Types of Tropical Cyclones



Types of Tropical Cyclones

Most authorities define tropical cyclones as rotating systems of thunderstorms and clouds, which emanate from sub-tropical or tropical areas. The large majority of such areas are within the vicinity of the equator. Tropical cyclones mostly occur in such areas along the Atlantic Ocean, the eastern Pacific Ocean, the Gulf of Mexico and the Caribbean. Some forms of tropical cyclones are deadly and can cause massive damage to people as well as property (Larson et al., 2005). Their formation occurs through the warm air, which rises above the sea and forms clouds that release massive amounts of energy. Severe storms represent the most significant effect of this process. The storms in this context can evolve into cyclones especially when they combine with the moving areas of low pressure and winds (Larson et al., 2005). Depending on the degree of their strength, tropical cyclones can adopt varying forms typically referred to as hurricanes, tropical storms, and tropical depressions.


Hurricanes are also famous as typhoons. These types of tropical cyclones refer to systems with sustained speeds that exceed thirty-three miles per second or one hundred and eighteen kilometers per hour. In this form, the tropical cyclone tends developing an eye, which refers to the specific area of relative stillness and low atmospheric pressure at the center of the circulation. In most cases, the eye is visible as a minute circular cloud-free spot in satellite images. The eyewall, which represents an area that surrounds the eye measures between sixteen and eighty kilometers in width (Ulbrich et al., 2009). In their mature form, hurricanes tend to highlight inward curves that resemble football stadiums at the top of the eyewall. This effect is widely famous as the stadium effect.

Tropical Storms

As forms of tropical cyclones, tropical storms represent strong thunderstorms characterized by maximum sustained winds and defined circulation on the surface. The winds tend to travel at a speed of around thirty-four knots, which ranges from sixty-three to one hundred and nineteen kilometers per hour. At this point, they tend to develop a distinct cyclonic shape. Unlike hurricanes, tropical storms lack an eye. Further comparison reveals that they are less intense. However, this trait does not necessarily imply a diminished capability for destruction (Rozoff et al., 2006). They incorporate strong, forceful winds, which can dismantle shingles and a wide array of airborne objects. This aspect renders them extremely dangerous to houses and power lines. The danger of tropical storms tends to increase with heavy rainfall, which causes inland flooding.

Tropical Depressions

Tropical depressions form when groups of thunderstorms come together under the relevant atmospheric conditions for an adequate time. The winds at the center of this phenomenon tend to fluctuate between twenty and thirty-four knots or twenty-three and thirty-nine miles per hour. The classification of a tropical depression occurs with the initial appearance of the combination of organized circulation in the heart of the thunderstorm and low pressure. The view of the tropical depressions from satellite images reveals little or lack of organization. However, the analysis of a series of satellite images usually reveals a slight amount of rotation (Georgiou et al., 2003). As opposed to hurricanes, which are notable for having round shapes, tropical depressions bear the semblance of individual thunderstorms in a single grouping. These types of tropical cyclones represent the least deadly or devastating in comparison with the three types classified by most authorities.



Georgiou, P. N., Davenport, A. G., & Vickery, B. J. (2003). Design wind speeds in regions dominated by tropical cyclones. Journal of Wind Engineering and Industrial Aerodynamics, 13(1-3), 139-152.

Larson, J., Zhou, Y., & Higgins, R. W. (2005). Characteristics of landfalling tropical cyclones in the United States and Mexico: Climatology and interannual variability. Journal of Climate, 18(8), 1247-1262.

Rozoff, C. M., Schubert, W. H., McNoldy, B. D., & Kossin, J. P. (2006). Rapid filamentation zones in intense tropical cyclones. Journal of the atmospheric sciences, 63(1), 325-340.

Ulbrich, U., Leckebusch, G. C., & Pinto, J. G. (2009). Extra-tropical cyclones in the present and future climate: a review. Theoretical and Applied Climatology, 96(1-2), 117-131.