2007 Listings

Press Release - Immediate 11/5/07 LowTide 2007 - Saturday May 19

Celebrate the UK coastline! People are gathering together on Saturday 19 May to join in a day of inter-tidal celebration called LowTide 2007.

LowTide is held every year on the Saturday in May with the lowest tide. Environmental groups around the UK share their unique beach environments on this special day. The public are invited to attend a free LowTide event in your area. There are over 20 sites around most of the UK coastline. Please see http://www.riverocean.org.uk/lowtide/lowtide2007-listings.htm for more details. Activities are for the whole family - come and experience the amazing world uncovered by the tides! Inter-tidal lands and estuaries contain a huge diversity of plants, birds and animals; they can also hold fascinating archaeological and geological clues to our past and our future.

Celebrating tidal lands around the UK on the same day and tide will raise awareness about our precious marine resources, and how we can co-operatively cope with managing fishing resources and a changing climate. There are two areas of coastal concern that events will be highlighting to the public: Sustainable Fishing and Sea Level Rise.

Sustainable Fishing: our fishing resources have never been under as much pressure as they are now. We are giving away 'Fish & Tips' guides which explain what are the top ten most consumed fish in the Uk and how the consumer can make sensible sustainable choices. More details can be found here.

Sea Level Rise: We are experiencing climate change much sooner that anticipated. The most recent IPPC 3rd report confirms sea level rise will have huge consequences for the planet. The UK is vulnerable to sea level rise at many locations around our shoreline. We provide more context for this statement below.

 

Notes to editors: LowTide is a collaborative project between The River Ocean Foundation, a Brighton based environmental charity, and a growing number of groups and individuals throughout the region, nationally, and internationally. Radio, press interviews are welcomed. Contact Clive Pepe 07721 046213 RiverOcean, 113 Queens Road, Brighton BN1 3XG 01273 234032

 

UK Sea Level Rise - an overview

 

Intertidal Nurseries

The intertidal environment can be composed of mudflats or sandflats, which are areas of the foreshore and seabed that are exposed to the air at low tide and submerged at high tide. Estuaries can form typical intertidal zones as they are partly enclosed bodies of water at the mouths of rivers, which are subject to the tide. They are therefore open to saline water from the sea and fresh water from the rivers. When the current flows are reduced, fine sediments are deposited forming extensive mudflats and sandflats. An intertidal environment can therefore create an important range of habitats for a large variety of fish species to take refuge as a nursery during juvenile development. However, this environment is threatened by global warming. Climate change is changing the face of the planet and in 100 years the devastating impacts caused by global warming will drastically affect our coastline. Rising sea levels occur through the thermal expansion of water and the melting of ice caps. Furthermore, the coastline around Britain becomes more vulnerable to erosion by the rise in sea level. In addition, an increase in flood risk and other potential changes in storm frequency and intensity are also factors of concern. The Intergovernmental Panel on Climate Change (IPCC) has predicted a global rise in sea level between 28 and 43cm by 2100 and new research by the Environment Agency shows that by the year 3000 sea levels will still be rising and could reach heights of 11.4m. This would mean that without action low-lying intertidal coastal areas of the UK will be lost. Regions of specific concern include:

East Anglia

Sea levels are expected to rise by 50 cm by the 2050s in East Anglia. This would have devastating impacts on low-lying areas of Suffolk. The intertidal zone in Suffolk is composed of relatively unconsolidated materials laid down during the Pleistocene and Holocene, which are vulnerable to loss through erosion. One particular effect caused by a rise in sea level is 'coastal squeeze'. This is devastating to the intertidal zone as the area becomes trapped between the sea wall and the rising sea causing submersion. The hard river walls on the Suffolk coast threaten the intertidal zone with this effect. Furthermore, the Wash Estuary and North Norfolk coast also have low lying intertidal zones that are home to a large variety of species that live in the mud and sandflats including shellfish, which use the area as a nursery. The Wash itself is the largest bay of its kind in the UK and contains the second largest area of intertidal sandflats. Rich in diversity it is home to internationally important species of birds, fish and the largest colony of common seals. It is a Site of Special Scientific Interest, a National Nature Reserve and a Ramsar Site. Subjected to an increased rise in sea level the area is vulnerable to erosion and therefore a loss of shoreline. This would have a devastating effect in the loss of intertidal nurseries and species richness.

Southern England

Southern England is predicted to suffer the greatest from a rise in sea level as by 2080 it is expected to reach heights of 86cm. The reason is due to post-glacial rebound. As land masses rise that were once depressed by the weight of large ice sheets, during the ice age. Areas such as Scotland are rising at higher levels than the rest of southern England. This has the impact of sea level rise being able to more readily effect this lower lying region. The Thames Estuary in the south of England is an example of a threatened freshwater and marine fishery. It plays a vital role in providing a nursery for juvenile fish species. Species of commercial importance found within the Thames include sea bass and Dover sole and it is now recognised as one of the most important estuaries in the UK for both of these species. The Thames Estuary provides juvenile fish with a rich feeding ground and refuge from more intensively commercially fished areas of the lower estuary and southern North Sea. Fish nurseries within the Thames helps to support North Sea fish stocks, as fish are allowed to develop and long term breeding success is improved. The area is threatened by sea level rise. Flooding of the intertidal zone would devastate the marine diversity adapted to the estuary and therefore North Sea commercial fishing stocks.

Recent increases in sea temperatures in intertidal areas on the southern coast have also seen an increase in the abundances of species more adapted to living in warmer waters. For example the purple acorn barnacle has drastically extended its home range. Moreover, cold-water species of plankton, fish and intertidal invertebrates have declined in numbers and are retreating northwards. Warm water species are now displacing the older inhabitants. As sea levels continue to rise, it is thought that many marine species won't be able to adapt to the changing sea levels and temperatures and will in turn will face local extinctions.

Wales

A new report by the National Trust has stated that 70% of coastline around Wales could be severely affected by coastal erosion and flooding in the next 100 years. Over 230km of Welsh coastline is in care of the National Trust. Sea level rise and climate change leading to more severe storm events is predicted to impact these areas. Areas of particular concern include low lying coastal intertidal areas. All of which may disappear. Sixty six National Trust coastal sites covering 1572 hectares are at risk of flooding and two sites are vulnerable to tidal and river flooding in the next century. The National Trust is calling for long-term planning and urgent action to be taken to address the impacts specific to these areas.

Lancashire

Formby on the Sefton coast is shaped by two major river estuaries; the Mersey and the Ribble. Formby Point is the meeting point between these two estuary regimes. Tidal streams converge offshore and an intertidal sand split at Taylor's Bank has developed. The sand dune system around Formby Point is now highly susceptible to erosion from rising sea levels, storms and flooding. The Formby sands have been eroding at three to four metres a year and in 2002 12-15 metres was lost from the front of the dunes. This level erosion will only continue with the rising sea level in the next 50 years. The Ribble Estuary is of international importance for wildfowl as well as other marine species and flooding and erosion could have major impacts on the ecosystems. Furthermore, Morcambe Bay is the largest continuous intertidal area in the UK. It includes large intertidal mudflats and sandflats and is a popular fishing area particularly for flat fish, basses, cod, whitbait and shellfish, using it as a haven. As it is a low lying area, it is particularly susceptible to flooding, therefore the forecasted rise in sea level also threatens this region of Lancashire.

Scotland

Solway Firth on the Scottish coast forms an intertidal mudflat, which is an important nursery for flat fish in particular. It is also home to other species of worms, molluscs and crustaceans, which are important foods for many birds and fish. A coastal saltmarsh forms the upper vegetated part of the intertidal mudflat. This area is home to many important plant species. It is thought that sea level could rise as high as 25cm on the Scottish coastline by 2050. If this were to happen, flooding would inundate this area of coastline, leading to erosion. The biodiversity of the intertidal area would dramatically decrease. Another area of the Scottish coastline under threat is the Forth Estuary. It is an important roost site for birds, and the intertidal zone also forms a nursery for millions of young fish and shellfish. Sea levels are predicted to rise in Forth by 5-25cm in the next 50 years. The impact of global warming also increases the risk of high intensity storms, which causes flooding and erosion. In the inner Forth Estuary much of the land is low lying and sea defences will be over-topped leading to a 'coastal squeeze'. This would cause a further increase in flooding and rates of erosion in the intertidal area. If this occurs then the whole of this coastal region will be lost.

Intertidal areas are of great importance to marine biodiversity and the fishing industry as they offer areas of protection that allow the development of juvenile fish. Furthermore, they are home to some of the UK's most important and spectacular wildlife, particularly the thousands of migrating birds such as knot and avocet, which travel hundreds of miles to over-winter in the estuaries. At least 62 Sites of Special Scientific Interest, located in low-lying coastal areas of England, are threatened by sea level rise. Among these are some of the largest wildlife areas in the UK. These habitats which are vital for coastal protection are at most at risk and loss of these habitats can decrease species survivorship and have a devastating impact commercial fishing success. A rise in sea level of up to one metre over the next hundred years will severely damage the intertidal zone and long term planning to address the impacts is needed if we are to protect our coastlines.

References
Carmarthen Bay and Estuaries Special Area of Conservation

UK Marine SACs Project the vulnerability of intertidal zones
Humber Management Scheme

Thamesweb The Thames Estuary Partnership

Wikipedia - what are intertidal zones?

English Heritage - Coastal zone assesment of Suffolk
Suffolk Coasts and Heaths

The Independent - climate change is already affecting UK marine life
Sefton Coast Partnership

Morecambe Bay Partnership
Scottish Executive - action plans for biodiversity
Scottish National Heritage - Forth esturary sea level rise risk assesment
BBC News a summary of the most recent IPPC predictions

The National Trust - Welsh coastline in big trouble

The Environment Agency - warning that time is running out

Friends of the Earth - a good briefing paper about climate change
Natural England - clam controversy in The Wash
New Scientist - ice sheets complicate sea level calculations
Wikipedia - a definition of post glacial rebound