CONTESTED PLANET UNIT 3

Topic 2: Water Conflicts

Topics to be learned

• The geography of water supply• The risks of water insecurity• Water conflicts and the future

Water lot of water?What physical affect water supply?

1 thing we know

2 things we think we

know

2 things we think we

know

3 things we want to find

out

3 things we want to find

out

3 things we want to find

out

DM – June 2011

What we know Triangle

WATER QUIZ…

1. Water we use today is the same as has been used for millions of years.

2. Which is the driest place on the earth?

3. What percentage of the world’s water is fresh?

4. What percentage of the world’s water is available for human use?

5. All of London’s water comes from the Thames.

6. How much water is lost in the UK through leaky pipes?

7. How much more rain do the wettest areas of the UK get than the driest areas?

8. How many people in the world do not have access to clean drinking water?

9. Which country uses the most water per capita?

10. Water wars are conflicts between countries across oceans.

1. Water we use today is the same as has been used for millions of years.

The hydrological cycle is a CLOSED system – nothing enters, nothing leaves…

2. Which is the driest place on the earth?

3. What percentage of the world’s water is fresh?

4. What percentage of the world’s water is available for human use?

5. All of London’s water comes from the Thames.

We also obtain water from AQUIFERS across the south of England.

6. How much water is lost in the UK through leaky pipes?

7. How much more rain do the wettest areas of the UK get than the driest areas?

The Western Highlands get 500cm. East Anglia gets 50cm.

8. How many people in the world do not have access to clean drinking water?

9. Which country uses the most water per capita?

Turkmenistan has an arid climate, a poor infrastructure and inefficient usage.

10. Water wars are conflicts between countries across oceans.

Water wars can occur within a country e.g. between states in the USA. They are more common between countries e.g. Israel and Palestine.

Nerdy facts about water….• 71% of the world is covered by water• Only 0.0296% of the water on earth is used by humans

(rivers, freshwater lakes, ground water and soil store)• If water was shared out equally amongst the 7+ billion

people on earth there would be enough for each person to have 5 million litres

• But 4 billion live in areas with only 25% of the world’s annual rainfall

• The UN says 1 billion lack access to fresh drinking water• More than 0.5 billion face water shortages every day• And the world population increases by approximately 80

million a year!

• Every 15 seconds a child dies from water borne diseases

• Half of the world’s lakes and rivers are badly polluted

• Half of the world’s rivers no longer flow all year• 12% of people consume 85% of the world’s

water• Population growth by 2025 will demand a 20%

increase in water supplies

The risks of water insecurityWhat are the potential implications of an increasingly ‘water insecure’ world?

Water supply problemsIncreasing water shortages

may be more important than energy shortages- because

there is no alternative!

Water conflictsWhere demand exceeds supply and no effective management operates, then there will be conflicts between

the various players involved

Water geopoliticsThe conflicts between nation states, despite the international agreement called the Helsinki Rules designed to create more equitable use of water

extending across boundaries

Water transfersOf this precious resource by either diverting the actual river, or using canals . Long carried out at a small scale but increasingly over larger

distances, and even transboundary

Do you know the terms of the hydrological cycle?

- Closed System - Groundwater flow - Stores - Evaporation - Flows - River Flow - Inputs - Surface Runoff - Outputs - Through flow - Blue water flow - Green water flow - Evapotranspiration- Percolation - Precipitation - Infiltration

a) Climate•Climatic zones are critical in determining water storage in any of then earth’s reservoirs•Annual temperature and rainfall patterns in a place determine the availability of water•Precipitation (rain, hail, sleet and snow) varies with latitude•Equatorial/ tropical areas (up to 15 degrees N or S of equator) have higher rainfall than temperate(40-60 degrees North and South) / arctic areas.•High altitude areas have snowpack water reserves released in late spring.•Monsoon areas have one main peak, equatorial areas two peaks.•Other factors like proximity to oceans and prevailing winds distort latitudinal divisions•Seasonality is of great importance in an area – eg in Vancouver Canada summer evapotranspiration is higher than precipitation so there is soil moisture deficit but in winter there is more precipitation than evapotranspiration so the soil moisture increases and recharges……see graph in Pearson •So location can determine the relative size of the input of precipitation and the output by evaporation, transpiration, (as well as runoff to the sea/lake and abstraction).

1.The geography of water supply - physical influences P 32-34 Pearson

ClimateMonsoon Climate Global Climate Circulation

El Nino

b) River systems transport this water. • Discharge/flows increase downstream as tributaries enter.• The time it takes from the peak precipitation to fall to reach

the peak river discharge (lag time) is determined by – Type of precipitationAntecedent (previous) rainfallLand useSize and shape of drainage basinRelief of catchmentDrainage patternAnd geology • The relationship between water inputs and outputs is water

balance• Seasonal changes in temperature/precipitation can create

distinctive river regimes.

River SystemsDischarge = Cross Sectional area x Velocity

This increases down stream

Streamflow can only occur when the water stores in the drainage basin are capable of releasing water, and when there is direct surface runoff.

In order to understand the streamflow pattern across a year (called the river regime) you have to understand the changing balance of three key variables – evapotranspiration, soil storage and groundwater storage.

This dynamic relationship can be expressed as the water balance equation:Precipitation (P) = streamflow (Q) + evapotranspiration (E) +/- changes in storage (S)

River Regimes Vary and so does water Supply

c) Geology• Surface drainage occurs on rocks which are impermeable such as

granite and clay as they are aquicludes• Permeable rocks like chalk and some sandstones store water, called

aquifers.• The rate of infiltration of water into the soil or of percolation into rocks

depends on the porosity and permeability of the material. Sand has large pores and this allows water to infiltrate quickly at a rate of about 200mm/hr whilst in clay the rate is only about 5mm/hour. Both materials are porous (the % of the material that is air spaces or pores) but the sand is much more permeable.

• [Perviousness is where water can drain through cracks in the rock – limestone is a pervious rock with many joints and bedding planes].

• Soil water is important because it affects upward and downward movement of water (and dissolved nutrients). Drainage depends on the balance between the water retention capacity (water storage In the soil) and the infiltration rate. This is controlled by the porosity and permeability of the soil. Clays have many micropores which can retain water for long periods – giving it a high water retention capacity but reducing its infiltration rate. Sands have fewer but much larger macropores which permit more rapid infiltration.

Geology1. Impermeable Rocks = High Drainage density

2. Permeable rocks = water passes under ground

3. Aquifers e.g chalk