Environmental Impacts

Cyclones generally have negative impacts upon the environment. The impacts tropical cyclones have on the environment include loss of habitat, changes to the biodiversity levels, erosion, effects on water quality. Tropical cyclones are known to bring destructive winds, and heavy rain with flooding which creates storm surges, causing inundation in low-lying areas. However, the most common features of a tropical cyclone is destructive winds and heavy rainfall that can lead to flooding.

The most dangerous element of a cyclone that poses the most threat to the environment is its strong gusts of winds. These winds of a cyclone can cause widespread damage to the environment as it can throw rubble and debris everywhere, which can cause damage to trees, habitats and can affect sewerage and sanitation systems. The destructive winds that accompany tropical cyclones are also capable of causing serious erosion and wiping out all vegetation and forestry.

Another potentially dangerous hazard associated with tropical cyclones is storm surges or coastal inundation. A storm surge is an abnormal rise of water due to a tropical cyclone, and is caused by a combination of strong winds forcing water onshore and the lower atmospheric pressure in a tropical cyclone. If the storm surges occur simultaneously with the high tide, the area affected is quite often extensive.

Heavy rain can create severe impacts by causing floods, mudslide and landslides. Once tropical cyclones move inland, they often degenerate into rain depression. This drops heavy rain onto regions and causes floods. Since tropical cyclones form over warm tropical waters, they tend to contain enormous amounts of moisture and can produce heavy rainfall over extensive areas. Although this rain may be beneficial to otherwise dry regions, in Australia, too much can cause flooding. This flooding can wreak havoc over vast areas, as it can inundate land, isolate communities and destroy infrastructure.

Social Impacts

Tropical cyclones also leave behind many social impacts, particularly on the people directly affected. Cyclones can claim lives and often, many people are harmed as a consequence of storm surges, destructive winds and flooding. Few homes remain intact after tropical cyclones, causing many individuals to suffer from nightmares, traumatized by the disaster. In some severe cases, victims of the disaster may be susceptible to psychological stress, depression and mental illness, as a result from having lost loved ones and property, and the events that unfold during the aftermath of the cyclone.

Economic Impacts

Tropical cyclones can have economic effects on society. They are one of the most financially-damaging natural disasters, costing the Australian economy hundreds of millions of dollars in property damage and insured losses. On top of this, transportation and communication infrastructure may have been destroyed, thus hindering clean-up and rescue efforts. The worst cyclones of Australia have caused billions of dollars of damage and many fatalities. Such expenses needed to repair the destruction caused by the cyclone would ultimately send the country’s wealth and economy into turmoil.

• The aftermath of Cyclone Tracy, which hit Darwin in the early hours of Christmas day in 1974, had a major impact on the economy. Cyclone Tracy destroyed up to 80% of all buildings and caused enormous damage to infrastructures. A total of $950 million was the estimate cost of the disaster and the population of Darwin, which was 45 000 in 1974, went down to 10 500, many evacuees having not return. This majorly impacted the local economy in a negative way.
• In another case, Cyclone Larry had greatly affected infrastructures, causing severe damage and impacting on all townships in the Innisfail region. Data on the damage inflicted are organized below: