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Simple map outlines in lat/long

Posted: Sun Jun 13, 2004 4:56 pm
by Dave Barber
For my own personal use and diversion, I develop and use programs for the MAC to display surface and upper-air data and do analyses of the data. I need map backgrounds that have points given in lat/long so I can display them with my data/analyses in whatever projection I choose. Outlines of the U.S., the states, together with Mexico, Canada, and the Caribbean would be most useful to me. Other areas would be useful/interesting. I've had a hard time finding such files on the internet with the exception of a partial state outline map on a Census Bureau site. Does anyone know of a source?
Dave

Posted: Tue Jun 15, 2004 8:42 am
by Tim Vasquez
I'm not sure if you tried Digital Atmosphere for this but it does have the capability to draw graticules (I think that's the feature you are referring to). Or were you asking that they be labelled with values?

Mapping stuff is definitely a poorly covered area of software... it's either el-cheapo programs or ESRI (aka Arcview et al) which has a monopoly on the software and even much of the data.

Tim

Map backgrounds

Posted: Wed Jun 16, 2004 4:20 pm
by Dave Barber
Tim,
Thanks for the reply. I didn't make myself very clear. I want to be able to draw map backgrounds on my own maps by connecting points for which I have computed screen coordinates from the latitude and longitudes of points on geographic features. That is, I need, for example, an outline of the United States given as a sequence of latitude/longitude pairs. I can then convert these to points on the screen using appropriate map projection equations for a chosen projection, scale, and center point of the map. I can then use the outline as background for the plots and analyses I do in my own programs.

I have obtained one such file from a US Census Bureau site but because it was intended for census related purposes it doesn't even have the northern shores of the Great Lakes and of course none of Canada or Mexico is covered. It does have outlines for all of the states, so it is a help.
I have created such files for myself by manually digitizing from paper maps, but it is very arduous! And because of the effort involved, my maps are somewhat crude and limited in extent.
Dave B

Posted: Wed Jun 16, 2004 7:33 pm
by Tim Vasquez
You may want to try the MWDB (Micro World Databank):
http://www.ngdc.noaa.gov/seg/cdroms/Eco ... /mw/mw.htm

Tim