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Increasing evidence indicates that ongoing and future climate change impacts, such as enhanced coastal erosion driven by intensified storms and sea-level rise, will be destructive or problematic for coastal archaeological heritage. Approaches to this problem range from broad-scale GIS-based vulnerability assessments to site-scale monitoring and survey. In all cases, the approach chosen should be based on the best-available data on the local historic environment and pattern of coastal change. Therefore, this paper will demonstrate how such data can be successively acquired and enhanced using an integrated approach that builds on and refines a previously conducted broadscale vulnerability assessment. This approach was adopted in the study region (Northern Ireland) owing to a lack of coherent and upto-date information on shoreline change. This approach incorporated the GIS-based Digital Shoreline Analysis System (DSAS) to quantify and analyze local shoreline change. DSAS is a software extension for ESRI ArcGIS which allows calculation of rate-of-change statistics using past shorelines identified from georeferenced historic maps and vertical aerial imagery. Additionally, a field survey was conducted to assess the condition of recorded sites, and identify unrecorded ones. Results revealed a more complex pattern of shoreline change in the study area (Magilligan Foreland, Lough Foyle) than previously anticipated, with zones of significant erosion interspersed with areas of stability or advance. Fifty-one new sites ranging from the prehistoric period to the Second World War were also identified. The new information was used to develop a priority classification based on site significance, condition and risk level which improved significantly on the uniform classification of the original broad-scale assessment. [ABSTRACT FROM AUTHOR]

We present early to Mid-Holocene paleo-geographic reconstructions for the Ramore Head area (Northern Ireland). This coastal area is characterized by Mesolithic occupation (c. 10-6 ka) and preserved early-Mid-Holocene peats both on- and offshore. This paper improves on previous reconstructions by employing a backstripping methodology, which removes accumulated recent deposits from identified buried paleo-landsurfaces instead of using modern topography as an analogue to the past landscape. Paleo-landsurfaces are identified offshore from seismic profiles supplemented by cores, and onshore through legacy borehole records. The paleo-landsurface can be traced offshore to depths of −2 to −19 m and is buried by <5 m of modern sediment. It extends onshore under the coastal town of Portrush and is buried <2.5-10 m below modern ground level. The identified paleo-landsurface is combined with sea-level curves from recent Glacio-Isostatic-Adjustment models to reconstruct marine transgression during the early-Mid-Holocene. Comparison is also made with reconstructions based on modern topography. Together, the identified paleo-landsurfaces and revised reconstructions can assist future site prospection on- and offshore and delimit high-potential areas for heritage management. Revised reconstructions also allow placement of extant archaeology into a more accurate context of landscape change and help develop insights into local-scale site location patterns. [ABSTRACT FROM AUTHOR]

Two new 14C dates from a bed of compact inter-tidal peat at Mill Strand, Portrush, are reported and discussed in relation to two previously obtained ages from peat at Dhu Varren, a short distance inland. The date from the top of the Mill Strand peat is statistically inseparable from that of the peat top at Dhu Varren. Together these dates indicate the cessation of peat growth occurred ~6950-6550 cal. BP as a result of sand deposition associated with sea-level rise. However, dated samples from deeper within the respective stratigraphies are not compatible. Their respective ages in relation to their elevations pose a problem of interpretation. [ABSTRACT FROM PUBLISHER]