## Advanced / Satellite / TOMS Viewer

The viewer for the TOMS Aerosol Index provides a quick and qualitative way to evaluate the model calculation for dust storms, fires, and other events that may inject a significant number of particles into the atmosphere. This is accomplished by overlaying the AI values with the model particle positions from the particle dump file and/or the concentration field. The TOMS display provides a color coded representation of analysis of aerosols from the "Total Ozone Mapping Spectrometer". A range of warmer colors represents various positive values corresponding to absorbing aerosols.

The particle position dump file should have been created during the simulation by configuring the output of particle files (item 9) in the advanced configuration menu. Note that output is only required once-per-day because each TOMS data file represents all the overpasses for one day. For any given longitude, the satellite overpass occurs approximately near solar noon. Therefore the output time should be determined according to the predominant particle longitude. For instance, for the eastern United States, solar noon occurs around 1600 UTC.

The viewer has several input options that can all be selected through the GUI. The map center can be set for the dateline or prime meridians; the AI display has a minimum value below which nothing will be shown; and there is an AI color increment that represents the AI difference between the colors. Colors change from cold (blue) to warm (red) with increasing AI.

The times in the output files are not matched and they are just displayed in time sequence, with the TOMS file opened according to the date-time indicator written in the particle file. Therefore multiple particle or concentration files could be written for each day, but only one TOMS file will be opened for that day.

There are two steps involved in viewing these files. First the map domain needs to be initialization by first clicking and holding the left mouse button from the lower left corner and releasing the button at the upper right corner. The map will then be redrawn. Then each left button mouse click draws next data for the next time period. A right button click will exit the display loop.

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