River Discharge Flashcards
Hydrographs Show the Change in River _____________.
Discharge.
River Discharge is Simply the __________ of Water that Flows in a River Per Second. What’s it Measured In?
Volume.
M(Cubed)/s.
What is Peak Discharge?
The Highest Discharge in the Period of Time.
What is Lag Time?
The Delay Between Peak Rainfall and Peak Discharge.
What is Rising Limb?
The Increase in River Discharge as Rainwater Flows into the River.
What is Falling Limb?
The Decrease in River Discharge as the River Returns to its Normal Level.
Lag Time Happens Because Most Rainwater doesn’t Land Directly in the River ___________.
Channel.
If More Water Flows as ____________, the Lag Time will be Reduced, Meaning Discharge will ____________ and the Hydrograph will be Steeper.
Runoff…Increase…
Physical Factors that Affect Lag Time, Discharge and the Shape of Hydrographs?
- Geology.
- Soil Type.
- Slope.
- Drainage Basin Type.
- Antecedent Conditions.
Human Factors that Affect Lag Time, Discharge and the Shape of Hydrographs?
- Urbanisation.
- Deforestation.
How does Geology Affect Lag Time, Discharge and the Shape of the Hydrograph?
Water can’t Infiltrate into Impermeable Rocks, so there’s More Runoff.
How does Soil Type Affect Lag Time, Discharge and the Shape of the Hydrograph?
More Impermeable Soils can’t Absorb as much Water as Sandy Soils.
How does Slope Affect Lag Time, Discharge and the Shape of the Hydrograph?
The Steeper the Slope, the Less Infiltration and the Higher the Runoff.
How does the Drainage Basin Type Affect Lag Time, Discharge and the Shape of the Hydrograph?
Circular Drainage Basins have a Shorter Lag Time and Higher Discharge than Narrow Basins Because Water Reaches the Main River Channel at the Same Time.
How do Antecedent Conditions Affect Lag Time, Discharge and the Shape of the Hydrograph?
Previously Wet or Cold Weather can Increase Runoff Because Water can’t Infiltrate Saturated or Frozen Soil.
