Hydrosphere

In this section you will revise:

  1. The movement of water through the hydrological cycle and drainage basins.
  2. Map work for rivers and valleys.
  3. Causes of flooding and flood map work.
  4. Hydrographs

The Hydrological Cycle

Watch this video, it will tell you about the hydrological cycle. This is an unusual question and is quite imple to answer. When you are answering this question you must refer to all of these terms in detail. This means you must give some description of what each term means.

Model answer:

The hydrological cycle is powered by the sun. The sun's insolation heats the sea and causes water to be turned into vapor by process of evaporation. This vapor rises and is transported trhough the atmosphere by process of advection. It is here that the vapor condenses inot water droplets which become too heavy and fall as precipitation. The precipitation sinks through soil as infiltration, eventually turning to through flow once bed rock is reached. Water moving over the soil, or surface run-off moves over the ground as rivers or streams. Vegetation soaks up some water and this is returned to the cycle via evapo-transpiration.

The Drainage Basin

Drainage basins are the area that is drained by a river.You may be asked to describe the movement of water through a drainage basin. This is a relatively common question and should not pose any difficulty to you. Follow the tabel structure given, turning each stage into a sentence or two should get you the marks you need. Again, try to talk about each stage in some detail, showing that you uderstand the meanings of the terms you are using.

Inputs Stores Transfers Outputs
Snow melt Lakes Surface run-off Discharge to ocean
Precipitation Channel storage Infiltration Evaporation
  Snow and ice Through flow  
    Stem flow  

Recognising River and Valley Features on a Map

In this kind of question it is useful to revise the following table. The two columns contain the features of rivers and valleys that you can always find; these marks are therefore garuanteed to be available to you if you can find them. There are of course many other features you can identify as demonstrated in the clip.

River Valley
Direction of flow Compare width
Tributary Compare steepness of sides
Confluence point Shape of valley
Width of river Change in gradient

 

Reasons for Flooding

You can be asked how changes made to the landscape by people can increase or decrease the chances of flooding. Check your notes for the best quality of detail but this clip should give you an idea of the kind of things you can talk about.

Hydrographs

Often regarded as a 'tricky' question these are actually fairly straight forward as long as you revise a good range of reasons why rivers flood at different speeds. Your notes contain many reasons (over 20!) so I would advise choosing 10 that you are most happy with and using those. Make sure you have a balance of comments relevant to different times of year and to rural and urban environments as the hydrograph will normally specify a date and location

Feature of River Landscapes

Listen to this RevisionBlast for a quick lecture on how the main features of river landscapes are formed.

Waterfall Formation

Waterfall formation is a common question that relies upon good use of clear diagrams and proper reference to appropriate processes such as abrasion and hydraulic action.

Meander Formation

Meander formation is a challenging question. You must make sure to refer to the processes mentioned in diagram one and after that it's fairly straight forward. Practising your diagrams for this kind of question is good reivsion.

Ox-bow Lake Formation

Ox-bow lakes are a logical continuation of your studies in meander formation. Make sure you have the two answers clearly separated in your head before going into the exam.