Yes. black ice is road ice that doesnt even seem to be there until you are in the process of slipping and sliding all over the road, into old ladies on the crosswalk, and into ill placed trees.
That's really scary...we once were on the highway when black ice formed on the road...we slowed (like everybody) back to 20 miles per hour, but still, the car was sliding away to the right all the time.
I hate killing the environment like this, but black ice is very dangerous and the only way you can stop it is by putting a lot of sodium chloride on the roads. Bad for the environment, but it keeps the roads dryish.
Simple salt isnt used up north. It refreezes all too fast. They use stuff called HEET. Its a quai salt compound with a few special additives that makes it positively hot when in contact with ice and water. Melts it all fast and keeps it that way many, many times longer.