Water Cycles

Question 1

Dynamic equilibrium

Answer 1

where there is a balance between inputs and outputs

Question 2

Closed system

Answer 2

there is a transfer of energy into and beyond the system but no matter

Question 3

Open system

Answer 3

both energy and matter transfer freely into and out of the system

Question 4

Oceanic water

Answer 4

5 oceanic bodies containing 72% of the earth surface area

Question 5

Cryospheric water

Answer 5

made up of ice sheets, glaciers and permafrost

Question 6

Terrestrial water

Answer 6

rivers and lakes, 52% of the freshwater on earth is stored in lakes and 1% in rivers

Question 7

Atmospheric water

Answer 7

most common form is water, absorbs and reflects solar radiation

Question 8

What can a small increase in water vapour do?

Answer 8

increase atmospheric temperatures (positive feedback)

Question 9

Flood

Answer 9

a body of water that rises to overflow land that is normally submerged

Question 10

Drainage basin

Answer 10

an area of land drained be a river and its tributaries

Question 11

Lag time

Answer 11

the time taken from the peak rainfall to peak discharge

Question 12

Base flow

Answer 12

the amount of water that would be in the river without the storm flow

Question 13

Storm flow

Answer 13

overland flow and throughflow

Question 14

Flashy hydrograph

Answer 14

short lag time, high peak discharge, sleep rising limb and sleep falling limb

Question 15

Subdued hydoggraph

Answer 15

long lag time, low peak discharge and a gentle rising limb

Question 16

Monsoon

Answer 16

a seasonal reversal in wind direction that brings a period of intense rainfall

Question 17

Features of a river:

define 7 terms

Answer 17

• source: where water from surface runoff or from rock percolation, first forms a water channel to transfer water to a new store downstream
• tributary: smaller channel which joins the main channel and contributes to the total flow
• confluence: where rivers meet and join up
• flood plain: an area in the lower course which regularly floods during events of higher flow
• water shed: the border of the drainage basin
• estuary: governed by the tide, as sea and fresh water meet, the flow slows down and accretion occurs
• mouth: where the river meets the ocean

Question 18

Features of a drainage basin:

define terms and sort into inputs (1), flows (7), stores (4) and outputs (3)

Answer 18

INPUTS:
-precipitation: water that falls to the earth in any form
FLOWS (transfers or fluxes):
-channel flow: precipitation directly entering the river channel
-stem flow: water reaches the ground by flowing down trunks or stems or by dropping off leaves
-overland flow: also called surface runoff, occurs during heavy rainfall when the ground is saturated or if surfaces are impermeable, very rare except in urban areas
-groundwater flow: water in this zone moves laterally (sideways) at a very slow rate. it transfers water to the river through the river bed and banks long after rainfall events
-percolation: a vertical movement of water from above the water table to below the water table, if the bedrock is impermeable, e.g. granite, no percolation occurs
-infiltration: the passage of water vertically into the soil. this does not occur if soil is saturated
-through flow: water flows laterally through the soil to the channel, mainly along ‘‘pipes’’ caused by animal activity or growth of plant roots
STORES:
-interception: raindrops fall on vegetation, preventing it from reaching the soil and river
-soil moisture: water stored in the soil above the water table
-surface water: water stored on the surface, e.g. lakes and rivers
-aquifers (groundwater): water stored below the water table in saturated soil or rock
OUTPUTS:
-evaporation: moisture lost into the atmosphere by the sun’s heat and wind
-evapotranspiration: biological process where water is loss as vapour through small pores in plant’s leaves
-river discharge: fresh water enters the ocean and so leaves the drainage basin

Question 19

the drainage basin is a……………..system:

Answer 19

open system as matter (water) enters and leaves through the system barrier and energy is input

Question 20

discharge is

Answer 20

River discharge is the volume of water flowing through a river channel. This is the total volume of water flowing through a channel at any given point and is measured in cubic metres per second (cumecs). The discharge from a drainage basin depends on precipitation, evapotranspiration and storage factors.