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Shipwrecks are an integral part of our maritime archaeological landscape and are associated with diverse societal and cultural interests, yielding significant management challenges. Coupled hydrodynamic and geomorphological processes significantly impact the effective in situ preservation of these fragile sites. In this study, we assess sediment budget change and hydrodynamic triggers at metal‐hulled shipwrecks lost between 1875 and 1918, all located in the tidally dominated Irish Sea at depths between 26 and 84 m. This is conducted using time‐lapse, multibeam echosounder surveys at multiannual, annual, and weekly time steps, supported by sediment grain‐size analysis, modeled ocean currents, and shallow seismic data. Results indicate significant changes at all time steps for sites located in sand‐dominated environments, whereas the seabed around shipwrecks settled in multimodal sediments shows virtually no change outside of measurement errors (±30 cm). Variability in geomorphic change is attributed to local environmental factors, including bed shear stress, sediment supply, and spatial barriers to scour. We demonstrate that individual wrecks in similar shelf sea regions can be in very different equilibrium states, which has critical implications for the in situ management of underwater cultural heritage. [ABSTRACT FROM AUTHOR]

Near-death experiences (NDEs) are usually characterized as pleasant or positive experiences, but little research to date has involved quantification of the sentiment contained in experiencers' descriptions of their NDEs. In this study, I undertook an automated method of obtaining a corpus of 557 NDE narratives by web scraping and then using lexicon-based sentiment analysis to assign a sentiment score to each narrative. The results showed that NDEs are more often associated with positive sentiment than negative sentiment, with twice as many narratives receiving a positive overall sentiment score as a negative one. Although just under 3% of the sample contained descriptions of wholly unpleasant NDEs, many NDE narratives contained at least some negative sentiment, usually associated with the circumstances of the NDE but sometimes with the experience itself, most commonly involving the decision to return or 'go back' to the body. Future researchers should consider using aspect level sentiment analysis with a modified lexicon to more accurately quantify the sentiment contained in NDE narratives. [ABSTRACT FROM AUTHOR]

The interplay of eustatic and isostatic factors causes complex relative sea‐level (RSL) histories, particularly in paraglacial settings. In this context the past record of RSL is important in understanding ice‐sheet history, earth rheology and resulting glacio‐isostatic adjustment. Field data to develop sea‐level reconstructions are often limited to shallow depths and uncertainty exists as to the veracity of modelled sea‐level curves. We use seismic stratigraphy, 39 vibrocores and 26 radiocarbon dates to investigate the deglacial history of Belfast Lough, Northern Ireland, and reconstruct past RSL. A typical sequence of till, glacimarine and Holocene sediments is preserved. Two sea‐level lowstands (both max. −40 m) are recorded at c. 13.5 and 11.5k cal a bp. Each is followed by a rapid transgression and subsequent periods of RSL stability. The first transgression coincides temporally with a late stage of Meltwater Pulse 1a and the RSL stability occurred between c. 13.0 and c. 12.2k cal a bp (Younger Dryas). The second still/slowstand occurred between c. 10.3 and c. 11.5k cal a bp. Our data provide constraints on the direction and timing of RSL change during deglaciation. Application of the Depth of Closure concept adds an error term to sea‐level reconstructions based on seismic stratigraphic reconstructions. [ABSTRACT FROM AUTHOR]

Species distribution models (SDMs) are commonly used to model the spatial structure of species in the marine environment, however, most fail to account for detectability of the target species. This can result in underestimates of occupancy, where nondetection is conflated with absence. The site occupancy model (SOM) overcomes this failure by treating occupancy as a latent variable of the model and incorporates a detection submodel to account for variability in detection rates. These have rarely been applied in the context of marine fish and never for the multiseason dynamic occupancy model (DOM). In this study, a DOM is developed for a designated species of concern, cusk (Brosme brosme), over a four‐season period. Making novel use of a high‐resolution 3‐dimensional hydrodynamic model, detectability of cusk is considered as a function of current speed and algae cover. Algal cover on the seabed is measured from video surveys to divide the study area into two distinct regions: those with canopy forming species of algae and those without (henceforth bottom types). Modeled estimates of the proportion of sites occupied in each season are 0.88, 0.45, 0.74, and 0.83. These are significantly greater than the proportion of occupied sites measured from underwater video observations which are 0.57, 0.28, 0.43, and 0.57. Individual fish are detected more frequently with increasing current speed in areas lacking canopy and less frequently with increasing current speed in areas with canopy. The results indicate that, where possible, SDM studies for all marine species should take account of detectability to avoid underestimating the proportion of sites occupied at a given study area. Sampling closed areas or areas of conservation often requires the use of nonphysical, low impact sampling methods like camera surveys. These methods inherently result in detection probabilities less than one, an issue compounded by time‐varying features of the environment that are rarely accounted for marine studies. This work highlights the use of modeled hydrodynamics as a tool to correct some of this imbalance. Detection of marine fish is often not considered when mapping their distributions. This study considers detectability as a function of hydrodynamics and bottom type. Findings show how considering detection probability affects occupancy estimates for marine fish in an area of conservation for a priority species. [ABSTRACT FROM AUTHOR]

Introduction: International reports suggest there have been prehospital delays for time-sensitive emergencies like stroke and TIA during the COVID-19 pandemic. The aim was to investigate the impact of the COVID-19 pandemic on ambulance times and emergency call volume for adults with suspected stroke and TIA in Ireland. Method: We conducted a retrospective cohort study of patients ≥ 18 years with suspected stroke/TIA, based on data from the National Ambulance Service. We included all cases assigned code 28 (suspected stroke/TIA) by the emergency call-taker, from 2018-2021. We compared ambulance times and emergency call volume by week, the four COVID-19 waves (defined by the Health Protection Surveillance Centre) and annually. The COVID-19 period was from March 1, 2020 - December 19, 2021 and the pre-COVID-19 period January 1, 2018 - February 29, 2020. Continuous variables were compared with t-tests and categorical variables with Pearson's χ2 tests. Results: 40,012 cases were included: 20,281 in the pre-COVID-19 period and 19,731 in the COVID-19 period. Mean patient age significantly decreased between the two periods, from 71 years (±16.5) to 69.8 years (±17.1); p<0.001. Mean ambulance response time increased between the two periods from 17 minutes 31 seconds to 18 minutes 59 seconds (p<0.001). The number of cases with symptom onset to emergency call time of >4 hours significantly increased from 5,581 to 6,060 during the COVID-19 period (p<0.001). Mean calls/day increased from 25.1/day to 30.1/day during the COVID-19 period. Conclusion: Early findings from the study suggest an increase in call volume for stroke/TIA between the COVID-19 and pre-COVID-19 periods. An increase in response times during the same periods was also found. We concluded that longer symptom-to-call times indicate a change in healthcare-seeking behavior. Sustaining high levels of compliance with stroke code protocols is crucial during healthcare crises. Future research will involve further analysis including controlling for confounders. [ABSTRACT FROM AUTHOR]

In January 2001, a team of researchers from the University of Ulster (Northern Ireland) conducted an innovative maritime archaeology project on the East African coast in partnership with the British [...]

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]

The large number of historic metal-hulled shipwrecks on the seabed is a major consideration for the marine environment, heritage management and spatial planning. Their stability is driven by linked hydro- and sediment-dynamics, which in turn influence chemical corrosion and biological encrustation. The dynamism at underwater sites is frequently expressed in elaborate patterns of depositional and erosional features developed due to seabed scour. These settings are complex, due to the variable morphologies of the wrecks, and diverse types of seabed geology and geomorphology. Not only are the flow patterns and geomorphic changes at shipwreck sites not fully understood, but how these influence the wreck structures remains under-researched. Here we combine high-resolution multibeam echosounder, ocean current and sediment data with 3D Computational Fluid Dynamics (CFD) to investigate interrelations between hydro- and sediment-dynamics and the deterioration of two complex, fully submerged tidally-influenced shipwrecks. Intricate patterns of wake and horseshoe vortices are observed, and modelled wall shear stresses predict geomorphic changes recorded in 4-year and one-week interval difference models. Moreover, substantial damage is detected on the wrecks, correlated with areas of elevated wall shear stress and pressure in CFD simulations. The combined approach aids site management and provides analogies for offshore engineering. • The sheer number of metal shipwrecks on the seabed creates perplexing management challenges. • Their structures significantly influence, and are influenced by, the local hydro- and sediment-dynamic settings. • Computational fluid dynamics and difference modelling using bathymetric data provide new insights into wreck deterioration. • Intricate patterns of simulated flows and wall shear stresses correspond to the areas of sediment erosion and deposition. [ABSTRACT FROM AUTHOR]

The Maidens (including the North and Outer Klondyke) are a group of bedrock extrusions about 14 km northeast of Larne, off the coast of Northern Ireland (central point for Maidens Complex: 54°57'50.0, 25°42'20.0). Multibeam echosounder data have been combined with extensive ground-truthing to produce broad-scale substratum and biotope maps for the site. The bathymetry was used to derive rasters of slope gradient, rugosity, aspect, and fine- and broad-scale benthic position index which were used for further analyses with Principal Components Analysis. Ground-truthing data were used to create sample signatures and a Maximum Likelihood Analysis performed to classify the surfaces according to that signature. The supervised classifications generated distributions for three broad-scale substrata and habitat biotopes (six level three biotopes, four level four and one level five biotope). The maps provide critical information and distributions that greatly facilitate the conservation, management and monitoring of a proposed Special Area of Conservation. [ABSTRACT FROM AUTHOR]

A 1:30,000 substratum map for an area off the north coast of Ireland is presented. The study area is bounded in the south by the Causeway coastline and in the north by the following coordinates: top left corner (6°43'36''W, 55°17'N) and top right corner (6°27'W, 55°17'N). This mapping has been made possible through the availability of full seafloor coverage multibeam swath bathymetry and backscatter data (both gridded to 1 m), together with ground-truthing data collected over the past 40 years. Bathymetry data were used to generate terrain indices such as slope, rugosity, aspect, fine- and broad-scale Benthic Position Index, whilst the backscatter data were interpreted visually, subjected to an unsupervised classification process using QTC Multiview, and combined with the bathymetry-derived parameters into a clustermap in ArcGIS. The resulting maps allowed us to divide the seabed into 10 distinct acoustic classes, which, linked to sediment samples, diver surveys, underwater video-tows and remotely operated vehicle surveys, were converted into a substratum map. This is the most accurate seafloor substratum map to date for the north coast of Ireland and could form the basis for more in-depth geological, biological and hydrodynamic studies of this highly dynamic coastline. [ABSTRACT FROM AUTHOR]

This paper outlines work currently being undertaken to reconstruct submerged archaeological landscapes off the north coast of Ireland. This research uses the recently-completed Joint Irish Bathymetric Survey (JIBS), which has provided full-coverage high-resolution multibeam bathymetric data for the sea-bed off the north coast. This data has been examined for evidence of past sea-level change and been used to produce palaeo-geographic reconstructions of the past landscape, which in turn have facilitated the identification of ten areas of high archaeological potential. The results presented here will form the basis of a future programme of archaeological survey and prospection. © 2010 The Authors [ABSTRACT FROM AUTHOR]

This paper describes Phase 1 of the project 'Archaeological Applications of the Joint Irish Bathymetric Survey (JIBS) Data', analysing bathymetric and backscatter data derived from multibeam surveys off the north coast of Ireland. In particular, the usability of the data for shipwreck detection, identification and site characterization is explored. In Phase 1, the data was screened for anomalous sea-bed features, which were subsequently described, catalogued and categorized according to their archaeological potential and cross-referenced against existing records. A planned second phase of this project will examine each anomaly in greater detail together with the local and regional hydrodynamic conditions. © 2010 The Authors [ABSTRACT FROM AUTHOR]

Please clickhereto download the map associated with this article. Multibeam echosounder data collected by the Irish National Seabed Survey (INSS) between 2000 and 2001 in the Rockall Trough have been used by many projects to analyze the geomorphology and the sedimentary processes of the margins of the Trough. However, due to the low spatial resolution of 150–250 m and the amount of artefacts still embedded in the publicly available data, many geomorphological features have been overlooked. This paper shows that the same multibeam dataset can provide more detailed information on seabed processes when the latest hydrographic and backscatter post-processing techniques are used to reduce data artefacts and improve data quality and spatial resolution. The resulting map, presented here at a scale of 1:450,000, is based on a semi-automatic and manual interpretation of geomorphological features highlighted using a new and improved 30 m bathymetric grid and a multibeam backscatter mosaic obtained using the GEOCODER post-processing algorithm. Overall, the map shows a complex sedimentological scenario where the Rockall Bank Mass Flow failure, the Donegal-Barra trough-mouth fan, along slope structures such as the Feni Contourite Drift and the Porcupine moat dominate the Rockall Trough flanks and basin floor. Smaller features such as canyon and gully systems, escarpments, coral mounds, volcanic mounds and iceberg scours have also been mapped in detail. In addition, the interpretation of the backscatter mosaic allows for the first time the identification of depositional lobes generated by downslope mass transport and canyon drainage systems, particularly where these features completely lose their bathymetric expression. [ABSTRACT FROM PUBLISHER]