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====== Getting Ready With The Data ======
* [[atmos:software:lrose:Making the Data Ready For Work|Preparing the Data]]

===== Conversion of IRIS to Mdv Data For Strathmore Radar using LROSE ======
OBJECTIVE:  The **objective** of this work flow is to take archive data provided by Environmental Canada for the Strathmore radar and create MDV formated data files that are viewable by the LROSE Rview application.
  
DATA SET: The summer 2017 Strathomore Radar **data set** was obtained from Environmental Canada and is currently available via [[ftp://transfer1.atmos.und.edu/ftpuser/DavidDelene/Calgary/|ftp]]. 

=== Creating Directories ===
Create the projDir.strathmore directory:
  mkdir ~/projDir.strathmore/
Create subdirectory
  cd ~/projDir.strathmore/
  mkdir CVS data display ingest params scripts system   
Create data subdirectories.
  cd data
  mkdir ascii images mdv NetCdf raw spdb verify 
Create data/raw subdirectories. 
  mkdir ~/projDir.strathmore/data/raw/radar
  mkdir ~/projDir.strathmore/data/raw/radar/strathmore
  mkdir ~/projDir.strathmore/data/raw/radar/strathmore/20170601/

//NOTE: The "20170601" corresponds to the directory of particular day, in this case 1st June 2017, which uses the //**yyyymmdd**// format.//
     
Create DOPVOL subdirectory.
  mkdir ~/projDir.strathmore/data/raw/radar/stathmore/DOPVOL

Create additional data subdirectories.
  mkdir ~/projDir.strathmore/data/NetCdf/radar
  mkdir ~/projDir.strathmore/data/NetCdf/radar/strathmore/
  mkdir ~/projDir.strathmore/data/mdv/radar
  mkdir ~/projDir.strathmore/data/mdv/radar/cart
  mkdir ~/projDir.strathmore/data/mdv/radar/polar/
  mkdir ~/projDir.strathmore/data/mdv/vil/

=== Processing Raw Data ===
Uncompress raw IRIS formatted data files.
  unzip compressed_data.zip -d ~/projDir.strathmore/data/raw/radar/strathmore

//NOTE: The directory //**strathmore**// should be populated with the raw data files.//

Moving Raw Data files into specific directories.
  mv 20000501?*CONVOL* ~/projDir.strathmore/data/raw/radar/strathmore/20000501  
  mv 20000502?*CONVOL* ~/projDir.strathmore/data/raw/radar/strathmore/20000502
..and so on !!
  mv 200005?*DOPVOL* ~/projDir.strathmore/data/raw/radar/strathmore/DOPVOL

=== Converting The Data from IRIS to NetCdf (cfRadial) Format ===

Download the **RadxConvert** params file from {{ :atmos:software:lrose:radxconvert_strathmore_20200318.params |here}}.
  wget --trust-server-names http://wiki.atmos.und.edu/lib/exe/fetch.php?media=atmos:software:lrose:radxconvert_strathmore_20200318.params -O radxconvert_strathmore_20200318.params

//NOTE:  To generate a default params file use the "RadxConvert -print_params > ~/projDir.strathmore/display/params/RadxConvert.params" command can be used.//

Convert a day's worth of data.
  RadxConvert -f ~/projDir.strathmore/data/raw/radar/strathmore/20000501/*CONVOL* -params ~/projDir.strathmore/display/params/RadxConvert.params

Run similar command for all other days of data.

//NOTE: The //**NetCdf/radar/strathmore**// directory should now have all the yyyymmdd directories containing the data in the NetCdf format.//  

=== Convert NetCdf (radial data) to Mdv (cartesian) Formatted Data  ===
Download the Strathmore params files from {{ :atmos:software:lrose:radx2grid_strathmore_20200318.params |here}}. 

//NOTE: An example params file for Radx2Grid can be generated using "Radx2Grid -print_params > ~/projDir.strathmore/ingest/params/Radx2Grid.params"//
    
 Change your directory to:
  ~/projDir.strathmore/ingest/params
  
 Use vi Radx2Grid.params to get inside Radx2Grid.params and make the following changes:
  input_dir = "~/projDir.strathmore/data/NetCdf/radar/strathmore";
  mode = ARCHIVE;
  start_time = "2000 05 01 00 00 00";
  end_time = "2000 07 31 23 59 59";
  output_dir = "~/projDir.strathmore/data/mdv/radar/cart";
  
 Go to command line and run the following:
  Radx2Grid -params ~/projDir.strathmore/ingest/params/Radx2Grid.params
  
This should successfully convert the data from NetCdf to mdv format. The //**data/mdv/radar/cart**// directory should have the **yyyymmdd** directories with the data in mdv format now !!
==== Converting The Data In mdv Format To Generate The vil Also In mdv Format ===

This step is necessary only if your research involves working with **vil**.

The program **Mdv2Vil** is used for this conversion.

 Make sure you are at the following location:
  ~/projDir.strathmore/ingest/params

 Generate the params file for **Mdv2Vil** using the following command from **command line**:
   Mdv2Vil -print_params > ~/projDir.strathmore/ingest/params/Mdv2Vil.params
   
 Run **vi Mdv2Vil.params** to get inside Mdv2Vil.params and make the following changes:
   input_dir = "~/projDir.strathmore/data/mdv/radar/cart";
   mode = ARCHIVE;
   output_dir = "~/projDir.strathmore/data/mdv/vil";
   
 Run the following from the **command line**:
   Mdv2Vil -start "2000 05 01 00 00 00" -end "2000 07 31 23 59 59" -params ~/projDir.strathmore/ingest/params/Mdv2Vil.params

The **data/mdv/vil** directory should now have the **yyyymmdd** directories containing the vil of the data in mdv format.

==== Computing VIL Only Above A Certain Height ====
VIL is a quantity computed throughout the vertical extent of a storm - right from its base all the way up to its top.
 In order to compute VIL only above a certain height, make the following change in the Mdv2Vil params     file:

Under the **min_height** option in the **COMPUTING VIL** section in the params file, 
  min_height = 4;
  
As a result of the above step, Vil would be calculated from a height of 4 km all the way up to the storm top. If min_height = 0, Vil would be calculated from a height of 0 km (basically ground level) to the storm top.

For this project, only Vil above the melting layer is used. The average melting layer height of all the storms studied is a little under 4km. So, the value 4 is chosen in this example.


 



===== Displaying the Radar Data =====

Now that the data is set up, it would have to be displayed using LROSE. For that a symbolic link should be created.

==== Creating Symbolic Link ====
The computer might store data from a number of different radars. LROSE does not know which radar data it should display. Setting a symbolic link is a way of telling LROSE which radar data it should display. If the symbolic link points to the Strathmore data, LROSE would display the Strathmore data. If the symbolic link is made to point to the data from Hogwarts, LROSE would display the Hogwarts data.

To create the symbolic link, make sure you are in the //**yourfirstname.lastname**// directory.

  Then run the following command from terminal:
  ln -s projDir.strathmore projDir  
where, //**projDir.strathmore**// is the directory being pointed at and **projDir** is the name of the symbolic link that has been created.   

 To check if the symbolic link is created, run the following command from terminal:
  ls -l projDir
  
 If the link gets created successfully, the output should be:
  projDir -> projDir.strathmore
  
**NOTE:** The above line may or may not be the only line of output. Other links and directories for which the user has read/write permission would also get displayed. 
  
==== Displaying the Radar Data Using Rview ====
 Now that the link is created, it should be displayed on the Rview window of LROSE by running the following command from terminal:

  Rview -params ~/projDir/display/params/Rview.archive
  
or include start data/time.

  Rview -params ~/projDir/display/params/Rview.archive -time "2017 07 08 12 09 56"