What is a Rossby wave?


Rossby waves, also known as planetary waves, occur naturally in fluids in rotation. Within the ocean and the atmosphere of the Earth, these waves are formed as a result of the rotation of the planet.

The oceanic and atmospheric Rossby waves, also known as planetary waves, occur naturally largely due to the rotation of the Earth. These waves affect the climate and climate of the planet.
What is a Rossby wave?
Oceanic Rossby Waves

The waves in the ocean come in different shapes and sizes. The slow-moving Rossby ocean waves are fundamentally different from the waves on the surface of the ocean. Unlike the waves that break along the coast, the Rossby waves are huge undulating movements of the ocean that extend horizontally across the planet for hundreds of kilometers in a westerly direction. They are so large and massive that they can change the climatic conditions of the Earth. Along with rising sea levels, King Tides and the effects of El Niño, the Rossby ocean waves contribute to high tides and coastal flooding in some regions of the world.

The movement of the Rossby waves is complex. The horizontal wave velocity of a Rossby (the amount of time it takes the wave to travel through an ocean basin) depends on the latitude of the wave. In the Pacific, for example, waves at lower latitudes (closer to the equator) can take months or a year to cross the ocean. Waves that form farther from the equator (in mid-latitudes) of the Pacific can take more than 10 to 20 years to make the trip. The vertical movement of the Rossby waves is small along the surface of the ocean and large along the deepest thermocline: the transition area between the warm top layer of the ocean and the colder depths. This variation in vertical movement of the water surface can be quite dramatic: the typical vertical movement of the water surface is usually four inches or less, while the vertical movement of the thermocline for the same wave is approximately 1,000 times larger . In other words, for a surface displacement of four inches or less along the surface of the ocean, there may be more than 300 feet of corresponding vertical movement in the thermocline well below the surface! Due to the small vertical movement along the surface of the ocean, the Rossby ocean waves are undetectable by the human eye. Scientists often rely on satellite radar altimetry to detect massive waves.

Atmospheric Rossby Waves

According to the National Meteorological Service, Rossby atmospheric waves are formed mainly as a result of the geography of the Earth. Rossby waves help transfer heat from the tropics to the poles and cold air to the tropics in an attempt to return the atmosphere to equilibrium. They also help locate the jet stream and mark the track of low surface pressure systems. The slow motion of these waves often results in quite long and persistent weather patterns.

Leave A Reply