If you know some keywords, I can search them for you. As far as I know they only come to the surface to recalibrate the navigation systems. I've heard they sometimes don't harbour for more than a year, this of course depends on the size of the submarine. No, the bacteria remained directly exposed to the radiation. No it doesn't, it just meen their are insulating gases in the air.
Greenhouse gasses are more opaque planetary radiation than for solar radiation.
Solar radiation is what directly comes from the Sun and planetary radiation is what is reflected from the planet's surface. As for the debacle about Earth's greenhouse effect, there are only doubts about the quantity of the temperature increase caused by the greenhouse gasses. Also it is argued if the greenhouse gasses are the only reason for temperature increase. If that were true Earth would have been unable to ever evolve life. To that I agree, but as long the greenhouse effect is not too large the temperatures will not become so high that no live can exist.