1.4 The Human Impact Flashcards
How does deforestation affect the risk of floods?
It reduces interception and evapotranspiration, increasing surface runoff and flood risk.
How does afforestation impact the risk of floods?
It increases interception, evapotranspiration, and soil infiltration, reducing flood risk.
How does urbanisation impact the risk of floods?
It reduces infiltration, increasing surface runoff and flood risk.
How does rock type impact the risk of floods?
Impermable rocks decrease infiltration, increase
What are the main natural causes of river floods?
Intense rainfall, snowmelt, saturated soils, and steep slopes.
What are recurrence intervals in flood prediction?
The average number of years between floods of a certain size
How is flood risk assessed?
By using historical data, hydrological models, and satellite imagery.
What are the benefits of early flood warnings?
They allow evacuation, protection of property, and reduced loss of life.
What is a dam, and how does it prevent floods?
A structure that holds back river water, releasing it gradually to control flooding.
What are the disadvantages of dams?
Expensive, disrupts ecosystems, and can displace communities.
What is river straightening?
Artificially altering a river’s course to increase velocity and reduce flood risk.
What are the drawbacks of river straightening?
It can increase flood risk downstream and cause erosion.
What are levees?
Raised banks along a river designed to prevent overflow.
What are the risks of levees?
They can fail during extreme floods, causing catastrophic flooding.
What is floodplain zoning?
Restricting development in high-risk flood areas.
What are the benefits of floodplain zoning?
Reduces damage to buildings and infrastructure.
How much of Thailand was affected?
Over 65 provinces were flooded, covering 20,000 km².
What caused the 2011 Thailand floods?
Heavy monsoon rains, deforestation, and poor drainage systems.
What were the economic impacts of the 2011 floods in Thailand?
Over $50 billion in damages, disrupting global manufacturing supply chains.
What were the social impacts of the 2011 floods in Thailand?
Over 800 deaths, 15 million people affected
How did the Thai government respond to the floods?
Closed the Dams, Gates
