THE place to go for Sea Level Change information is the website of MIDDLESEX UNIVERSITY's SURVAS PROJECT. It has some excellent powerpoint slides and images. It also has links to sites which have some academic rigour. It will take a little exploration to unearth the important information, and you should always be certain to credit ANY SOURCES that you use.
Information below is adapted from SURVAS website. Please credit them if using and pay a visit for more.
It is estimated that 21% of the world's population already live within 30 km of a shoreline. Coastal populations are also growing more rapidly than global mean trends, including urbanisation and the development of many large coastal cities. At the same time, global sea levels are rising and this rise is expected to accelerate significantly during this Century due to anthropogenic global warming. These adverse trends raise questions about the possible impacts and human responses to the likely changes from the sub-national to the global scale.
The terminology used is ASLR: Accelerated Sea level rise. A little like the use of the 'enhanced' Greenhouse effect. This would be a useful thing to mention in any exam answers on this issue.
Primary impacts of ASLR
Even small increases in sea-level rise could cause major primary impacts on the
world's coastal zones in terms of:
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Secondary impacts of ASLR Threats to food production capacity including decline in irrigation water quality, decline in coastal crop yields, and degradation/disappearance of crucial ecosystems such as mangroves, corral reefs and coastal lagoons which act world-wide as fish and shell fish nurseries. · Decline in health/living standards as a result
of decline in drinking water quality, threat to housing quality,
associated increasing health hazards linked to relocation, and
spreading of disease vectors.
Possible displacement of vulnerable
populations
Relocation of impacted populations and associated political, economical, institutional, and cultural stress of both the displaced population and the host countries.
Impacts on infrastructure and economic
activity
Decline in land and housing property values Threats to major infrastructure (including strategic harbours, coastal roads, railways, health and school buildings) Threats to major coastal industry and services (including oil/petrochemical plants and tourism) Diversion of resources to adaptation responses to sea-level rise impacts Increasing protection costs which may not be affordable to certain developing countries unless substantial aid is obtained. Increasing insurance premiums Political and institutional instability, and social unrest Threats to particular cultures and ways of life (e.g. in specific environments such as atolls where retreat to higher inland areas is not feasible |
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Other impacts of climate
change a decline in sea ice, possible changes in frequency and intensity of coastal storms, more intense precipitation events. |
The Irish ENFO site has some useful resources on this, and lots of other environmental issues.
The ENVIRONMENT AGENCY will obviously have to deal with the impacts:
http://www.environment-agency.gov.uk/yourenv/432430/432434/432475/438776/?version=1&lang=_e
An ISOSTASY page with animations is here.
http://www.bbc.co.uk/climate/ - BBC CLIMATE CHANGE site
There are details of some features caused by sea level change in the GA 'Classic Landforms of Skye' book. This has some details on the raised beaches at Braes, where a friend of mine used to live, and close to the home of the late Sorley Maclean. This is a great place for a walk, with views to Ben Tianavaig and across the Narrows to the Isle of Raasay.
A useful article here on the PROBABILITY OF SEA LEVEL RISE. from the US Environmental Protection Agency (EPA)
http://yosemite.epa.gov/oar/globalwarming.nsf/content/ResourceCenterPublicationsProbability.html
http://www.telegraph.co.uk/news/main.jhtml?xml=/news/2006/12/27/nlondon27.xml - an excellent article and map about London-On-Sea. New for 2007...
Some excellent PDF format notes at the Birkbeck College site give some of the economic background to sea level change, be it EUSTATIC or ISOSTATIC. They include some useful economic statistics for use in the human impact of these changes.
Approximately 10% of England's population is potentially at risk from flooding or coastal erosion - the at risk area extends over 1 million hectares and includes property worth £200 billion and farmland worth £7 billion. Of this, at least half is in the Thames region. Investment in sea defences is less than is required, and a failure to invest in defences will lead to continued (and increased) losses.
Remember that you need to have NAMED and LOCATED examples of landscapes of REGRESSION and TRANSGRESSION.
TRANSGRESSION is when the land is flooded by a relative rise in sea level e.g. RIAS, FJORDS, FJARDS - make sure that you can name examples of these.
Coming soon: SEA LEVEL POWERPOINT and FJORD IMAGES
REGRESSION is where land is 'uplifted' or the sea level drops relative to the land. This produces RAISED features. A useful site on this theme is the work of Pete Robinson (Updated June 2006). He has produced an excellent illustrated guide to the BALNAGASK HEADLAND, which is situated just to the south of Aberdeen Bay. There are images of the RAISED CLIFFS, KAMES, photos of key ROCK TYPES and other coastal and glacial sedimentation features. Nice work Pete !
Students should be aware of the significance of the FLANDRIAN TRANSGRESSION. The Flandrian is a period of time when sea levels have risen relative to the land, and therefore covered areas which were once above water. REGRESSION is when coastline recedes to reveal land, and appears to raise landforms above the present sea level. These become RELICT features, such as at Dougarie and Lochranza on the Isle of Arran, and the Isle of Jura, where there are raised beaches over 40m above sea level (as featured on the Natural History of the UK with the noted geographer Alan Titchmarsh)
With the aid of the information on this page, other websites and textbooks (which were around before all this Internet business started remember...) answer the following 3 questions:
a) What are the causes of the changes in sea level that have affected the British Isles (and in particular the rise in sea level over the last 10,000 years) (6 marks)
b) Identify what effects the rising sea levels can have on human and economic activity on coastlines (6 marks)
c) Write an extended paragraph (and include maps and diagrams if helpful) to answer the question below:
With reference to an example from the British Isles, explain the effect that changes in sea level have had on the landforms and activities on that stretch of coastline (8 marks)
The final question should cover both rising and falling sea levels relative to the land. Clear use should be made of the terminology: Eustatic, Isostatic, Regression, Transgression
TOTAL: 20 marks
It's also worth noting that not everyone is convinced that any of this is happening... Keep an eye out for some sites which may not be all that they seem.
Check out http://flood.firetree.net/ for some interactive maps which allow you to see the effect of raising sea level on your own home area, or other parts of the world. Some interesting effects on King's Lynn - easy and effective. Recommended...
This allows you to look at the effects on your own house if you live near the coast - as I do.
I'm OK up to about 9m increase.
New addition for 2007 is a resource for Google Earth / Worldwind, produced by Noel Jenkins.
Check it out at: http://www.juicygeography.co.uk/sealevel
