How many people know what wormwood is (not to be confused with wormwood)? This is actually a very interesting question. Indeed, despite the fact that every person has encountered this phenomenon in real life, only a few know about its true nature. And therefore, let's dwell on it in more detail.
What is wormwood?
Wormwood is a non- freezing window on the surface of a reservoir. It is a hole in the middle of an ice sheet that does not stretch even in the most severe frosts. It should be noted that a similar physical phenomenon can be observed both in flowing and in still waters.
We hope that after the foregoing it becomes more or less clear what wormwood is. However, one more important point should not be overlooked. Namely, that wormwood is called as gaps in the whole cover of ice, and holes on drifting ice floes.
Why do wormwoods form?
The greatest accumulation of ice gaps can be observed on rivers with a high flow rate. In such conditions, the water simply does not have time to freeze and turn into a hard crust. Wormwoods also form in places where the release of warmer waters. It can be, for example, industrial drains, underground keys, sources and so on.
The fact that such a wormwood is well known to sailors floating in the northern waters. They can often observe this phenomenon in those places where a strong wind splits drifting ice floes in half.
Why does the wormwood not freeze?
To begin with, in those places where warm water rises to the surface, wormwood simply cannot disappear. Indeed, due to temperature changes, the ice instantly melts, forming an empty window.
If we talk about deep rivers or reservoirs, then things are different. There at night a thin ice crust forms on the surface of the water. With the arrival of dawn, the wind rises, which instantly destroys the ice cover. Only those sections that are located near the shore, or fenced off by a certain barrier, are not influenced by wind.