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represent overlapping, multiple polygons?

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Hi all,

I'm making a final map of a wild fire. I have several polygons, which show its progression. The only problem being, the final perimeter is smaller (more accurate) than some of the early ones. So it confuses the intent.

The audience is for the fire management people, the purpose to communicate as much info as possible. How would some of you cartographers represent this data?

I think what I might do is drop some of the less significantly changed perimeters and then add a crosshatch or transparency fill to the final perimeter, which I would place under the earlier perimeters.

Attached is an outline of what I'm dealing with, the thick BLUE being the final and most important piece of data. I will probably use either an illuminated relief/generalized land cover or color aerial photo as a base layer.

I'm not sure how I should portray this, or if it is even possible to effectively do so. Any/all advice appreciated :)

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the purpose to communicate as much info as possible. How would some of you cartographers represent this data?

i'd think about doing something dynamic or animated.

Erin John LeFevre

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Rob's suggestion of an animated map would be an excellent way to show the spread and retreat of fire at a certain time. If this isn't an option, then modify what you have. I would remove the date labels and put them in a legend along with the cooresponding symbology. You could also spend some more time refining the boundary symbology so it's more distinct and clear. It would also be much more readable if you took the opacity of the topo down to about 10-15%.

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