This question is not a duplicate of this question. They're similar, but this one has one very large difference: only a large area has permanent cloud cover, not the whole planet.
If low clouds or even fog completely cover a large area (let's say 100 miles sq, about 161 km sq), what would be the effects on the climate? Could people still live there? (Disregard for the moment whether they would want to.)
- Assume that light can get through, just as light does on a rainy day. The sky and sun cannot be visibly seen though.
- Beyond where there are clouds, the climate is normal and similar to that of Earth.
- I don't know if it matters or not, but the area directly below the clouds is a vast swamp.