ShowCases of Analysis with LAGRANTO

The calculation of trajectories is a common technique for the analysis of atmospheric circulation characteristics. The material presented here is used in the curricula at IfM/FUB. It is maintained in the git-project gitlab@ifm (you will need an account at IfM for access). The tools can handle CCLM-output (clm version 5.x) and ERA5 data as input files. There are three major steps in the workflow and the run_lagranto.sh script will provide these major functions by calling the other tools from the toolbox:

1. Make a new empty folder and create your first configuration file .....
   run-lagranto.sh 1

2. Make a copy and modify the configuration file CONFIGFILE and run the first analysis. The circulation-data will be stored in a cache-folder. (You can setup or rebuild the cache with toolbox-functions.) The result of the analysis is in RESDIR .....
   run-lagranto.sh 2 RESDIR CONFIGFILE

3. Optimize the visualisation and rebuild the figures. This step uses the calculated trajectories .....
   run-lagranto.sh 3 RESDIR CONFIGFILE

For more details about LAGRANTO please have a look at the official Lagranto-Homepage or read the tutorial (Aug/2011). Thank's Michael Sprenger and Annika Oertel for startup support.

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The source code and example configurations

• README more about the examples
• base/ the basic scripts
• tools/ separate functions in the toolbox
• example-rc/ contains showcase configurations using CCLM input data
• README more about the git-project
• The visualisation plugin was written in elm, read more about ... webtools
  inspect the source code ... Main.elm
  use the album parser for the setup of your picture folder ... make_json_picts.py
  place the folder in your own webspace ...
  start or load the your picture-folder-url with the viewer ...
  share the url and discuss the results with your colleagues ...

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Produce a Series of Analyses

The repetion of a single analysis with the same configuration but for a different time window can be automated. In the step 1 you have to define a configuration template. It looks like a normal configuration exept the time informations. Here you have to include place holders, e.g. for Y1=1990 use Y1=%Y1%. The placeholder for the real year is %Y1%. Same procedure works for all date definitions (Y1,M1,D1,H1,Y2,M2,D2,H2). For the name of the result file you should add a date mark, e.g. TRAJ_OUT=RESULT_%Y1%%M1%%D1%%H1%. The file extension should be .template instead of .rc. After setup of the template configuration you have to produce in step 2 the series of configuration files.

The meaning of the command line parameters is

• CONFDIR ... in that folder the configurations will be stored
• TEMPLATE ... the configuration template with all the placeholders
• START, STOP ... the date range for the series in the format YYYYMMDDHH
• DURATION ... the length of the trajectories in hours
• DELTA ... the offset between to trajectory calculations in hours

The result of this step is a series of configuration, which differs in the time window. In the last step step 3 you have to run the analysis with each filtered configuration. This can be done in a loop, like this ...

The results of the series you find in RESDIR. The series of pictures you can prepare for the web visualisization or you can produce a animation, e.g. use ffmpeg. An example is the script make_film.sh.

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Collection of example outputs

• Results of ShowCases with CCLM data ... example-out
• Collection of pictures ... ShowCases created following the .../traj_schowcases/l_all/rc-files/psc-NNN.rc using the educational data set (see table at the end of the page)

  	Description	plotten.rc
  1	use all defaults with North-Atlantic era5-data Jan/2009 data	[ show ]
  2	optimize the picture	[ show ]
  3	use an additional tracer (temperature)	[ show ]
  4	color shows age and radius temperature	[ show ]
  5	color show level and radius temperature	[ show ]
  6	color shows temperature and radius the level	[ show ]
  7	mark the boundary layer with open circles	[ show ]
  8	hide the landscape and make transparent overlay	[ show ]
  9	plot only the landscape as lower picture layer	[ show ]

  You can simply produce pictures from the trajektory file using the plot-tool .../tools/l_all/tools/plotten.py ...

  1. create a configuration file, examples see in the showcase table, and store it into plotten.rc
  2. put the trajectory file and the configuration into one (empty) folder
  3. run the plot-tool in the same folder
• Normal collection of pictures ... album 001
• Collection of pictures with overlay ... album 002 (smaller pictures, faster download)
• Difference due to time resolution of input data (using ERA5) ... album 003

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Please try ...

... following data sets are prepared for LAGRANTO and available in the IfM intranet ...