It can be achieved in ToT pretty easily using the change terrain action combined with the random turn trigger. I guess you may need to reserve a terrain slot or two for the purpose.
In Fortress Europe I was considering including an event to represent the capture of the Schwammenauel Dam in the Hürtgen Forest. The idea was that after the capture of Liege you had a limited number of turns to take Aachen (which would have to represent the Hürtgen Forest and Dam too). If you did not take Aachen in time a change terrain event would convert the terrain around the Roer and Maas rivers into swamps (impassible) severely hampering the allies advance and destroying any units in the way. I had to scrap the event due to lack of space but I think it would have worked!
Sorry keu, I misunderstood your first post!
I guess if you combined the change terrain event with a destroy improvement event (destroying Supermarket) that could replicate a famine.
Plague could be replicated with a nuclear bomb that would wipe out the units in a city (though I'm not sure if it reduces the population)
In a multiplayer game there could be a civ called Nature with spy units renamed Plague Rats which could poison the water supply. Obviously this would be no good in single player mode.
Immediate famine might be hard. Beyond eliminating granaries by obsoleting the pyramids you will need to clear out the foodbox...
Use events to create about a hundred settler flag units that will destroyed one turn after they drain the foodbox?
The most of settlers will be auto-disbanded because a lack of shield support. And some number will remain.
Did the remaining settlers drain the foodbox?
If your concerned with removing the settlers just bottle the settlers up in one tile on the edge of the map and use a terrain change event to remove them after one turn.
Try making them owned by Barbarians but supported by the city to eliminate what the player can see.
You could also try using food routes to support a city above and beyond its domestic food production and then cut the food route. This is not an immediate effect due to the food box but it could cut food production to help keep a city in famine.