• Tsunamis can change whole landscapes and wreck communities.mer houleuse image by Unclesam from Fotolia.com
  
  Tsunamis are huge sea waves which are typically caused by abrupt changes to the floor of a body of water, such as those created by an earthquake. When a tsunami strikes an area, its effects can be devastating in the short-term, destroying buildings and killing or injuring people and animals. A tsunami also causes long-term damage to an area, since a country's infrastructure can be severely affected and whole communities may be drastically altered.
  
  

Human Fatalities

• Tsunamis can lead to a staggering number of human casualties if they make landfall in populated areas. Settlements near water such as fishing villages are particularly at risk, as waters gush over whole areas and buildings collapse. Polluted waters and poisoned drinking wells can add to these deaths in the tsunami's aftermath. The tsunami which hit parts of South Asia in 2004 caused over 50,000 deaths in Sri Lanka alone, according to the Practical Action website. In addition to these fatalities, tsunamis damage communities, leaving children without parents and in some cases wiping out generations of youths.
  
  

Property Damage

• Tsunamis wreck buildings, both from the high-energy impact of tsunami waves on structures and from the effects of erosion on the metal components of buildings. Debris from fallen structures can also later damage other areas, while in the aftermath of the tsunami, raging fires can cause further destruction. The cost of reconstructing whole towns hit by a tsunami can be extremely high. For instance, after the South Asia tsunami of 2004, the cost to rebuild in Indonesia was estimated to be around $4.4 billion, according to the Guardian newspaper website.
  
  

Livelihoods Disrupted

• Following a tsunami, many survivors find that their livelihoods have been ruined by the effects of the disaster. Homes will have been destroyed, leaving many people without shelter. Agricultural businesses are affected by the devastation inflicted on farmland, such as the deaths of livestock, while small fishing businesses may not be able to operate for some time.
  
  

Landscapes and Ecosystems

• The landscape itself will likely be damaged in the wake of a tsunami. The force of a tsunami can displace hazardous chemicals and waste products to new areas, leading to the poisoning of marine life. Environments such as coral reefs can be adversely affected, for example by the sudden appearance of large amounts of sediment which can smother the flora found in these areas. Whole beaches may be left without sand. Flora and fauna in areas hit by the tsunami may be killed with trees being literally uprooted by the waves.