Hadley cell
Subtropical Indian Ocean Dipole related anomalies over the Southeastern Indian Ocean is also suggested to impact the position of Mascarene high and thus the Indian summer monsoon. Positive (negative) Subtropical Indian Ocean dipole events during boreal winter are always followed by weak (strong) Indian Summer Monsoons. During positive (negative) SIOD event, the Mascarene High shifting southeastward (northwestward) from austral to boreal summer causes a weakening (strengthening) of the monsoon circulation system by modulating the local Hadley cell during the Indian Summer Monsoon event.