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Elle basic

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Basic elle tutorial

This workflow will convert a single raw radar file to the CfRadial format and estimate the surface rain rate. Note, the current parameter files are currently optimized to work on Unix systems. This workflow is one way to test that the applications have been installed properly.

For more information, refer to the following pages on how LROSE calculates KDP, estimates the dominant PID category, calculates rain rates, and estimates the surface precipitation rate.

Run each program one by one on the command line

  1. Download the elle_basic.tar.gz file
  1. Extract contents into the desired directory
tar -zxvf elle_basic.tar.gz

You'll end up with a directory structure that includes files to set environment variables, data required to run some of the programs, the raw radar file, and a sample script that will run all the programs in one go.

Elle basic ls.png

  1. In /elle_basic/env_dirs, edit the directories (note: there is purposely no slash at the beginning of PROJ). Together, HOMED/PROJ should direct you to the elle_basic directory. RAW is the full path to the raw radar data in /elle_basic.
export HOMED="/path/to/home/directory"
export PROJ=“short/path/to/elle_basic”
export RAW="/path/to/elle_basic/raw"
  1. Set the variables in the terminal and set the date. Print out the directory structure to make sure it's pointing to the right directory.
source env_dirs
source env_vars
export days=“20170602”
echo $HOMED/$PROJ
  1. Convert the raw file to a CfRadial file
/path/to/RadxConvert -params ./params/RadxConvert.* -f $RAW/$RADAR_NAME/$days/*.raw*
  1. Run RadxRate to calculate Kdp, the PID, and various rain rates
/path/to/RadxRate -params ./params/RadxRate.* -f ./convert/$RADAR_NAME/$days/*.nc
  1. Run RadxQpe to estimate the near-surface rainfall using the hybrid method
/path/to/RadxQpe -params ./params/RadxQpe.* -f ./rate/$RADAR_NAME/$days/*.nc
  1. In the elle_basic directory, you should now see 3 new directories: convert, rate, and qpe. You can look through the the files in those directories to inspect the new files and check the quality of the data.

Run programs from a sample script

  1. Follow steps 1-3 from the section above.
  1. Edit directories in run_radx.sh script (lines 3 and 12)
cd /PATH/TO/elle_basic
rdir="/PATH/TO/lrose/bin"
  1. Make the file executable, if it isn't already
chmod u+x run_radx.sh
  1. Run shell script/li>
./run_radx.sh
  1. In the elle_basic directory, you should now see 3 new directories: convert, rate, and qpe. You can look through the the files in those directories to inspect the new files and check the quality of the data.

Example output

Shown below are some HawkEye snapshots of data from the files created during each step. Example of the reflectivity field displayed in HawkEye created by RadxConvert.

To run the HawkEye dmg, use the following command and then select files in the File menu:

/Applications/HawkEye.app/Contents/MacOS/HawkEye -params /path/to/elle_basic/params/HawkEye.params.gen

Radxconvert dbz.png

Example of the Kdp field displayed in HawkEye created by RadxRate.

Radxrate kdp.png

Example of the hybrid rain rate field displayed in HawkEye created by RadxRate.

Radxrate hybrid low.png

Example of the estimated surface rain rate field displayed in HawkEye created by RadxQpe.

Radxqpe hybrid.png