Monsoon trough of the summertime Asian monsoon is in its normal orientation (oriented east-southeast to west-northwest), tropical cyclones along its periphery will move with a westward motion. If it reverses its orientation, orienting southwest to northeast, tropical cyclones will move more poleward. Tropical cyclone tracks with S-shapes tend to be associated with reverse-oriented monsoon troughs. The South Pacific convergence zone and South American convergence zones are generally reverse oriented. The failure of the monsoon trough, or the ITCZ, to move south of the equator in the eastern Pacific Ocean and Atlantic Ocean during the southern hemisphere summer, is considered one of the
Bounty Trough the South Island's coast. It covers an area of approximately . Much of The Bounty Trough lies at depths of , and it marks an indentation in the "coastline" of the largely submerged continent of Zealandia. A curious feature of the Bounty Trough is that it marks the continuation of several main river features in the South Island – the "Otago Fan Complex". This is a distinct series of channels existing in the base of the trough which is an extension of the Clutha and Waitaki River systems. Both these rivers, especially the Clutha, are noted for their fast flow.