The model prints on a large scale (all of Europe), while the concentration area itself is sometimes rather small. Is it perhaps possible to reduce the scale of the map?

There are two concentration display programs associated with the most recent PC version of Hysplit, each treats the display size differently.

Wincplot – the screen display program. This program always plots the entire domain of the concentration grid, regardless of the size of the plume. To reduce the map size you need to reduce the concentration grid span. From the concentration setup widget, go to “Pollutant, Deposition, Grids Setup”, then to “Grids”, and then under the “Span” entry change the latitude, longitude span of the grid to cover a smaller area.

Concplot – the postscript display program. This program automatically scales the size of the map to keep the map the same over all time periods. To have a finer scale map that corresponds to only one time period you should output only that one time period. You can also run the program from the command line (a DOS window) and set the size argument on the command line to 1. Execute concplot without arguments to get the argument list. There are no options through the GUI to modify the command line. You can modify the tcl script that calls concplot to add any of the optional arguments.