Hypothermia
This is the lowering of the body's core temperature. It can happen in water or on land. Hypothermia does not require extreme cold and accelerates with wind and wetness. Dressing warmly in water resistant layers helps, but if immersed, quickly replace wet clothes, keep moving to generate body heat, and find immediate shelter and warmth.
Snow Blindness
This occurs when direct and reflecting sun glare are too bright for the eyes. Riding without good quality, UV protected sunglasses can cause permanent damage.
Frostbite
Frostbite results from freezing temperatures and poor circulation. Most common on extremities and exposed skin, it can be identified by unnaturally white and numb skin surrounded by harsh red colouring. Cover up and layer well, making sure that socks fit loosely within your boots. And remember mitts with liners are warmer than gloves.
Wind Chill
Wind chill is lower temperature caused by wind and/or the forward momentum of a fast moving sled. Wind chill exposes you to severe cold which in turn can cause hypothermia. Wind-proof outer garments, extra layers and a balaclava will offer some protection, but keep your face shield down to prevent wind burn and to protect your skin and eyes.