Just because it’s cold doesn’t mean you can’t sunburn. Snow, in fact, is an excellent reflector/doublebroiler. Ergo, slather on the sunblock, which reflects the sun (as opposed to sunscreen, which absorbs UV radiation though might not ward off harmful UVA rays, and can contain ingredients e.g., benzophenone and homosalate with spotty health records). The good news: CLIMB ON! SPF 30 MINERAL SUNBLOCK ($18, climbonproducts.com) has only one active ingredient zinc oxide. Nontoxic and biodegradable, the lotion also nourishes your skin with ingredients like grapeseed oil, fair-trade shea butter, and aloe vera. It goes on with reassuring thickness and offers solid, water-resistant protection for any-season solar intensity.