River Flooding - Causes

Emily Gibson
Mind Map by , created almost 6 years ago

GCSE Geography (Rivers) Mind Map on River Flooding - Causes, created by Emily Gibson on 12/22/2013.

43
1
0
Tags
Emily Gibson
Created by Emily Gibson almost 6 years ago
GCSE Geography - Causes of Climate Change
Beth Coiley
Characteristics and Climate of a hot desert
Adam Collinge
Volcanoes
1jdjdjd1
Life in Germany
Ben C
French Revolution quiz
Sarah Egan
River landforms
Emily Gibson
Rivers Flashcards
Tom Mitchell
Transportation Processes
Alex Collins
Geography Coastal Zones Flashcards
Zakiya Tabassum
Using GoConqr to study geography
Sarah Egan
River Flooding - Causes
1 Prolonged rainfall
1.1 Long period of rain - soil become saturated
1.2 Further rainfall can't infiltrate - increases run-off into rivers
1.2.1 Increases discharge
2 Heavy rainfall
2.1 A lot of runoff - increases discharge quickly
3 Snowmelt
3.1 A lot of snow or ice melts into river in short space of time
3.1.1 Increases discharge quickly
4 Relief
4.1 If steep sided valley - water will reach river channel much quicker
4.1.1 Increases discharge quickly
5 Geology
5.1 If river in area of impermeable rock, more water flowing on surface
5.2 More runoff - risk of flooding higher
6 Deforestation
6.1 Trees take in water (leaves, roots)
6.2 Cutting down trees increases volume of water that goes to river
6.2.1 Increases discharge
6.3 Causes soil errosion
6.4 So soil washed away - raises river bed
6.4.1 Reduces volume of water river can hold
7 Urbanisation
7.1 Buildings with impermeable surfaces (roads, concrete)
7.1.1 Increases surface runoff
7.1.1.1 Increases discharge quickly

Media attachments