The sun’s impact upon ourselves is huge. Just not in terms of the basic life-giving importance of it, but also in terms of comfort and the joy it imparts to our moods.
Back in January of 2006 I was in the Philippines. We went to the city of Baguio and Baguio is high up and so it is cool. In fact, they can grow many of the berry fruits such as raspberries, blackberries, blueberries, etc up there and they have pine trees as well. In the morning the sun would be out and while it was notably cool (however it was far from cold) the sun would just obliterate that coolness. The word that comes to the top of my mind when thinking of it is glorious.
However, in the afternoon clouds would move in from the nearby ocean waters and screen the sun from us. Glorious changed to miserable, even though the temperature did not appreciably drop.
Isn’t that how it works with skiing too? If it is 15° F with sunshine doesn’t it feel glorious? However, 15° F without sunshine while maybe not miserable is just cold? Even sitting in the house I notice this too, two days one with sunshine and one without. It can be the same temperature where I am at and the sunny day just seems warmer.
We do pay a price on the sunshine though. Shadows are much darker and if you are skiing on a shaded run, then the terrain flattens out big time. Even on a cloudy day the terrain will flatten out but the effect is much more pronounced in sunshine shade. Perhaps it is more psychological than reality.
You ski one run in full blast sunshine and every little variation from the perfectly smooth leaps out at you and then you go into a shaded run where it is all flat. On a sunless day the terrain all over is just flat so you come to accept it all as normal for the day, whereas on the sunny day it is not normal.
However, if you are on your edges, poised in a good athletic stance on your skis, and are in control you can deal with “surprises” just fine.