EQ1

Question 1

Closed system

Answer 1

When there is a transfer of energy but not matter between the system and its surrounding. There are no external inputs/outputs, any inputs come from within the system.

Question 2

Flows (fluxes)

Answer 2

Measurements of the rate of flow between stores.

Question 3

Processes

Answer 3

Are the physical mechanisms such as evaporation that drive the flows of water between the stores.

Question 4

Stores (stocks)

Answer 4

Reservoirs where water is held, e.g. oceans.

Question 5

Blue water

Answer 5

Water that is stored in rivers, streams, lakes and groundwater in liquid forms (visible).

Question 6

Green water

Answer 6

Water stored in the soil and vegetation (invisible).

Question 7

Precipitation

Answer 7

The input into a drainage basin system. It includes all forms of moisture entering: hail, snow, dew, frost, sleet and rain.

Question 8

Interception storage

Answer 8

The storage of water when it lands on vegetation (or structures like buildings) before it reaches the soil. It is a temporary store before evaporation or stemflow.

Question 9

Surface storage

Answer 9

The storage of water on the surface including puddles, ponds and lakes.

Question 10

Soil water (sub-surface) store

Answer 10

The storage of water in soil. Water is held in the small gaps between soil particles.

Question 11

Groundwater store

Answer 11

The storage of water in the ground rocks of permeable rock. The water is held in cracks (limestone) bedding planes (sedimentary rock) or pores (chalk). Rocks with lots of water storage are called aquifers.

Question 12

Channel store

Answer 12

The storage of water in the river channel. As water is being transported to the sea it is a store of water.

Question 13

Vegetation store

Answer 13

The storage of water in the vegetation. Plants and trees take up water through their roots and water is stored here.

Question 14

Surface run-off

Answer 14

The horizontal flow of water over the surface of the land either in little channels or over the whole surface – this is usually a quick flow.

Question 15

Stemflow

Answer 15

The downwards flow of water moving downwards from interception storage to the surface.

Question 16

Soil (sub-surface) throughflow

Answer 16

The horizontal flow of water moving through soil (between the particles) towards the river.

Question 17

Infiltration

Answer 17

The downwards movement of water from the surface into the soil.

Question 18

Percolation

Answer 18

The downwards movement of water from the soil to the permeable ground rock.

Question 19

Groundwater (base) flow

Answer 19

The horizontal movement of moving through the rocks (cracks/bedding planes/pores) slowly towards the river. This is the movement of water below the water table sideways to the river.

Question 20

River channel flow out to the basin’s exit (lake, reservoir, ocean)

Answer 20

The movement of water in the river channel moving towards the sea.

Question 21

Evaporation

Answer 21

The output of water when water is heated and turned from a liquid into a gas.

Question 22

Transpiration

Answer 22

The output of water where moisture is taken into plants through their roots, moved to the leaves by capillary action and then evaporates from the leaves into a gas.

Question 23

Evapotranspiration

Answer 23

The combined output of water from evaporation and transpiration.

Question 24

River discharge

Answer 24

The output of water from a river channel out to sea.

Question 25

Orographic (relief) rainfall

Answer 25

As the moist air is forced to rise on the windward side of the mountain, rainfall occurs as a result of adiabatic cooling (when the volume of air increases but there is no addition of heat), and condensation to dew point. The air, without much water left in it, is then drawn over the mountains where it descends and is adiabatically warmed by compression. This leads to a very dry ‘shadow’ area.

Question 26

Frontal (cyclonic) rainfall

Answer 26

This happens when warm air, which is lighter and less dense, is forced to rise over cold, sense air. As it rises, the air cools and its ability to hold water vapour decreases. Condensation occurs and clouds and rain form.

Question 27

Conventional rainfall

Answer 27

When the land becomes hot, the air above it becomes warmer, expands and rises. As it rises, the air cools and its ability to hold water vapour decreases. Condensation occurs and clouds develop. If the air continues to rise, rain will fall.

Question 28

Water budget

Answer 28

Water budget reflects the natural annual balance between inputs and outputs in a given river area. The formula used is: P=Q+E+/-S where:
Precipitation (P) = Channel discharge (Q) + Evapotranspiration (E) +/- Change in Store (S).
Whatever falls as precipitation should be balanced by the other components, otherwise it means there might be flood or drought.

Question 29

Field capacity

Answer 29

The normal amount of water that can be held in the soil.

Question 30

Potential evapotranspiration

Answer 30

The amount of water that could be lost by evapotranspiration if there was sufficient moisture available.

Question 31

Actual evapotranspiration

Answer 31

The amount of water that is lost through transpiration (release from leaves) and evaporation (heating of water on surfaces) to the atmosphere.

Question 32

Soil moisture surplus

Answer 32

Occurs when the soil moisture store is full and there is excess water available for plants, runoff and recharge. (Prec>E/T).

Question 33

Soil moisture utilisation

Answer 33

Occurs when moisture from the soil stores is being used by vegetation/humans as the precipitation rate is less than E/T. (E/T > Prec).

Question 34

Soil moisture recharge

Answer 34

Occurs when moisture from precipitation infiltrates and percolates in the stores to repay the soil moisture utilisation/deficit. (Prec>E/T).

Question 35

Soil moisture deficit

Answer 35

There is not enough water left in the soil to match potential e/t. Rivers run dry and drought ensues. (P E/T > Prec for a prolonged period).

Question 36

Water budget/balance graphs

Answer 36

• Water Budget/Balance graphs provide a direct comparison of natural water supply and demand and the impact this has on soil water permeability.
• They help us identify where P>ET = Possible balance (flood) and where P

Question 37

River regime

Answer 37

River regimes indicate the annual variation of discharge of a river at a particular point and is measured in cumecs.

Question 38

Glacier melt (river regime)

Answer 38

Glacier melt - European mountain rivers have a high-water period (July-August) when glaciers feeding them melt most rapidly.

Question 39

Snow melt (river regime)

Answer 39

Snowmelt - melting of snow cover either in mountainous areas during early summer or over the Great Plains of North America in spring.

Question 40

Tropical seasonal rainfall (monsoonal) (river regime)

Answer 40

Tropical seasonal rainfall (monsoonal) - in tropical areas, evapotranspiration tends to be stable (high) but summer rains cause a peak.

Question 41

Oceanic rainfall/evapotranspiration (river regime)

Answer 41

Oceanic rainfall/evapotranspiration - in many oceanic areas of Europe, rainfall is evenly distributed but high evapotranspiration in summer leads to low run-off.

Question 42

Hydrograph

Answer 42

A hydrograph is a graph showing variation in discharge (volume) of water at a given point over a short period of time, normally an individual storm (few days).