The vortex splitting process from interaction between a mesoscale vortex and two islands

Mesoscale vortices are major carriers of oceanic material and energy transfer, transporting large amounts of high-energy, temperature-anomalous water bodies during their movement. This significantly impacts both the ocean and the atmosphere. Based on the distribution of the North Brazil Curren rings and the Lesser Antilles in the eastern Caribbean Sea, we use the Regional Ocean Model System ocean circulation model to construct an idealized vortex. Simulations are conducted by varying the distances between the two islands and the scales of the islands to analyze how different parameters affect the vortex path and structural evolution. Using theoretical derivation and numerical simulation results, we construct a dimensionless parameter involving vortex diameter, island diameter, and the distance between the islands to determine the conditions under which vortex splitting occurs. The reliability of this dimensionless parameter is verified using experimental data and satellite data from St. Vincent and Barbados from April 6 to May 6, 2000.