Auto body repair & detailing: paint, uv rays, screeners

Question
My suv has a cracked look to its paint on the roof and hood.  What caused it.

Answer
We call it "Checking and Cracking", generally it is caused by the uv rays from the sun thinning out the clear coat. The finish needs to be well protected with wax..If the paint is colorsanded to thin to the point that the clear is so thin there is no screeners left in he clear it will bake the finish in a sense..  All you can do is strip it and paint it over..