Floods and Their Causes

What is the second most common natural disaster?

• Fire

• Earthquake

• Tornado

• Hurricane

What are the conditions that can cause flooding?

• Deep snow and heavy rain

• Frozen ground and heavy rain

• Deep snow and sudden warmer weather

• All of the above

When does deep snow alone rarely cause floods?

• When it occurs with heavy rain

• When it occurs with sudden warmer weather

• When it occurs on frozen or very wet ground

• When it occurs on dry ground

What happens when rivers are already at their full capacity of water?

• They freeze and cause flooding

• They overflow and flood the surrounding land

• They evaporate and cause flooding

• They remain stable

What can ice-covered rivers lead to?

• Flooding upstream

• Flooding downstream

• Formation of ice dams

• All of the above

What can cause the water behind an ice dam to rise and flood the land upstream?

• Cracks in the ice

• Melting of the ice

• Formation of large ice pieces

• Breaking of the dam

What can happen if a large human-made dam breaks or fails to hold the water?

• Flooding downstream

• Flooding upstream

• Formation of ice dams

• None of the above

What is the destructive force of unleashed dam waters compared to?

• A strong wind

• A heavy rain

• A great tidal wave

• An earthquake

What do scientists know about when floods are likely to occur?

• The exact time and location

• The exact cause and effect

• The exact magnitude and duration

• The likely conditions and factors

How can knowledge of why floods happen help reduce the damage they cause?

• By preventing deep snow

• By building stronger dams

• By predicting exact flood occurrences

• By taking preventive measures