some questions:

UVA rays: have they increased of late, due to ozone depletion?

Shea butter: a natural SPF of 15. Does olive oil also provide a natural SPF?

Nutritional angle: I've read that eating carrots helps children to develop healthy melanin. Other foods that may help with sun exposure?

Alternating sun with shade: skin-applied sunblocks are necessary should shade become difficult to obtain, but how about simply self-regulating with access to shade?

Re: comments
I have heard that Shea Butter can boost sun protection. I am happy to know it has SPF as high as 15. I am seriously considering using that as a daily cream on my face. I did not know about carrots increasing melanin...that sounds like it could be helpful. I don't know about olive oil being protective of UVA or UVB rays but I know that it contains Vit E which is an antioxidant which may help heal the skin. From what mainstream nutrition has taught me, however, it is more likely to work better as an antioxidant if you consume it.
What I did not mention in the blog is other ways to protect ourselves from the sun. I think that limiting our exposure and going in the shade or indoors often helps. Going in the shade will protect more than being in direct sun, but even in the shade the UV rays bounce of sand, dirt, snow etc and can reach us. Wearing protective clothing, hats, and glasses is helpful....but it can make us hot.
From what I have read, all UV rays are more intense now that we have less ozone. The hole in the ozone is mostly over the southern hemisphere of the planet and spans a large part of Austrailia. Sadly, they are more screwed than we are right now.

Re: Shea Butter question
Does anyone have a good reference about Shea Butter and its sun protective qualities? I am curious to find out if it protects against UVA and UVB.