Good question. In my opinion, the theory of tropical cyclogenesis is originally proposed based on observations and simulations of typical tropical cyclones. Thus, it might not be able to well explain the "tropical-like cyclones" over the Black Sea or the Mediterranean Sea (also called Medicane). Some researchers believe that such tropical-like cyclones could be under a transition state between tropical cyclones and subtropical cyclones. Theories such as the Wind Induced Surface Heat Exchange (WISHE) mechanism are formed to explain the development of tropical-like cyclones. However, there are different opinions toward these theories, and more research is needed to further improve the current theories.

Dear Wu Zuhang.

Unfortunately, there is no correct aerodynamic model of vortex tubes (tornado and typhoon). These are vortices with downward air movements in the center. I don't even know the correct physical model of a cyclone with an "eye" of the storm. All scientific disputes use the thesis that cyclones do not form at the equator, and tropical cyclones form in the latitude band up to 30 degrees due to a decrease in the horizontal component of the Coreolis force at low latitudes. My example destroys this main thesis. At the latitude of the Black Sea, the horizontal Coreolis force is already sufficient for the transformation of the convective structure into an ordinary cyclone. There are other questions as well. In fact, at the equator, where the horizontal component of the Coreorlis force is zero, but cyclones form. These are not local vortex tubes with an "eye" of the storm, but ordinary cyclones. I've attached an image of the Boff equatorial cyclone (sourced from the Jaxa website). What's not clear? Why do these cyclones exist and why, having moved to the tropical latitudinal zone, do they become cyclones with the "eye" of the storm?

Dear Borys Kapochkin,

Thank you for providing these examples. The existence of tropical cyclones at the latitude of the Black Sea (where SST is relatively low) and near the equator (where Coreolis force is relatively weak), may indicate that both SST and Coreolis force are not the primary factors that control cyclogenesis in these areas. Thus, it is critical to understand the key environmental parameters that control cyclogenesis. I suppose the cyclonic vorticity affected by atmospheric conditions could play a more important role in cyclogenesis in these areas. But the key genesis factors might change in different areas.

The place of generation of the cyclone with the eye of the storm coincides with the place of methane release from the lithosphere. Look up a map of seabed methane sources from the internet. In this place in September 1928, a large-scale fire of methane over the sea was recorded twice. When methane is oxidized, water vapor is formed. When it condenses, energy is released. If there is little water vapor, a cyclone is formed. If there is a lot of water vapor, a cyclone with an eye of a storm is formed. This fact shows that the coreolis force is not involved in the formation of a cyclone with a storm eye.

I attached a photo of methane release from the lithosphere. Photo from an open Internet source. I personally recorded with a sonar, filmed an underwater video and measured the volume of methane release in different parts of the world's oceans. I have repeatedly recorded such processes even on the beaches of Odessa (Black Sea, Ukraine).