Spherical lenses mirror the shape of your eye; they are curved on both the vertical and horizontal axes, tapering outward from the middle of the lens to reduce distortion. This also maximizes the rider's peripheral vision.
A cylindrical lens is a lens which focuses light which passes through onto a line instead of onto a point, as a spherical lenswould. The curved face or faces of a cylindrical lens are sections of a cylinder, and focus the image passing through it onto a line parallel to the intersection of the surface of the lens and a plane tangent to it. The lens compresses the image in the direction perpendicular to this line, and leaves it unaltered in the direction parallel to it (in the tangent plane).
The glare of the sun on the snow and other water surfaces is highly polarized. Indeed, the glare can be almost completely horizontally polarized, depending on the height of the sun. In addition, all reflections from objects above water are partially polarized. These include clouds and even the sky (the reflected sky gives most of its blue colour to the sea).These are examples of polarization by reflection. Although the light from the sun is not polarized, it can be separated into two polarized components that are reflected and transmitted in different amounts by the surface of the water. More of the horizontal component will be reflected than the vertical component, thus partially polarizing the reflected light. With polarized goggles they will stop the glare and make the snow appear more transparent enabling you to see tracks and shadows within the snow pattern enhancing your vision while in technical terrain.