What exactly is black ice and how do I drive on it?
Here's the best way. Winter is properly cold now, with Arctic blasts giving most of the country good reason to put on an extra layer and crank the heaters. It also means that something called black ice is much more common on the roads. In this case, black ice is neither AC/DCs 2008 album, nor is it a flavour of Smirnoff RTD. Here, it refers to what happens when water freezes over tarmac in such a state that it appears totally invisible. Normal ice freezes with a white tinge, which comes from air bubbles and minerals in the water. Black ice has very little of these, so it freezes transparent. The black part of the name comes from the tarmac, beneath the ice. Alden Williams/Stuff Black ice isn't literally black, its transparent. The name comes from the road surface visible beneath the ice. Its typically around at night, which adds to the invisible danger of the ice. Black ice can be formed by snow melting during the day, making the roads the wet, then refreezing at night as clear ice, rainfall wetting the road and forming puddles before the temperature drops and freezes solid, or when moisture in the air condenses and forms fog or dew that then freezes on the road. Because it starts as a watery surface, black ice is very hard to spot because it's extremely thin - it might look like a harmless puddle. Don't be lax just because your car's thermometer says it's above freezing, especially in the morning: the road surface might not have had time to heat up and melt the black ice. Hamish McNeilly/Stuff It looks like a puddle during the day so imagine how hard it is to spot at night. For that reason, be especially aware of wet-looking patches of road on an otherwise-fine day, especially if they are in an area that doesn't look like it gets much sun (a shady corner by a rock wall, for example). Bridges are more susceptible to any kind of ice, because cold air can circulate above and below and there's not as much insulation underneath to stabilise the temperature. Black ice can hang around much longer on rural roads, because the warmth and friction of traffic wears it away. SUPPLIED If youve ever driven on snow or ice before, the principles are the same for tackling black ice. If youve ever driven on ice or snow, the principles are largely the same. A car can really only do three things: accelerate, steer and brake. If you're driving on ice and/or snow with very little traction, the key to staying safe is to only do one of those things at a time. The problem with black ice is that by the time you've hit it, theory might mean little and panic can take over. The difference between normal ice and black ice is that the former is more likely to be sustained - you'll be aware you're driving on it, it'll go on for a long distance, and you can modify your driving style to suit. With black ice, there will be a clear beginning (even though you might not have spotted it) and a clear end - more than likely after a few metres. So if you hit black ice and lose control, don't panic and try to fight your way back. You won't be able to because your car will have virtually no grip or traction (much less than on snow, for example). While your natural instincts may be to turn into the skid, you need to resist that to a degree because you shouldnt make any sudden movements on the wheel, and its more important to know exactly where your wheels are pointing when the grip comes back. Instead, stay calm and only make minor adjustments on the wheel, steering slightly into the skid if necessary, but certainly no crossed arm, full-lock style movements. Ultimately, staying calm will help you more than anything. Remember, black ice doesnt last long and the grip generally returns quickly. As long as youre driving at an appropriate speed and stay calm, youll be fine.