dIBBSY1000,
Well, I am not too pessimistic as I believe movements such as
the Transition Towns will enable a return to more local living.
Provided we can keep a significant amount of electricity generation
going, we should be able to continue most functions that we have
in our towns, but cities might be a problem.
Maintaining systems such as the internet may not be possible.
Local phone systems will probably continue indefinitely.

If you look at what survived the fall of Rome, you can see that some
of our advances will also survive. The telephone being one of them.
All this is why I say worrying about climate change is worrying about
the wrong problem.