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Time Zone Symbology

February 03 2009 | 3 comments
Categories: Symbology

I have been requested to put a time zone layer in one of my maps. I am using the ESRI time zone dataset. Is there anyway to represent the time as clocks? For example I would like to show what time it would be on the east coast if the first time zone was at noon?

something similar to this image
http://www.classbrain.com/artstate/uploads/us-time-zones.jpg

Any ideas?

Mapping Center Answer:

We did something like this using cherubs blowing the wind in different directions to show auxillliary wind direction to be used on historical looking maps.  In fact, the cherub symbols are shown in and article that we wrote called "Achieving Historical Map Effects with Modern GIS". The reference is listed on the Other Resources page here on Mapping Center.

You could do something similar using clock faces.  You can make your own clock face symbols, save them as .emfs, and insert them onto the page layout. To test this out, I Googled "clock face", found a free downloadable template, inserted it as a picture in an ArcMap document, added lines with arrows to indicate the hour, and saved it as an .emf.  I could then insert it on the page layout.

Be sure to use the focussed data frame if you want the symbols to stay in the same place geographically (see the blog entry on "The State of Data Frames" if you don't know about this option.)

Windy cherubs posted by Aileen Buckley on Feb 3 2009 5:31PM
By the way, the windy cherubs are available form download from Mapping Center -- they are in the esri_141.ttf that is in the Historical_Style_fonts folder in the ESRI_Historical_Style on the ArcGIS Recources->Styles page.
Thank you so much!! posted by Jonathan W on Feb 4 2009 11:38AM
I used a clock face as the background. Then I used the same point layer twice (one to represent the hour hand, one for the minute hand).

To get the angles for the hour hand I calculated a new field:
positive numbers
(([ZONE])/12)*360
negative numbers
(([ZONE]+12)/12)*360

and for the minute hand field
positive numbers
(([ZONE]*100)mid100)*36
negative numbers
(([ZONE]*-100)mid100)*36
Wonderful tip! posted by Aileen Buckley on Nov 29 2010 6:18PM
Thanks for the info on how to add this attribute value!

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