LOWER SIXTH - CJ SCHEDULE, WEEKS 2-9
MODULE 1 THE DYNAMICS OF CHANGE
10.1 Physical Geography: Shorter Term and Local Change
SPECIFICATION CONTENT
DETAILED CONTENT/LESSON FOCUS
SKILLS
Atmospheric, geomorphological and human processes affecting drainage basin hydrology.
CJ SCHEDULE
WEEKS 2-9
Weather changes associated with the passage of a depression. General characteristics of a mature depression: Low pressure/rising air Warm and cold air masses/sectors Fronts/cloud types/rain Wind speed and direction Scale and speed of movement Measurement of physical characteristics in a physical environment.
Primary source collection.
ICT. CDRoM, Internet.
Reading weather maps: symbols, isobars, etc..
Anticyclonic weather conditions in winter and summer. General characteristics of an anticyclone:
High pressure /sinking air
Character depends on the airmass (cP, mT, cT air)
Wind speed and direction
Scale and speed of movement Summer: drought, heatwave. Winter: low temperature, " anticyclonic gloom", snow on the East coast.

Weather revision
Measurement of physical characteristics in a physical environment.
Primary source collection.
ICT. CDRoM, Internet.
Reading weather maps: symbols, isobars, etc..
Features of a drainage basin system:
The Drainage Basin Model  
Base flow
Interception
Infiltration
Throughflow
Run off
Definitions of each feature of the drainage basin model.
Interrelationships within the drainage basin model:
Inputs and outputs; stores and flows.
Measurement of physical characteristics in a physical environment. Briefing
Primary source collection.
Infiltration rates
- Data
  Variation within drainage basins:
Soil and rock type
Vegetation cover/type
Seasonal change
Intensity of rainfall/ precipitation type (link to depressions etc..)
Antecedent precipitation
Drainage basins revision
 
The storm hydrograph Concept of Discharge
Character of the storm hydrograph: flashy/subdued.
Terminology, e.g. rising and falling limbs, peak discharge, lag time.
Hydrological cycle revision
Use of published statistical data: drainage basin data Presentation of evidence: the storm hydrograph as a composite line and bar graph.
The effects of human activity on the storm hydrograph. Effects to include both:
Urban: tarmac, buildings, storm drains resulting in a "flashy" response
Rural; farming, river management (dams), deforestation/ afforestation resulting in a varied response.
Use of published statistical data: drainage basin data Presentation of evidence: the storm hydrograph as a composite line and bar graph.
Geomorphological variations within drainage basins:  
Erosion, Transport and Deposition and how they are related to Discharge Types of erosion- Abrasion, Hydraulic Action, Solution (Corrosion), Attrition
Methods of Transport/ concept of load (capacity and competence) suspended, dissolved, bed load

Deposition occurs due to decrease in velocity and /or discharge or increase in loads
Primary source collection:
Fieldwork. The measurement of physical characteristics in a physical environment. Morphological mapping
Sketch maps
Field sketch/ annotation
How they are related to Discharge How these are related as shown by the Hjulstrom Curve and its interpretation. Secondary source utilisation:
Published data of channel morphology
O.S. maps in a variety of scales
photographs and their interpretation, satellite imagery
Long and cross sections of river valleys
Channel Morphology Measurement of channel shape: wetted perimeter; hydraulic radius, change in the width depth ratio and how this affects the efficiency of the channel. Variation with discharge ( e.g. floods)
Contrast between straight symmetrical channels and asymmetrical meandering channels with links to velocity erosion and deposition.
 
Variations in the valley long profile and the valley cross profiles of a river Gradient changes in a valley long profile ( waterfalls, lakes, rapids, rejuvenation: link to changes in velocity and discharge.
Upper, Middle and Lower course landforms. Development of the flood plane and its features, e.g. oxbow lakes, levees.
Long and cross sections of river valleys
Sketch Maps
Field Sketches and annotations

Rivers
1999
1(a)What is meant by each of the following terms:
(i) river abrasion? (ii) hydraulic action? (4)
(b)Choose ONE feature produced mainly by river erosion. Cescribe its characteristics, and explain the processes which have led to its formation. (6)

(c)describe two ways in which people have modified river channels in none urban areas. (5)

1996
2You have heard that it is intended to build a large new housing estate on rough grazing land on rhe edge of an urban area. A stream flows through this rough grazing land towards the urban area.
(a)Briefly describe one technique you could use to measure the discharge of the stream before the development took place. (5)
(b)Suggest, with reasons, how the discharge may change once the building programme is complete. (10)
(c)Indicate problems which the new discharge may cause for local people and suggest how careful planning could reduce such problems. (10) (15)

1998 '.Study figures 1,2 and 3 which show the passage of a depression over the British Isles on the 25th January 1990.
(a)Prepare a summary of the weather on 25th January in London for a late night news programme.
You should describe the changes in the weather that have occurred, and also the links these changes to the passage of the depression. (9)
(b)Flooding usually results from a combination of factors such as slope, human activity, soil properties and storms.

With reference to non urban areas in the British Isles that you have studied, show how these factors may combine to produce flooding. (6)
(c)Describe one attempt made by people to reduce the occurrence of flooding.(5) (20)