At 6000 ft the UV here is pretty intense. So much so that it seems to feel hotter here out in the sun on a bright sunny day, than it does 2000 ft lower down in the valley, even though the thermometer reads almost 10°f cooler up here than it does in the valley. I do of course wear long sleeve shirts and full brimmed hats if I'm going to be out in the sun much, wherever I am around here. This is the high desert afterall!
But I rarely get sunburn of any kind, as I'm quite accustomed to high altitude what with working 15 years at 12,500 ft and all my backpacking and climbing to even greater heights. Also all my high lake canoeing which is a real solar challenge also, what with water reflection added into the mix.
Still, with all the precautions I've generally taken, skin cancers will be no surprise if/when they start showing up. It's just the kind of life I've chosen to live!