Vocabulary 1
overflows of large amounts of water onto land that is normally dry
floods
Define snowmelt
Surface runoff that results from melting snow
What's an example of human causes of floods?
Failure of man-made structures including dams, levees, and floodwalls
What is a man-made device that helps generate hydropower and regulate the amount of water flowing in a river?
Dam
droplets of water that fall to the ground
rainfall
A sudden rise of the sea level in which water is piled up against a coastline beyond normal high-tide conditions is called...
rain intensity
This Dam Disaster was one of the biggest dam failures in history.
a. Shanghai
b. Xinjiang
c. Guangzhou
d. Banqiao
Banqiao
Break down the natural causes of coastal floods and river floods. Differentiate which causes which.
Coastal floods: Storm surges and tsunamis
River floods: Prolonged and intense rainfall, snowmelt
The rate of which rain falls is called...
rain intensity
Refers to the number of times a certain amount of rain falls within a period of time.
(Not necessary for the points) For example, at Changi Singapore, daily rainfall exceeding 70 millimetres occurred twice in February 2016.
Outline the characteristics of a flash flood
Takes place suddenly and lasts for a short period of time.
Caused by heavy rainfall. Recognized by its quick rise in water.
Rain intensity is measured in _____________.
A. Millimetres per hour
B. Millimetres per second
C. Centimetres per minute
D. Centimetres per hour
Millimetres per hour
Define channel capacity
The volume of water that can be held in the channel of a river without overflowing
Define levee
Raised banks on either side of the river channel.
Outline the different characteristics of river floods
Occur when the amount of water in a river channel exceeds the limit of the channel.
Water overflows the riverbanks and onto the floodplain.
Causes include snowmelt, heavy rain, and dam failure.
Sea level refers to the _______________ between the mean low tide and mean high tide.
Midpoint
Define permeability
The ease with which water can infiltrate or seep into the ground
Define floodplain
Low-lying land on either side of the river channel.
Outline the important characteristics of a coastal flood
Occur in low-lying coastal areas
Caused by intense storms such as tropical storms, typhoons, cyclones, and hurricanes
Also caused by tsunamis, huge ocean waves caused by underwater earthquakes
Characterized by storm surges
Concrete surfaces are ________, meaning that the water is unable to infiltrate the ground
impermeable