Russian scientists have succeeded in explaining how the meteorological phenomenon ‘pillars of light’, characterised by exceptional luminescent effects on water droplets in freezing fog, occurs. The results of the finding may be useful for biological research.
Scientists from Tomsk Polytechnic University (TPU), in collaboration with an international scientific team, discovered that the water particles that make up the fog, when frozen (from 10℃ to 15℃ below zero), have a structure similar to that of jelly beans: the liquid is inside an icy shell. Such structures acquire resonant properties and can contribute to the formation of magnetic fields. The strongest magnetic impulse is emitted at the moment of freezing of the drop, which is the cause of atmospheric optical phenomena, known as light pillars.
Specialists point out that ice fog can be considered a natural metamaterial with features of an optical neural network. The small particles of frozen water can communicate with each other by means of magnetic impulses, which are also used by some representatives of the animal world, such as birds. Based on that, their internal navigator functions during seasonal migration, the study explains.
The team of scientists from Tomsk Polytechnic University, the Faculty of Physics of Moscow State University and the Huaiyin Institute of Technology in China worked out a model of magnetic effects arising in a drop of water freezing in fog. In the course of this process, the experts discovered the emergence of the Fano resonance, a phenomenon that can theoretically help to create a number of new systems of practical importance.
The authors of the research indicate that the intensity of the Fano resonance varies depending on how thick the ice shell of a frozen particle is, and detail the occurrence of this effect as follows: if a wave is launched into a body of water and then the same wave is launched so that it forms an angle with the first wave, their collision will produce a new crest. At the same time, due to weather and relief irregularities, the crest will be uneven. The same happens during the interference of electromagnetic waves.
‘During the freezing process of a drop, the intensity of magnetic and electric fields increases at its poles, which causes unusual optical phenomena,’ said project leader Igor Minin, professor at the Department of Electronic Engineering of TPU's School of Non-Destructive Testing and Safety Engineering.
He also added that to confirm the performance of the obtained model, experimental activities are needed, which is not yet impossible due to the lack of appropriate equipment.
Mínin pointed out that existing theoretical models do not take into account magnetic effects, while they, the scientists, propose specifications that will one day make it possible not only to control the light in the fog, but also to explain the behaviour of various living organisms.
