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
Sagami Trough Sagami Trough The also Sagami Trench, Sagami Megathrust, or Sagami Subduction Zone is a long trough, which is the surface expression of the convergent plate boundary where the Philippine Sea Plate is being subducted under the Okhotsk Plate. It stretches from the Boso Triple Junction in the east, where it meets the Japan Trench, to Sagami Bay in the west, where it meets the Nankai Trough. It runs north of the Izu Islands chain and the Izu-Bonin-Mariana Arc (IBM). Megathrust earthquakes associated with the Sagami Trough, known as Kantō earthquakes, are a major threat to Tokyo and the Kantō Region