Please enable JavaScript.
Coggle requires JavaScript to display documents.
Causes of floods part 2 - Coggle Diagram
Causes of floods part 2
How can rainfall lead to river flooding?
When the thunderstorm occurs, it will lead to the increase in the amount of water.
If the water level in the river is at its peak, further increase in the amount of water will overflow the land.
Land that is normally dry will be flooded.
Such storms bring in heavy rain and strong winds.
Tropical storms may develop into tropical cyclones, also known as hurricane and typhoon. When tropical cyclones occurs, there will be an increase in rainfall.
Since most tropical cyclones occurs near the coasts, the increase in the amount of water into the water bodies will lead to coastal floodings.
A tropical storm is a storm with high intensity and prolonged rainfall.
How can snowmelt lead to flooding?
During winter, ice and snow melt and causes surface runoff.
When temperature increases, the ice and snow melt.
The snowmelt flows over the and into rivers, leading to river flooding. This causes the river to overflow and flood the surrounding areas.
How does storm surge lead to coastal flooding?
During a storm, strong winds push water towards the coast and create huge waves, giving rise to storm surge.
Due to the force of huge waves moving inland, coastal land that was once dry will be flooded.
How does failure of man-made structure lead to river flooding?
Levee failure
High amount of water in the river will overflow the levees and cause collapse of levees. Water will flood the surrounding areas.
Floodwall
Floodwalls may collapse due to overflowing of banks. This will increase the water level. With the increase of water level, there is no protection against the rise in water level and flooding will occur.
Dam failure
When there is dam failure, excess water will flow downstream.
Large amounts of fast flowing water overflow the banks and cause flooding.