Why do countries and cities near the equator rarely experience hurricanes? The following article will provide you with the answer.
Many countries around the world, particularly Vietnam, are very familiar with the occurrence of storms, including super typhoons with immense destructive power, such as Typhoon Yagi, which recently struck the northern provinces of Vietnam.
In contrast, countries and cities located near the equator, such as Singapore, Indonesia, the Maldives, and Colombia, are largely unaffected by hurricanes.
So what is the reason for this? The simple answer is that hurricanes are almost never formed in the equatorial region of the Earth.
Historical maps showing the formation and movement of storms and super typhoons indicate that they rarely form and move in areas near the equator.
Map showing the formation and movement of storms from 1945 to 2006 (Image: IFL).
Storms tend to form in tropical sea areas with water temperatures exceeding 26 degrees Celsius. When water is heated, it evaporates and rises, cooling down to form clouds and thunderstorms.
Hurricanes do not form in the equatorial region primarily due to the lack of an important factor known as the Coriolis effect, a physical phenomenon related to the rotation of the Earth, which plays a crucial role in creating and maintaining the swirling motion of tropical storms.
The Coriolis effect is the force caused by the rotation of the Earth, which causes air to move in a curved path rather than straight. This effect is the main factor that helps tropical storms rotate and form a cyclone. Tropical storms resemble a spinning wind turbine, originating from the Earth’s rotation.
However, at the equator, the Coriolis effect is very weak, almost zero, making it insufficiently strong to create or maintain the swirling motion necessary for storm formation. The further away from the equator, the stronger the Coriolis force becomes, in conjunction with factors such as sea surface temperature in tropical regions, creating favorable conditions for storms to form and develop.
Additionally, other factors contribute to the difficulty or rarity of storm formation near the equator, including the stability of sea surface temperatures in this region, which leads to atmospheric stability.
In equatorial areas, air tends to move vertically upward due to the lack of horizontal convection (the movement of air from high-pressure to low-pressure areas), which hinders the formation of air vortices, the very phenomenon that creates storms.
Of course, there are exceptions, and some storms have formed in areas close to the equator. For instance, in December 2001, Typhoon Vamei formed just about 1.5 degrees north of the equator, near the island of Borneo (part of Indonesia).
This was one of the rarest storms ever recorded to form close to the equator.
Satellite map showing the path of Vamei, one of the rare storms formed in the equatorial region (Image: Nilfanion).
This storm moved west-northwest, making landfall in southern Malaysia and Singapore on December 27, 2001. Although its intensity was not strong, the storm still caused heavy rainfall and flooding in Singapore, Malaysia, and Indonesia, resulting in five fatalities.
To this day, Typhoon Vamei remains one of the notable meteorological events because it is one of the rare storms formed in the equatorial region, despite its relatively low destructive power.