can download them at your leisure.


> If they are permanent I will copy to my local hard drive the data as I will 
> need (3 radars for this period at Level II data is quite an amount of data 
> for the beginning). If they are temporary I will copy all and allow you to 
> remove the links.
> 
> Thank you also for the Level III data. They will be of extremely help to 
> compare my results against and be sure I am not making any mistake in the 
> Level II data manipulation.
> 

Great, thought they may be of use to you.

> Thank you for the link to the documentation.
> Unfortunately I have already explored this site and I didn't find help on 
> them.
> 
> My doubts are for instance:
> 
> 1) Dimensions and differences between the values SPULSE and  LPULSE of the 
> file header and the value PULSE_WIDTH in the RAY headers.
> I have found in some spec documentation that the nominal pulse width is 1.57 
> µs (short pulse); 4.5 µs (long pulse) ± 4% Are SPULSE and LPULSE the real 
> pulse duration (in miliseconds???) for short and long pulses?
> Is there any header specifying which is used in a particular volume (rule for 
> using short or long)?
> 
> 2) These SPULSE and LPULSE values seems to be in contradiction with the  
> PULSE_WIDTH recorded for any ray and any sweep (in miliseconds????).
> Which is the real value used for the volume measurements?
> 
> 2) The beam width that appears in the headers (0.5 degrees for the super 
> resolution sweeps and 1.0 degrees for the rest) are nominal or the true 
> values?
> I have seen in some NEXRAD documentation that the real one-way 3 dB beam 
> width is 0.96° at 2.7 GHz and 0.88° at 3.0 GHz, so none of the header values 
> are true?
> 
> 3) In the super resolution mode, they are really using a beam width of 0.5° , 
> as the headers suggest, or this just means that the azimuth sector of these 
> rays is 0.5° (but not the real beam width)?
> (how the beam width can vary if the antenna and the frequency are the same 
> for the different sweeps?).
> 
> I'm not sure if you, or your internal staff that write radar readers, can 
> help me with that doubts (the documents on the mentioned webpage didn't 
> helped, or I was unable to use them conveniently).
> But in any case if you can guide me to contact some expert people that could 
> solve these doubts I will be extremely grateful.


I have forwarded this part of the support ticket to our IDV head developer, 
Yuan Ho. Yuan has done much work
on the level II radar readers we use so hopefully he can add some insight to 
your questions.


> 
> Again many thanks for your extraordinary response and for your help.
> 

We are glad you have found the data you need, we will stay in contact regarding 
the radar documentation and best wishes for your science and research.


> Warm regards
> 
> Daniel
> 

Cheers, 

Jeff
Jeff Weber
Unidata User Support
http://www.unidata.ucar.edu

Ticket Details
===================
Ticket ID: TJW-252571
Department: Support IDV
Priority: High
Status: Open