By fog, Nicholas, I assume you mean the weather-related variety, not fog inside the lenses. And snow was it snowing? Or were your skis kicking up snow?
Anyway, heres what I have to say on the subject. It sounds as if you were simply having a hard time seeing and picking up topographic features due to flat, foggy light. In my experience, lenses with more reddish tint are useful in these conditions. They block out the flat, blue light that makes everything look one-dimensional when its foggy. Most ski-goggle lenses already are sort of yellow-orange, but look for some that are more of a rose color, as these offer the best contrast. Oakley A-Frame goggles ($85; oakley.com) come with a choice of several different lensesone is a dark persimmon" that would work well.
As for polarized lenses, I think the jury still is out. They dont increase contrast so much as they reduce glare, such as sun reflecting off an icy patch. But its not necessarily a bad thing to be able to SEE that icy patch, so not everyone thinks polarized lenses are good for skiing. Plus, theyre expensive. Smiths Phenom goggles are polarized and have nifty features such as vents that can be opened or closed, depending on air temp and weather conditions, Theyre $169 (smithoptics.com).
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