Protecting Gel Coat on 5er

[BigMike]

I keep my 5er in an open ended polebuilding behind my house. However, the Gel Coat cap is exposed to the sun for about half the day. I noticed yesterday, some areas are starting to turn yellow. Is there anything I can do, short of covering the cap, to prevent this and also get the yellow out? What will happen if it continues to be exposed? Will the fiberglass eventually break down and start cracking?

 

[BGlidewell]

http://www.303products.com/techinfo/uv1.htm