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    This report is a contribution to the Strategic Environmental Assessment (SEA6) conducted by the Department of Trade and Industry (now Department of Energy and Climate Change). This report reviews the many different sources of underwater noise, both natural and anthropogenic, that combine to provide the background noise levels in which marine organisms need to survive throughout the SEA6 region. The sources of sound combine together in a complex manner resulting in significant spatial and temporal variations in the noise field. A map of the dominant noise sources in the Irish Sea is shown, indicating that man-made noise is the dominant source of noise over about 70% of the area. Shipping noise is likely to be dominant across large parts of the SEA6 area. To fully characterise the ambient noise field in the SEA6 area would require multiple measurements at a large number of locations over a period of a year. However, a considerably lower cost approach would be to characterise each sound source and to use this with occurrence statistics for each source to model the ambient noise field across the region. The advantages and disadvantages of the acoustic modelling approach are discussed.

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    This report is a contribution to the Strategic Environmental Assessment (SEA7) conducted by the Department of Trade and Industry (now Department of Energy and Climate Change).The class Cephalopoda comprises three major divisions, of which two: Decapoda (squids and cuttlefish) and Octopoda (octopods) are represented in the SEA 7 Area. They are highly developed, but short-lived molluscs with rapid growth rates. They are important elements in marine food webs and interact significantly with marine mammals, seabirds and commercially exploited finfish species. They also represent a promising future fishery resource in terms of market value, abundance and growth potential. At present, only an estimated 10% of exploitable stocks are utilised worldwide. There are six marketable squid species that occur in the SEA 7 Area. These belong to the long-fin (loliginid) and short-fin (Ommastrephid) squids the two most important exploited families of decpods. In the SEA 7 Area, only one species, Loligo forbesi is commercially exploited on a regular basis, although there are significant landings of other species on occasion. The closely related Loligo vulgaris sometimes appears in catches and the small Alloteuthis subulata is thought to be naturally abundant and an important food item in the marine ecosystem. There are other important species represented in the SEA 7 Area. These include cuttlefish, octopods, sepiolids and a number of deep-water species. Most of these are marketable and may be ecologically important. Large fisheries for some of these species, particularly octopods and cuttlefish operate in European waters further south, but they are not currently exploited in the SEA 7 Area.

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    This report is a contribution to the Strategic Environmental Assessment (SEA7) conducted by the Department of Trade and Industry (now Department of Energy and Climate Change). The report concentrates on reviewing existing data and published sources, rather than attempt a quantitative baseline of wrecks and casualties. There is a comprehensive corpus of legislation, plans and polices concerned with the protection of the submerged maritime archaeological resource within the SEA 7 study area. The study outlines the known history of maritime activity within the SEA 7 area. Despite being an extremely large body of water that at times can produce dangerous sea and weather conditions, and encompasses the rugged coastlines of western Scotland and Northern Ireland, the area has been used extensively by seafarers from at least the Mesolithic (from 9000 BC) up to present times. During each time period there has been evidence of human activity within the SEA 7 area, often demonstrated by the discovery of maritime archaeological remains. The waters between the north east of Ireland and Scotland have been used as a means of communication throughout the centuries. Previous investigations of maritime archaeological remains within the SEA 7 area are discussed in the report. The spatial distribution of submerged archaeological remains is discussed, and comments are made on the limitations of any mapped baseline of data. The study concludes with a comment on the potential impacts of oil and gas activities on the submerged maritime archaeological resource and suggests possible monitoring methodologies.

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    This report on underwater noise is a contribution to the Strategic Environmental Assessment (SEA7) conducted by the Department of Trade and Industry (now Department of Energy and Climate Change). This report initially gives a general introduction to underwater ambient noise and the underlying mechanisms that generate sound. The report then identifies a number of sources of underwater acoustic noise, describes the characteristics of the noise including frequency content, levels and variability, and also identifies the current state of knowledge on each source. In all cases the sources are considered in the context of the SEA 7 area. Mechanisms that can modify the ambient sound levels are described. The dominant noise sources in the SEA 7 area are identified. Recommendations are then made for the methodology to be used to obtain meaningful characterisation of noise levels in order to establish baseline levels. The report then goes on to present an analysis of measured ambient noise data in the SEA 7 area, model predictions of spectrum levels, and compares the measured and modelled data.

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    A seabird and cetacean survey was conducted onboard RV Kommandor Jack in July 2002 as part of the Department of Trade and Industry's (now Department of Energy and Climate Change) Strategic Environmental Assessment (SEA4) of the Faroe Shetland Channel.

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    As part of the UK Department of Trade and Industry's (now Department of Energy and Climate Change) ongoing sectorial Strategic Environmental Assessment a seabed survey programme (SEA5) was undertaken between August and early October 2003 for the UKCS areas lying between Scotland and Orkney and Shetland. This report summarises the sediment total hydrocarbon and aromatic data generated from the analyses of selected samples from the study areas detailed: Fair Isle - 46 to 198m water depth; Outer Moray Firth A - 61 to 171m; Outer Moray Firth B - 57 to 100m; Sandy Riddle - 30 to 70m; Smith Bank - 39m; Southern Trench - 76 to 252m.

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    This report is a contribution to the Strategic Environmental Assessment (SEA7) conducted by the Department of Trade and Industry (now Department of Energy and Climate Change). Occurrence of carbonate and other mounds in the SEA7 region of the Atlantic Margin. This report focuses on the distribution, classification and internal (seismic) structure of carbonate mounds to the west of Ireland and the UK within the SEA7 region and its general environs. It also provides an overview of the main results from ongoing research in EU 5th Framework projects such as GEOMOUND, ECOMOUND and ACES. Various models for the origin and growth of carbonate mounds have been proposed in the literature. These range from hydrocarbon seepage and nutrient models to oceanographic and current influences and are discussed. The report also provides a comprehensive bibliography of mound references, a map of mound locations and a compendium of relevant metadata from the region.

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    As part of as part of the Department of Trade and Industry's (now Department of Energy and Climate Change) Strategic Environmental Assessment (SEA2) a geophysical survey was carried out in three different quarters of the North Sea: Norfolk Coast (Area 1), Dogger Bank (Area 2) and Fladen Ground (Area 3) from Kommandor Jack SEA2 Survey Leg 1, 2001. Multibeam, sidescan sonar and chirp seismic data were collected. The survey was carried to identify potential offshore Special Areas of Conservation (SACs). It was necessary to acquire data on specific features identified in the EU Habitats Directive, such as sandbanks and pockmarks, some of which might subsequently be defined as SACs. The survey was carried out in two legs. Leg one included the geophysical surveys in three different quarters of the North Sea as well as the charting which was used to guide the sampling and photographic work on the second leg. The following data are available - 25 files of processed multibeam data. Screenshots of backscatter processing are also available. Side-scan mosaics. Images are available from 15 boxes. Processed seismic data. Cruise report

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    This report on archaeology is a contribution to the Strategic Environmental Assessment (SEA7) conducted by the Department of Trade and Industry (now Department of Energy and Climate Change). There is a high likelihood of surviving prehistoric archaeology (10,000 - 5000 years old) in certain areas of SEA7, most notably to the west of the Outer Hebrides for a distance of some 10km, to a depth of -20m, and in and among the islands elsewhere (particularly around Islay, Jura, Mull and the Small Isles) along the coast and between S Scotland and N Ireland. The reasons comprise a complex interplay of changing sea level and the rebound of the land once freed from the compression of ice at the end of the last Ice Age. The net result of these physical effects is that 10,000 years ago relative sea level has been up to 45m lower along much of the coast and this corresponds with the period of early human settlement in the area. In places this means that considerable areas of submerged land exist. An investigation of bathymetric, sedimentary and tidal data for the area suggests that the prehistoric land surface, including archaeological remains, may survive in many places. Cooperation between existing extraction companies and renewable industries and archaeologists elsewhere in Britain shows how the recording and investigation of archaeological material could be beneficial to both parties should work take place in SEA7. The final sections provide a preliminary examination of how matters might be taken forward to safeguard the archaeological knowledgebase without prejudicing commercial interests.

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    This report is a contribution to the Strategic Environmental Assessment (SEA3) conducted by the Department of Trade and Industry (now Department of Energy and Climate Change). The report documents the known and likely occurrence of prehistoric archaeological remains across the whole floor of the North Sea including the SEA3 area, and makes suggestions on how to enhance the finding and reporting of such artefacts. Sea level change associated with the retreat of the last glaciation led to almost the whole floor of the North Sea being dry land at some time or another in the past 20,000 years. Similar exposure of the North Sea floor was also associated with earlier glacial cycles. Thus prehistoric submarine archaeological artefacts can occur over a wide area of the North Sea floor, as far north as the latitude of the Shetland Islands. While artefacts dating from the last 12,000 years are most likely, human or proto-human artefacts as old as half a million years may have survived in places. Submarine archaeological studies in the Danish Archipelago have established that coastal sites were an optimal place for prehistoric human occupation. Similar coastal sites existed over many parts of the North Sea floor in the past. The potential impact of oil and gas operations on submarine archaeological remains is discussed. Pipe entrenching is the most likely process to uncover prehistoric archaeological deposits.