Hydrographs and flooding (needs doing)

Question 1

Delayed Hydrographs

Answer 1

-shallower rising limb
-shorter lag time
-lower peak discharge

Caused by:
Human
-parks (more trees so more interception)

Physical
-rock type permeable
-shallow sided valley relief so it takes longer for water to reach the river so longer lag time

Question 2

Flashy hydrographs = more flood risk

Answer 2

-steep rising limb
-short lag time
-high peak discharge

Caused by:
Human
-urban areas of concrete that increase surface runoff off and shorten lag time
-deforestation less trees less interception more surface run off shorter lag time

Physical
-steep relief ( valley shape) water runs down the valley high surface run off shorter lag time
-rock type impermeable rock