At any time, you can change the time zone in Outlook so that it matches your current geographic location.
Changing the time zone in Outlook is the same as changing it in the Windows Control Panel, and the change is reflected in the time displays in all other Microsoft Windows-based programs.
The second time zone is used only to show a second time bar in Calendar view, and does not affect the way in which Calendar items are stored or displayed.
The start and end times for items in the Outlook Calendar are saved in the Coordinated Universal Time (UTC) format, an international time standard similar to Greenwich Mean Time. In both cases, the meeting is saved as starting at the same UTC time of P. If two time zones are shown, the meeting organizer's time zone is used as the reference point.
While having the clock off may not sound like a big deal, it can lead to all sorts of frustrating issues, from some apps not working, to an inability to install OS X due to verification errors, to “connection not private” errors in web browsers, to a variety of other nuisances.