Monday, 28 March 2011

Holderness Coastline

Dear Lower Sixth!

Welcome to an online post especially for you to help you with your work whilst we are in Iceland. You will be starting your first major case study of this module, the focus is on coastal erosion and management, and the area is Holderness in East Yorkshire. This is one of the most rapidly eroding coastlines in the UK, and can retreat as fast as 2m a year. The stretch of coastline you will be studying runs from Flamborough Head in the North, to Spurn Point i the South, the sediment underlying much of Yorkshire is Glacial till, and there are high grounds to the West which mark the western limit of Ice sheets during the last ice age.

So, what is coastal erosion? Let the Environment Agency explain!
Rock type is important, Till is a very immature rock, it forms under ice sheets and in Yorkshire is as young as 50 000 years old. The rock is soft, unconsolidated and composed of mud's and some sands with pebbles in it:
As such, the rock is very easy to erode, particularly over the winter when wave strength is at its highest, as seen in this short clip of the waves over winter breaking against the soft till:

There are some good intro videos to the case study already made for us, so here's a good basic one:

This is an excellent clip showing a time lapse photo project over a year in Yorkshire showing how much erosion and deposition takes place:

Why is this such a problem for Holderness? Well, you will get plenty from the video notes, including a rather interesting lady who loses her cows over the edge of the cliff. But Holderness is a real tourist honeypot site, there are numerous holiday parks and mobile home sites right on the coast, unfortunately they are at serious risk and many have already been lost to the sea:

There are of course defences in place, but many are now ageing and in need of replacement, such as these groynes at Hornsea which are not overly attractive to tourists wishing to use the beach:
Yet, groynes are a relatively simple form of defence and the tourists would rather have a beach with groynes than none! They do however cause Terminal Groyne Syndrome, a rather painful affliction if you are a beach, which sees the sand piling up in some areas, and therefore being depleted in others (remember sediment cells are systems). The worst example of this is Mappleton, and it has resulted in certain areas of the coastline being protected through an aggressive Hold the line strategy, and some being lost through managed retreat with the creation of the five new bays. 

The decision has been taken to defend Mappleton at the expense of the down drift towns such as Cowden (The former location of the Earle Farm which has now largely fallen into the sea).
This clip is part of the Blue Peter from 1994 that focused on Mrs Earle loosing her farm to the sea, much of this farm has now gone, as a result of the protection installed at Mappleton to protect the road and the village. This is an excellent example of a cost-benefit analysis, it cost less to build two groynes at £1 million each in Mappleton, than to relocate the road and the residents, but the Earle farm paid the price in 1997. To add to their misery, they were then asked to pay for the demolition costs at their farm as the building was slowly falling into the sea. Quite often, insurance companies do not pay for claims as a result of what is known as a "gradually operated cause", as in coastal erosion, so for many of these homes at risk from receding coastlines, there is no compensation.
This is an excerpt from a geography revision forum on the topic:
  • Coastal erosion - Holderness coast, Yorkshire.
    Tip: Remember the shape of the coastline as the man with a beard
    • Main rock is boulder clay so cliffs are unstable. Other main rock is chalk
    • Cliffs retreat by 2m a year
    • 50 villages that exist during the medieval times are lost today
    • 5 km of land already lost
    • Major features (in order from north to south) – Flamborough Head, Holderness Coast and Spurn Head
  • The Great Debate – Protect Mappleton/ B 1242?
    • Problem: Protecting an area of land always mean greater pressure and coastal erosion on neighbouring stretches of coast
Hornsea is a big town so groynes are necessary. However this means greater coastal erosion will occur in the south; meaning it would affect Mappleton. Mappleton is a small village but an important road, the B1242, runs through it and losing it would mean compensation of millions of pounds. Planners decided to protect it, but this would mean the coastal area down further south will suffer from greater erosion (10 metres a year).
FOR Build rock groyne - trap sand at Mappleton - southern coast and farms destroyed
  • One example would be Sue Earl, a farmer in Great Cowden. Although she had lost a lot of land every year, she was determined to keep the farm running. Eventually the sea will claim the whole farm so she had to give up, especially when the farmhouse went too.
AGAINST Do nothing - Mappleton and parts of B 1242 destroyed; huge compensation - sands continue protect southern coast and farms

A new development is that permission has been given for a huge offshore wind farm just offshore from Spurn

Your comparative case study will be Lyme Regis, which we will cover on the trip, but in order to prepare yourself here is a video explaining why Lyme is an important site, not only for the town itself, but also for the South West:


Work to do this week:

  1. Watch the video on Holderness and Spurn Head
  2. Read the module booklet pages 48 to 54
  3. Complete the side of the sheet with the map on it.
  4. On the reverse, make bullet point notes on considerations for coastal management split into the four categories (Social, Economic, Political, Environmental) we will add to these when I return.
  5. Answer the past paper questions on pages 55 and 56 for me to take in next Tuesday
 I know we have not yet covered sand dunes and salt marshes, but you need an introduction to management before the field trip to Lyme Regis next week, on that note, please sign up asap, the Thursday and Friday sessions are filling up, and the trip is an important part of your course.

Any questions please have a word with Richard!

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