On the role of distributed helicity in the formation of hurricanes.

Ephim Golbraikh1, Peter Frick2 and Rodion Stepanov2, (1)Ben-Gurion University, Department of Physics, Beer-Sheva, Israel, (2)Institute of Continuous Media Mechanics, Perm, Russia
Abstract:
The problem of formation (suppression) of hurricanes is one of the most important problems in the physics of the atmosphere and ocean.

Till now, no clear picture of the hurricanes formation. Many years ago, in the paper [1] has been proposed a model amplification spiral vortex (such as typhoons), based on the hydrodynamic alpha-effect (HAE). However, in contrast to magnetic alpha-effect, the role turbulent helicity in the behavior of the hydrodynamic systems of hitherto considered passive [2], and consequently, this theory has not has been developed. On the other hand, some experimental data and theoretical estimates indicate that the helicity can influence the process of the formation of large-scale vortices.

In the present work, based on the theory of the distributed helicity [3], we show that under certain conditions, helicity ceases to be a passive scalar and strongly influences the transfer of energy from the large scale to small, leading to its accumulation on the large scales, with subsequent transfer into a mean flow. At the same time, we suggest that the influence on a hurricane can be carried out only at the stage of its formation, and we discuss of the behavior some of the parameters that are the predictors of the hurricanes occurrence. References

[1] Moiseev, S. S., Sagdeev, R. Z., Tur, A. V., Khomenko, Shukurov, A. M, Physical mechanism of amplification of vortex disturbances in the atmosphere,

Soviet Physics Doc., Vol. 28, p.926, 11/1983.

[2] H. K. Moffat, Magnetic Field Generation in Electrically Conducting Fluids (Cambridge University Press, Cam- bridge, 1978).

[3] R. Stepanov, E. Golbraikh, P. Frick, A. Shestakov, Hindered energy cascade in highly helical isotropic turbulence, arXiv:1508.07236v2