Method one: set appropriate variables. For example (try running this from the shell):
(depending which locale settings you need you may want to set other variables, type "locale" to see the complete list)
If it works, you can wrap it as shell script (just save such line as sth like "myterm", make it executable and puth somewhere in the PATH) and just use "myterm" to spawn new terminals.
Method two: you can use similar trick inside gnome-terminal configuration. Enter profile preferences (Edit/Profile Preferences), click [x] Run a custom command instead of my shell, and use sth like
as your custom command. /path/to/mybash should be executable and contain
(or sth similar) Note that this is "per-profile", so if you use multiple terminal profiles, you may need to repeat it.
PS If you need multiple encodings, just create multiple profiles and use appropriate one whenever you need. Note that you can use
to spawn specific profile from the shell (or from desktop icon or from toolbar icon or ...)