The C‐Shaped Landmass: A Key Driver of Monsoon Formation

Abstract Monsoon dynamics research has largely focused on idealized rectangular continents, primarily in the Northern Hemisphere mid‐latitudes. To investigate the broader impact of landmass configuration on monsoon formation and variability, we conducted extensive sensitivity experiments. Our findings reveal that a C‐shaped continent in the tropical and subtropical latitudes is optimal for monsoon development. This configuration fosters three key monsoon characteristics: (a) A well‐defined pathway for water vapor transport, involving cross‐equatorial winds and monsoonal trough turning winds; (b) A thermally induced low‐pressure system over the southeastern continental margin, driving persistent water vapor convergence; and (c) A distinct monsoon rain belt extending from the southeastern corner of the continent into adjacent oceans. These results provide a definitive answer to the question of which landmass shape is most conducive to monsoon formation and significantly advance our understanding of monsoon dynamics.