How to rotate a map ? (ArcMap 10.1)

[DiederikD_Hert]

Hello

I am afraid I need some help. I am a complete newbee, and right now I am stuck.

What do I want ? A map of the Southern Hemisfere (South Pole Orthographic projection), but with another meridean pointing to the north (not the Greenwich), for instance the 15°W.

What have I done/tried already ?
I started from the basemap_continents file. I used project 'Data Managment' to make a South Pole Orthographic transformation. I made a layer file from it. When I open that new .lyr file in an new ArcMap Document, I see the Southern Hemisfere with Antarctica in the Middle, but the Greenwich Meridean is pointing to the North.
I then tried to change several things while making the transformation (false easting, northing, longitude/latitude of center) but that doesn't gave me the desired result. I read I should try to change the Prime Meridean, but it doesn't affect anything at all (unless I do it in a wrong way). The Geographic Coordinate system should stay GCS_WGS_1984 (because otherwise other data will not be projected correctly).

Can anybody tell me how I can get the desired result (step by step, because I am a complete newbee) or help me create such a layer (but I would prefer telling me how to do it, so I can do it for myself in future).

Thanks for any help.

Diederik

[MelitaKennedy · Accepted solution]

Hi Diederik,

I think you should choose one of the existing Antarctica-based projected coordinate systems. As an example, I'll use UPS South. The definition is located in projected coordinate system, polar.

In ArcMap, open data frame properties (right click in the map and select properties from the context menu OR right click Layers in the table of contents and select properties).

Select the Coordinate System tab.


If using 10.1,
   1. Type in UPS in the search box, then open the resulting folders to find UPS South. Select it.
   2. Right click UPS South and click "copy and modify".


If using 10.0,
   1. Browse the folders to the Polar group and select UPS South.
   2. Click the Modify button.

Next steps are the same for either version.

   3. Change the central meridian value to -15 or whatever longitude value you want to have pointing up. You may also want to change the projected coordinate system name so that it's clear that it's a custom definition. OK all dialogs.

All data layers that have correctly defined coordinate systems will get projected on-the-fly (in memory) to this coordinate system. If you want to convert data permanently to this coordinate system, use the Project Tool, or right click a layer in the map and choose data, export data. In that dialog, use the data frame's coordinate system.

Melita

[DiederikD_Hert]

Melita,

Thanks for your answer. It worked, thanks.
A friend of mine was convinced that I could obtain that result simply by changing the longitude of center to -15. Although I am sure I had tried that before with no succes, I retried it, and now it gave the desired result. Strange, but it doesn't matter.

I have two solutions now :).

Sincerely
Diederik