Global Warming lofts more water vapor and pushes it into the ozone layer, where it helps deplete ozone.
Ozone depletion allows increased levels of UV to reach Earth's surface, where it can only be converted to heat, but ozone is a greenhouse gas so it allows heat out more easily. So the days get hotter but the night can get cooler. Just not a lot of energy arriving between UV-215 thru UV-280, so the positive feeback is not all that clear.
I personally think that they are related. One major problems why where experiencing this global warning is the inability of the earth to managed the excessive CO2 within our atmosphere. The Ozone depletion, also plays an important role as the Sun's harmful UV is not being blocked on that area. Imagine it hitting directly the ice caps, that'll explain why where having sudden climate change. That's my basic understanding about it.
You should look at this: http://en.wikipedia.org/wiki/Ozone_deple...
Search for: "There are five areas of linkage between ozone depletion and global warming:"
Notes: Ozone is a greenhouse gas and it warms the stratosphere - it absorbs ultra violet radiation.
As OzoneGuy says, days are warmer nights cooler because at night the heat more easily escapes into space.
