Geography

Water GQ2-GQ4

How does the hydrological cycle ensure a continuous supply of water using schematic diagram?

The hydrological cycle describes the continuous movement of water and a sequence of processes such as evaporation and condensation which allows water to be continuously recycled between the earth’s surface to the atmosphere and back again.

Explain water budget using schematic diagram

1. water deficit ( input is less than output)

2. water surplus ( input is more than output)

3. water balance ( input = ouput

Examples of how water are used by people

Domestic, Agriculture, Recreational, Industries

Describe how water is used in industries

1. Cool equipment in factories and power plants as they generate a lot of heat

2. Generate hydroelectricity when water passes through turbines installed dams

3. Cleaning agent in water fabrication which is the process of creating electrical components found in computers and mobile phones

Describe how pollution is caused by human actions

1. Farmers using excessive fertiliser

Excessive fertiliser from farms get washed into the river by rain. The excessive fertiliser provides additional nutrients for algae to grow rapidly. When the algae dies, they are decomposed by bacteria which takes in oxygen during the process. Thus there will be less oxygen in the water, causing other aquatic animals to die.

2. Factories releasing toxic chemicals into the river

The water becomes unsuitable for aquatic life resulting in the death of many aquatic animals. The water also becomes unusable for people living near the water thus they may need to spend a large proportion of their time searching for clean water.

What are the health risk that people may have if they come into contact with contaminated water?

if people come into contact with contaminated water especially with open cuts or wounds, they may suffer from infections. If they drink the contaminated water, they may suffer from water borne diseases such as chlorea.

Strategies taken to sustainabily manage water rationed

1. Using laws

Advantages: Laws create a legal framework that holds industries accountable. Laws can help promote long term environmental protections

Disadvantage: Enforcing laws constantly can be difficult especially in big countries. Require significant financial prospects which may be a burden for less developed regions.

2. Campaigns

Advantages: Encourage community involvement. Promote long term behavioural change

Disadvantages: Behavioural changes may take time and may not lead to immediate reductions. Relies heavily on voluntary compliance

3. Improve water technology

—> Water from local catchment

—> Imported water

—> NEWater

—> Desalinated water

Explain the advantages and disadvantages of desalinated water

Advantages: Not dependent on rain fall and can be used to supplement water supply during a long dry spell.

Singapore is an island surrounded by a limitless supply of seawater, thus it will never run out of water to desalinate

Disadvanteges: Very expensive to produce as production is energy intensive

Large amount of chemical and salt solutions are produced during the desalination process and may cause pollution if they are not disposed properly

Explain the advantages and disadvantages of NEWater

Advantages:

Not dependent on rainfall as it is produced from used water

Ultra pure and high quality

Disadvantages:

Expensive to produce as it uses membrane technology which is expensive and energy intensive

Public may find difficult to accept this new technology of obtaining water from used water due to lack of knowledge of treatment process

Explain the advantages and disadvantages a imported water

Advantages: Does not require land, frees up land for other uses

Cheaper source of water compared to desalinated water or NEWater

Disadvantages: Importing water may not be enough to meet water demands especially during a long dry spell

Water agreements will expire eventually and there are no guarantees of future agreements.