Tsunamis affect the Earth in several ways: on land, they cause habitat disruption, flooding and alter landscapes, and produce deadly, dangerous rip currents at sea. The extent of damage tsunamis cause varies depending on the storm size and location of landfall. Tsunamis potentially cause vast flooding in low-lying land areas, and alter natural waterways, changing the shape and flow of rivers and streams.
Tsunamis form in tropical waters. They generate strong currents prior to making landfall, which increase in speed and strength as they head towards shore. Tsunamis form from large underground earthquakes in the ocean. These earthquakes generate smaller but powerful waves ahead of the tsunamis. The forceful movement of these waves changes the landscape beneath the surface of the water too, destroying coral reefs, uprooting aquatic vegetation and displacing organisms as they approach shore.
After crashing, tsunamis create devastating impacts. They take the lives of humans and animals, and often generate substantial amounts of debris. Tsunamis cause significant economic disruption in addition to creating environmental impact. They disrupt the livelihoods of fishermen, sailors and others relying on maritime activities for income. Tsunamis also impact agricultural output of coastal areas upon making landfall. They bring excessive amounts of salt to shore, which in turn alters the composition of coastal soils and often inhibits growth.