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Before seeing the macro code to generate the plot we inspect the file itself we wanted to plot. Double-click on the 'conc_s001.grib' GRIB icon' in folder 'result_fw_conc' to start up the Grib Examiner. We can see that this file contains the "mdc" (=Mass density concentration) fields we want to visualise. We can find out further details about this parameter by setting the Dump mode to Namespace and Namespace to Parameter:
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The macro to visualise the concentration fields on a given level is 'plot_levelconc.mv'.
In the macro first we define the level (8000 m) and the parameter ("mdc") we want to plot. Then we call the Macro Library Function mvl_flexpart_read_hl() to extract the data.
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