None because all of these countries are from earth
UV radiation generates ground-level ozone (O3) and some particulate matter (PM, frequently called aerosol) that include nitrate, sulfate, and organic aerosols causing adverse effect on human health and the environment. UV promotes the formation of hydroxyl radicals that act as cleaning agents for troposphere
Radiation has been around us throughout our evolution. So our bodies are designed to deal with the low levels we're exposed to every day. But too much radiation can damage tissues by changing cell structure and damaging DNA. This can cause serious health problems, including cancer
You won't notice much at sea. Maybe a slight change in sea level.
Closer to the land though, water will draw away from the land maybe leaving the sea floor exposed. Then it will surge back in, flooding the land and inundating the coastal area.
