Did I mention the bright sun? I certainly was reminded of it the next morning, when I awoke to a face that looked rather like a boiled lobster, and felt worse. First came the blisters, then the stiff, leather-like carapace of deadened skin, then the reptilian hide-shedding. I still fear that somewhere in that trip the seeds of skin cancer were planted in my cheeks.
A few years back I was on another peak: Denali. For two weeks, Tim and I lugged our packs and sleds up that enormous mountain, often under a blazing Alaskan sun. But except for the tip of my tongue (burned on the last day, while hiking to the glacier airstrip with the sun dead ahead) the skin on my face was virtually the same shade as when we left Seattle. The difference? Good sunscreen, and lots of it.
These days, the jury is out on whether sunscreen can really reduce the chance of contracting skin cancer. But why take the chance? Between good sunscreen and changes in behavior, you can reduce the odds of coming up with a sunburn that will at best ruin your trip, at worst cause some real problems further down the road.
Unquestionably, today's sunscreens are an astonishing improvement over the clown-white zinc oxide concoctions that were the only things available a few decades ago. All sunscreens today are made without PABA (para-aminobenzoic acid), an ingredient in early sunscreens that was effective at blocking the sun but caused a skin reaction in some people. And while any sunscreen is better than none, a few guidelines will ensure that your sunscreen does what you want it to. Some rules:
Do the math: Sunscreen is rated on a numerical scale, usually 10 to 40. This quantifies its "SPF" (sun protection factor). An SPF of 15, for instance, means that in 150 minutes of sun time you'll get about the same exposure as you would in 10 minutes without sunscreen. An SPF of 15 is about right for most people in most situations. However, people with sun-sensitive skin or who are at high elevation or on snow - where thinner air and reflectivity increase the UV rays hitting your skin - then a higher number is best. But you're wasting money with sunscreens that have a higher SPF than 30, as the additional benefit is minimal. And keep in mind, SPF factors don't add up. You can't put on two layers of SPF 15 sunscreen to get an SPF of 30.
Use it early. It's best to apply sunscreen at least 15 minutes before you're exposed to the sun. For hikers, for instance, that means putting it on before you leave camp for the day to avoid the hassle of a mid-morning stop to apply sunscreen. Use plenty, thoroughly coating all exposed skin and hitting trouble spots such as the ears, neck and inside the nose (hikers on snow slopes often end up with sunburned nostrils as the sun's rays bounce off the snow and are re-directed upward).
Use it often. Some sunscreens are billed as offering all-day protection. And while so-called sports-type sunscreens do a good job of resisting runoff caused by sweat or swimming, it's still a good idea to re-coat at least once a day - probably early in the afternoon, as the sun hits its peak burning capability.
Use it everywhere. Clothes can help reduce sunburn, but they aren't sun-proof. It may be wise to apply sunscreen even under your shirt - assuming you're hiking while wearing a T-shirt, or something else that is light in weight.
Don't forget the part. More than once I've seen friends return from a trip in the hills with a bright red stripe right down their heads. They went hatless, and the sun hit the part of their hair.
Take a few precautions, and you'll come back from your wilderness with great memories and maybe a light tan - not a sunburn. And that's a worthy goal.