physical fieldwork

what is your physical fieldwork

Sea defences at Walton on the Naze effective at reducing erosion

what are the hard engineering sea defences at Walton and how do they help

• Sea wall

• Groynes : absorb energy , traps sediment

• Rock armour : absurd energy from swash

what are soft engineering sea defences at Walton

• vegetation : intercepts

How did you collect data (beach profile)

• beach profile

  • lay tape measure from sea to sea wall

  • at every 4 metres Dif hole in sand till you find clay

  • measure depth of hole

  • repeat this till sea wall

  • to measure angle use two ranging poles and place then at 0 + 4m

  • use clinometer and line up where red and white lines meet up

How do you collect data (longshore drift)

• throw orange into sea and record distance it moves in two minutes

• one person should use trundle wheel to track orange

How did you collect data (pill box measurement)

• use tape measure or trundle wheel to measure distance from each pillbox to bottom of the cliff edge

• then calculate rate of erosion

what date did u collect from each data collection method

• beach profile

  • protected beach is 26cm deeper than unprotected

• pillbox measurements

  • average cliff retreat of 0.63m every year since 1940

• longshore drift

  • oranges move north

• cliff sketch

  • evidence of mass movement and weathering

why was Walton on the Naze suitable location for fieldwork

• experiencing significant coastal erosion

• range of soft and hard engineering sea defences

• has unprotected and protected so can compare

What were some risks of your fieldwork

• unstable cliff edge

• tide timing

• safety of students

How did you present Longshore drift data and that does the data show

• proportional arrow diagrams

  • shows longshore drift happens more along unprotected beach

  • shows Groynes work by interrupting led

How did you present Beach profile data and what did this data show

• cross section diagram of beach for unprotected and protected

  • protected is longer by 8m and deeper by 15.3cm

  • unprotected has a wave cut platform of 8m

  showing groynes are working

How did you present pillbox measurements data and what did the data show

• bar chart

  • without sea defences cliff would be eroding at 70 cm per year

Asses the effectiveness of your data presentation techniques

PROS

- clear visually, allows for comparison, units/ values on axes

CONS

- need appropriate scales for comparison, should locate on map to show distribution

Justify one type of data presentation method that could have been more appropriate

pill box chart - use an actual scale line so its more visual

pros, cons and improvements of beach profile in terms of data collection

pro: lots of data , use of systematic sampling (every 4m)

cons: human error

improvements: use a laser instead of trundle wheel to measure distance

pros cons and improvements of longshore drift in terms of data collection

pros: found an average, left for a set time of two minutes

cons: not accurate, not true reflection of lsd at Walton

improvements: use a tracer/ tracker on a pebble (same weight as sediment) and put it in sea for couple of months

pros, cons and improvements of beach sketches

pros: annotated, snapshot of scenery

cons: unclear

improvements :take photograph, have more time to draw/annotate

pros, cons and improvements of pillbox measurements in terms of data collection

pros: easy to collect, use of trundle wheel

cons: uneven surface of wave cut platform - distance isn’t accurate

improvements : use a laser to measure distance