Hydrosphere: How to do a Hydrograph Question

Question 1

What describe points can you do for a hydrograph?

Answer 1

Lag time, peak flow, steep/gentle rising limb, steep/gentle recession limb

Question 2

What is Lag time?

Answer 2

It is the time difference between maximum rainfall and peak discharge

Question 3

What is Peak flow?

Answer 3

The point of maximum discharge AND GIVE TIME

Question 4

Give 3 ways that a steep rising limb can be caused (vegetation, rock, soil)

Answer 4

-no vegetation to intercept rainfall
-impermeable rock means there will be increased overland flow
-soil reaching saturation level increases surface runoff

Question 5

4 ways that there could be a gentle rising limb? (opposite of steep basically)

Answer 5

-vegetation can intercept rainfall
-permeable rocks allows for percolation to occur
-water can infiltrate into the soil
-little amount of rainfall

Question 6

What can a steep recession limb be caused by?

Answer 6

Rainfall stopping

Question 7

3 things that can cause a long lag time? (tributaries, sloping, large/small)

Answer 7

• few tributaries mean that the water travels slower towards the main river
  -a gently sloping valley means the movement of water will be slower
• a large drainage basin means that water takes longer to reach the river

Question 8

3 things that can cause a short lag time? (tributaries, sloping, large/small)

Answer 8

• A basin with many tributaries means that water travels quickly towards the main river
  -A steep valley means that water will be able to move faster
  -A small drainage basin means water doesn’t take long to reach the river

Question 9

What is a long lag time?

Answer 9

> 5 hours

Question 10

What is a short lag time?

Answer 10

<5