Cyclones And Anticyclones: What Is The Difference?
Cyclones And Anticyclones: What Is The Difference?
Most readers are familiar with the term “cyclone,” but not with the term “anticyclone.” We take a closer look at cyclones and anticyclones and their differences.
A cyclone is defined as an air mass circulating a low-pressure system, rotating counterclockwise in the Northern Hemisphere and clockwise in the Southern Hemisphere. An anticyclone, though, circulates a high-pressure system, rotating clockwise in the Northern Hemisphere and counterclockwise in the Southern Hemisphere.
This description is rather short and cryptic, but it helps establish the fundamental differences between these two weather phenomena. We will examine both in more detail shortly.
To better understand these two weather phenomena and how they differ, one needs to define what they are and look at their characteristics.
Additionally, this post provides a detailed table that breaks down the primary differences between the two weather events.
Cyclones Vs Anticyclones
The difference between a cyclone and an anticyclone was already summarized in the introduction, but a more elaborate explanation will help to better understand how they differ.
The Difference Between A Cyclone
A cyclone is a pattern of winds that circulates around a low-pressure system. It rotates counterclockwise in the Northern Hemisphere and clockwise in the Southern Hemisphere. It is typically associated with wet and stormy weather.
An anticyclone is a pattern of winds that circulates around a high-pressure system. It rotates clockwise in the Northern Hemisphere and counterclockwise in the Southern Hemisphere. It is typically associated with dry and fair weather.
The difference in the direction the winds rotate in the Northern and Southern Hemispheres is a direct result of the Coriolis Effect, which causes the wind to deflect to the right in the Northern Hemisphere and to the left in the Southern Hemisphere.
(Read more about the Coriolis Effect in this article.)
Why these differences between a cyclone and an anticyclone occur will become more evident as we take a closer look at the formation and characteristics of each.
Definition And Development Of A Cyclone
As already described, a cyclone is a wind pattern circulating around a low-pressure system, counterclockwise in the Northern Hemisphere and clockwise in the Southern Hemisphere.
Most cyclones (and all their variations) form over the warm waters of the tropics. As the warm, humid air starts to rise, it creates an area of low pressure close to the surface.
Since winds blow from a high-pressure to a low-pressure system, they rotate and converge from the sides into this area of low pressure. This creates the familiar cloud pattern that we see with hurricanes, typhoons, and other tropical cyclones.
As the moist and humid air continues to rise, it cools down, and the water vapor can no longer stay in its gaseous form. As a result, condensation takes place, leading to cloud formation, which is usually accompanied by heavy precipitation.
Definition And Development Of An Anticyclone
As already described, an anticyclone is a wind pattern circulating around a high-pressure system, clockwise in the Northern Hemisphere and counterclockwise in the Southern Hemisphere.
Sometimes, the surface over which a body of air resides starts to cool down. It may be a result of land cooling down quickly due to a lack of solar radiation or as a result of a mass of air moving in over cold ocean waters.
In turn, this cools the air. As it cools, the particles contract and move closer together due to a loss of energy. This makes the air denser, increasing the pressure at the surface and resulting in the formation of a high-pressure system.
As mentioned, wind blows from a high-pressure system to a low-pressure system. In the case of an anticyclone, it blows and diverges away from the center of the high-pressure system. This results in the clear and fair weather one typically experiences in the presence of an anticyclone.
Cyclone vs Anticyclone: The Key Differences
One of the most important differences between a cyclone and an anticyclone lies in the vertical movement of air.
In a cyclone, air converges at the surface and rises upward. As the rising air cools, condensation occurs, leading to cloud formation and often precipitation. This upward motion is the primary reason cyclones are associated with unsettled and stormy weather.
In contrast, an anticyclone is characterized by sinking air. As the air descends, it warms and inhibits cloud formation, which typically results in clear and stable weather conditions.
On weather maps, this difference becomes easy to identify: low-pressure systems with inward-spiraling winds indicate a cyclone, while high-pressure systems with outward-diverging winds indicate an anticyclone.
The following table highlights the key differences between a cyclone and an anticyclone:
Also known as Lows
Circulates a low-pressure system
Winds converge toward the center
Winds circulate counterclockwise in the Northern Hemisphere
Winds circulate clockwise in the Southern Hemisphere
Associated with wet and stormy weather conditions
Commonly occurs in the Tropics and Subtropics
Also known as Highs
Circulates a high-pressure system
Winds diverge away from the center
Winds circulate clockwise in the Northern Hemisphere
Winds circulate counterclockwise in the Southern Hemisphere
Associated with dry and fair weather conditions
Occurs globally, often over continental interiors and subtropical oceans
Conclusion
As this article illustrates, there are some clear differences between a cyclone and an anticyclone. Both weather phenomena are characterized by wind circulation around a pressure system, but that is where the similarities end.
In this article, we examined the primary differences between these two meteorological events. We also took a closer look at how each phenomenon develops and what its characteristics are.
Until next time, keep your eye on the weather!