water world

-consists of all water on the planet e.g sea, river, lakes and rocks and soil, in living things and in the atmosphere as liquid (water) solid (ice) gas (vapour)

-the water goes round and round- none is added or lost so the earth doesnt get drier or wetter

think of the earth as having stores e.g sea, lakes

and between each store water flows by either transpiration, water run off, through flow, evaporation, infiltration and ground water flow

EVAPORATION- heat energy changes a liquid into a gas

CONDENSATION- air only holds so much water vapour before it becomes saturated. As the air cools, it turns back into a liquid

Oceans are a store, however sea water is salty. Meaning people can not use it unless its converted into fresh water. This process is hugely expensive.

Most of our fresh water is in ice sheets and glaciers, which are being reduced due to global warming. Relatively small amounts of water are stored in rocks as ground water, and in lake and rivers which are in high demand

-puddles from high rainfall find their way underground, inwhich they stay there for many years. If rainfall increases and goes on for a long time small stores fill up and flooding occurs

-caused by evaportation from rivers and oceans and evapotranspirtation ( evaporation and transporation- movement of water through a plant and then its loss into the atmosphere as water vapour) from trees which condense and cause precipitation

ROUTES OF PRECEPITATION

-some runs off surface

-some goes into rocks and soil

-some collects as snow or ice

-trees intercept precepitation, half of it is transpired and evaporated before it reaches the ground, this is known as green water

- if its a storm precepitation drips off leaves and stems and makes its way into the river system.

-it infiltrates soil and flows down hill through through-flow or if rock is permable it is stored here as ground water.

INFILTRATION- movement of water into soil

PERCOLATION-movement of water into underlaying rocks

-warm temps mean precipitation is more likely to fall as rain and not snow.

-more water vapour in atmosphere, will increase precipitation

-more intense storms due too an increause in precipitation intensity, which means more rain will fall in a shorter amount of time

-as the atmosphere gets warmer precipitation will increase, with warmer temps evaporation could increase from soils-which make drought more likely

 IMPACTS OF RIVER FLOW

-warmer climate= Early arrival of spring, meaning mountains could melt quicker increasing river flow in spring and reducing river flow in summer. This could affect amount of fresh water avalible in the summer, when water is at its highest demand.

-semi arid land in sahara desert

-rain falls only 1-2 months a year

IMPACTS OF THE DROUGHT

-grass dies meaning animals can not graze

-over grazing causes soil erosion and desertification

-rivers and water holes have dried up

IMPACT ON PEOPLE

-more water born diseases such as chlorea

-women and children do not work or go to school as too busy having to collect water

-high risk crop failure and animal death

-businesses and schools require water, so therefore can not open

-people have less money as having to spend it on fresh and clean water

DEVELOPED

--water prices will rise as money will be needed to spend on pipes and resovoirs

Developing

-more vunrable to drought and crop failure as rely on rain fall

INDUSTRIAL POLLUTION e.g china and india

-chemicals from manufacture of pesticides can poision a river and kill forms of life

-radio active substances can cause cancers

-thermal pollution stop water from being able to retain oxygen

HOWEVER- as a country develops, so does its polltuion laws

 INTENSIVE AGRICULTURE

-fertilisers run off into rivers, which cause eutrophiation, which lead to rapid growth of algae

-animal manure also causes eutrophication which kills many organisms

SEWAGE

-e,g mumbai which has many shanty towns do not have any sewage systems. So the place where sewage is dumped is also where they get their water from for cooking and cleaning and swimming which cause

-chlorea

-kills fish

-consumes the waters oxgygen and kills organisms

OVERABSTRACTION

e.g thames valley river

-drops river flow and then leads to drought

-this increases use of ground water supplies

however CAMS are designed too manage local water supplies

RESOVIOR BUILDING

-loss of land by drowing houses and farm land

-disease e.g mosquitos

-cause flooding

DEFORESTATION

-removes the trees of evapotranspiration

-exposing soil surface to intense heat and hardens the ground mkaing it impermable and increases run off

-loss of soil nutrients

-lead to flooding as trees intercept

-$49 million

-created lake mead which is a resovoir supplying water to 8 million people in las vegas and canada which are very arid

PROBLEMS

-all of the coloradas river has been used to none reach the sea

-birds and fish species have declined

-lake mead is nearly all used up

SOUTH TO NORTH WATER DIVERSION

- transer water to the drier norht

-complete in 2020

- cost around 50 million

PROBLEMS

-loss of ancient sites

- displacement of people

-more water pollution

THREE GORGES

--26 million

-designed to reduce flooding

-produced 80 billion kwh of electricity a year

- provides farms water in dry seasons

PROBLEMS

-1350 villagers and 150 towns relocated

-water quality is low due to sewage and farm waste

NGOS SET UP IN DHAKA BANGLADESH

-six deep tube wells which save people time collecting water and two new sanitation blocks providing toilets and water

ADV

-people are no longer ill and run the projets themselves and helped them move out of poverty

BEFORE- they had no safe water or clean toilets