Yes. You can do this multiple ways.

One way would be to set a variable on world start and count down from there, or record the world's time and compare it every so often with the closing date. Though there's probably a lot of better alternatives like reading a file from outside of the game, or something. I'm sure someone else will detail a really great method for this later in the thread.

I'm not really sure if things like this are suited in either Design Philosophy or Developer How-To. But I guess it could fit in both.