Physical + Human Causes Of Floods

Question 1

Phys- Precipitation

Answer 1

Rain falls into river channels. This increases the river’s discharge and evetually the river may overtop its banks. Toreential rainfall can make this happen very quickly and this can lead to a flash flood

Question 2

Phys- Geology

Answer 2

Impermeable rocks and rocks that are easily easily saturated encourage rain water to runoff over land and into river channels. This means more water enters the river channel and this makes flooding more likely.

Question 3

Phys- relief/ steep slopes

Answer 3

In mountain environments steep slopes encourage a rapid transfer of water towards river channels which makes flooding more likely

Question 4

Human- Urbanisation

Answer 4

Building on a floodplain creates impermeable surfaces. water is transferred quickly to drains and then from the drains into the urban river channels which makes flooding more likely

Question 5

Human - Deforestation

Answer 5

When trees are removed less water is intercepted and stored which means more water reaches the floor and can be transferred into river channels

Question 6

Human - Agriculture

Answer 6

Farming means large areas of soil are left exposed to rain fall and areas of land that have vegetation and cannot intercept rainfall. This increases surface run off and water being transferred into river channels