What are the physical hazards of tropical cyclones and their impact on people and environments?

Tropical cyclones bring a range of physical hazards that can threaten people and the environment. This includes dangerous winds, heavy and intense rainfall, storm surges, coastal flooding and landslides. Let’s consider how these hazards threaten people and the environment.

High Winds

Powerful wind speeds of 119 to 250km per hour can cause a range of hazards. During a storm, high winds can uproot trees, which can lead to damaged power lines. Buildings can be damaged if they are poorly built, and debris blown around by the wind can cause injuries and even deaths. Understanding the windspeed of the cyclone is the best way for scientists to determine the extent of the damage that will be caused.

Intense Rainfall

As cyclones form and move across the ocean, they gather a vast amount of moisture. As the cyclone makes landfall, this moisture falls as intense rain, which can lead to flooding of properties. Fast-flowing water can sweep people away, increasing loss of life. Due to satellite tracking of the storm, weather forecasters can predict how much rain will fall, allowing residents to prepare.

Storm Surges

A storm surge is influenced by the introduction of low pressure when a cyclone is formed. Combined with the high winds of the cyclone, the increased sea level is forced towards the land, posing a severe risk of flooding to coastal areas. Beaches can be eroded and habitats destroyed. Storm surges also threaten farmland further inland and freshwater sources such as lakes.

Coastal Flooding

Coastal areas are at high risk during a tropical storm event due to the intense rain and threat of storm surges. Flooding is a serious risk to people and property, as well as the farming and tourism industries. Salt water can damage farmland and freshwater supplies, which can have secondary social, economic, and environmental impacts.

Landslides

Saturated soil from intense rainfall can lead to physical hazards in areas of high relief, [insert definition: height and shape of land], as well as areas of lowland. Saturated soil is very heavy, and on steep slopes, this wet soil begins to slide down. Soil that is layered on impermeable rock slides very easily when saturated, leading to the devastation of settlements at the bottom of slopes. Rivers can also be blocked by soil debris, which further increases the risk of flooding.

Impacts of Cyclones

Tropical storms are most commonly measured on the Saffir-Simpson Hurricane Wind Scale. Each level of the scale poses different hazards. A tropical cyclone which registers above a Category 3 has the potential to cause severe damage and pose a serious risk to life.

Saffir-Simpson Hurricane Scale