An Overview of Solitons in the South China Sea
Most of the world's oceans are characterised by two layers: The water in the near surface layer has a lower density while the deeper layer has a higher density. Because the top layer is 'lighter', it rides above the denser layer below, much like oil over water. In certain circumstances, waves can develop in the interface between these two layers. Such waves are variously known as solitons, internal solitons, internal waves or non-linear internal waves (NLIW).
Squalls in the South China Sea
Squalls refer to a sudden increase in wind speeds. The World Meteorological Organisation's definition of a squall is: "A sudden increase of wind speeds by at least 16 knots, the speed rising to 22 knots or more and lasting for at least one minute.". Squalls are associated with thunderstorms and heavy showers and they can last for several minutes but they normally last for less than 10 minutes.