Huge disk of ice in the river has a diameter of more than 15m in Russia.
By 2016, scientists at Liege University (Belgium) discovered that it was the temperature change that spurred the spinning disc. When the temperature rises, the water becomes less dense. When the water is cooled in a place adjacent to the ice surface, a swirl is formed.
The team simulated how temperature changes the water density in the laboratory.
They create ice floating on the water by freezing tap water in a shallow dish and then pouring it into cool water. For better control of the experiment, the researchers conducted a second test with a more effectively fixed tape cassette by attaching a bead to the center of the cassette and sticking the magnet to the bottom of the tank.
When the warm water tank creates a vertical whirlpool, the tape disc begins to move faster. This shows that river water flow is essential to stimulate whirlpool rotation. Therefore, the surrounding landed lakes or melting icebergs will not appear ice disk effects.