Seal movements in tidal stream environments: Novel methods and ecological insights for the tidal stream turbine industry

2021 ◽  
Author(s):  
◽  
William P. Kay

With the increasing threats of climate change, there is an ever-pressing need to reduce fossil fuel emissions. Thus, recent years have seen a dramatic increase in the development of marine renewable energy (MRE) devices – in particular tidal stream turbines (TSTs) – to exploit tidal stream environments (TSEs) for green electricity generation. However, TSTs may pose threats to marine megafauna and relatively little is known about how animals operate in the environments targeted by these devices, and how they may be affected by them. This information is crucial for informing appropriate management strategies to mitigate the risk of conflict between animals and TST developments. Here, using grey seals (Halichoerus grypus) and harbour seals (Phoca vitulina) as my study species, with data collected from around the UK and neighbouring waters, including the Celtic and the North Sea, I aim to understand and quantify how seals move in TSEs and the implications of this for the TST industry. To achieve this, I quantify the broad-scale movement patterns of seals in coastal waters and their overlap with TSTs, examine the fine-scale movement and behaviour of seals in response to tidal conditions, derive recommendations on sample size and recording duration for animal tracking studies, and design new tags to track seals in TSEs at very fine-scales whilst minimising tag impact. My results suggest that the movements and behaviour of seals are driven by a combination of measurable (and in some cases predictable) demographic and environmental factors, and that the conservation strategies developed to manage the interaction between individuals and populations with TST devices must consider site-specific differences and account for individual variation, with consequences regarding data requirements. Further investigation is required to fully elucidate the extent of variability of seal movements in TSEs and the threats of TST developments, however the research presented herein provides new tools and ecological insights to support this need for both researchers and practitioners.

2021 ◽  
Vol 36 (1) ◽  
pp. 155-164
Author(s):  
Richard Barnes

Abstract On 30 September 2020, the United Kingdom and Norway signed the Framework Agreement on Fisheries that will provide the basis for future cooperation in the sustainable management of their fisheries. The Agreement is the first such agreement adopted by the UK following its decision to the leave the European Union. This note provides some background to the Agreement and examines its key features. Whilst the content of the Agreement appears to be rather basic, this is broadly consistent with other framework agreements, and it does provide some insight into the direction and focus of fisheries management in the North Sea, and how cooperation may develop between coastal States and the European Union.


2017 ◽  
Vol 57 (2) ◽  
pp. 498
Author(s):  
Mike Lynn ◽  
Alan Samuel

In the last 12 months or so, particularly with the drop in oil price, there’s been a lot of speculation about the future of the Australian oil and gas industry. Strenuous efforts are being made to bring down costs, reduce complexity and expedite the completion of major capital projects. Yet with the commodity price looking likely to be subdued for some time, serious questions persist. How can we sustain activity in Australia, secure the investment needed to continue exploration and appraisal drilling, for the next wave of projects? In looking for answers to these challenges, collaboration is a theme that comes up time and time again. But what does it actually mean? What does it look like in practice? Who does it well and how? And which companies are reaping the rewards of great collaboration? To fill this knowledge gap we are launching a survey which will look at many aspects of collaboration in the Australia and compare this with the results of similar surveys conducted in the UK. We will be looking to survey both operators and service companies working in the Australia and find out: What does collaboration mean? What constitutes effective collaboration? How do companies view themselves and each other as collaborators? How does collaboration in Australia compare with companies in the North Sea? We hope a better understanding of collaboration could help companies in Australia continue to improve productivity and efficiency, adopt new ways of working, and truly make the most of Australia’s abundant resources.


2015 ◽  
Vol 55 (2) ◽  
pp. 453
Author(s):  
Scott Sivewright ◽  
Markus Hulke ◽  
Goh Teck Hua

Heightened focus on wellbore integrity in the high-profile offshore arena has signaled the need for integrated solutions that deliver greater operational efficiency, safety, reliability and cost savings. Innovative systems that can interface with the existing rig package and facilitate mechanised processes are critical to operator needs to maximise safety and efficiency. A rig integration operation to run tubulars and make up connections for a multi-well project in the UK sector of the North Sea reduced overall operational costs without compromising performance. This operation combined remote-controlled mechanised power tongs (maximum 100,000 ft/lb) with a software package that recorded, analysed and evaluated critical torque-turn data in a real-time report, which could be viewed from multiple remote locations. This hands-off system ensured the integrity of the connections, eliminating the possibility of tubing damage and reducing tripping. The technology performed risky activities in a mechanised fashion, increased efficiency, reduced non-productive time and kept workers safer. This approach is particularly suited to the offshore sector, which is defined by high costs and risks, specifically the use of high-torque strings where casing-running operations present potential hazards. The North Sea’s stringent safety standards dictate the need for a totally integrated methodology that provides a control system, and handling and makeup tools that can easily interface with existing rig equipment. This extended abstract will review the evolution of connection integrity and remote monitoring to enhance safety and well integrity in offshore environments. It will also discuss the latest technologies and software in connection make up and their impact on improving operational efficiency.


Author(s):  
Luis F. Batalla Toro ◽  
Simon L. Reid ◽  
Alfredo Salcines Tudela ◽  
Duncan Graham

Between 1969 and 1977, eleven semisubmersible drilling platforms were designed and built with an innovative pentagon shaped hull, specifically to work in the harsh environment of the North Sea. One of the drilling rigs, the Alexander L. Kielland, was converted soon after construction into an accommodation platform (flotel) and failed catastrophically in 1980. Another, the Pentagon 83 “Drillmaster” (renamed as Buchan Alpha), was being converted to a Floating Production Unit at the time of the disaster. The structure of Buchan Alpha was significantly modified during the conversion of the platform so that it benefited from the lessons learnt following the Alexander L. Kielland accident to ensure that the same sequence of events could not be repeated. This technical paper objective is to explain the integrated decommissioning process of the Buchan Alpha in the UK after more than 40 years since being built and more than 35 years of successful operation since it was converted to a Floating Production Unit, and how the features of its original design have accompanied the platform through the decommissioning process. The scope covers all phases of Buchan Alpha decommissioning from the detailed planning and preparation, the suspension of production up to the dismantling and recycling process. Significant challenges for the decommissioning team included the requirement to preserve the operational status of the subsea infrastructure for potential future field redevelopment and the diver disconnection of the subsea wells. Buchan Alpha’s deep draught presented limitations on the selection of dismantling and recycling yards due to quayside water depths. Complex ballasting operations and removal of the thruster’s propellers were required to facilitate the platform berthing at the quayside. Key lessons learned applicable for future decommissioning of floating production facilities will be shared.


2020 ◽  
Vol 77 (5) ◽  
pp. 1772-1786 ◽  
Author(s):  
A D Rijnsdorp ◽  
J G Hiddink ◽  
P D van Denderen ◽  
N T Hintzen ◽  
O R Eigaard ◽  
...  

Abstract Fisheries using bottom trawls are the most widespread source of anthropogenic physical disturbance to seafloor habitats. To mitigate such disturbances, the development of fisheries-, conservation-, and ecosystem-based management strategies requires the assessment of the impact of bottom trawling on the state of benthic biota. We explore a quantitative and mechanistic framework to assess trawling impact. Pressure and impact indicators that provide a continuous pressure–response curve are estimated at a spatial resolution of 1 × 1 min latitude and longitude (∼2 km2) using three methods: L1 estimates the proportion of the community with a life span exceeding the time interval between trawling events; L2 estimates the decrease in median longevity in response to trawling; and population dynamic (PD) estimates the decrease in biomass in response to trawling and the recovery time. Although impact scores are correlated, PD has the best performance over a broad range of trawling intensities. Using the framework in a trawling impact assessment of ten métiers in the North Sea shows that muddy habitats are impacted the most and coarse habitats are impacted the least. Otter trawling for crustaceans has the highest impact, followed by otter trawling for demersal fish and beam trawling for flatfish and flyshooting. Beam trawling for brown shrimps, otter trawling for industrial fish, and dredging for molluscs have the lowest impact. Trawling is highly aggregated in core fishing grounds where the status of the seafloor is low but the catch per unit of effort (CPUE) per unit of impact is high, in contrast to peripheral grounds, where CPUE per unit of impact is low.


2018 ◽  
Vol 18 (4) ◽  
pp. 330-344 ◽  
Author(s):  
Trude Klevan ◽  
Bengt Karlsson ◽  
Lydia Turner ◽  
Nigel Short ◽  
Alec Grant

Purpose The purpose of this paper is to explore how sharing stories of being a mental health professional and academic, based more broadly on serendipity and searching in life, can serve as means for bridging and developing cross-cultural understandings and collaborative work. Design/methodology/approach This paper is a relational autoethnography based on face-to-face and written conversational dialogue between five mental health academics from the UK and Norway. Findings The very practice of writing this paper displays and serves the purpose of bridging people, cultures and understandings, at several levels, in the facilitation of new research and writing projects. Troubling traditional boundaries between “us” and “them, and the “knower” and the “known,” the writing is theoretically underpinned by Friendship as Method, situated in a New Materialist context. Originality/value Through its conversational descriptions and explorations the paper shows how doing relational autoethnography can be purposeful in developing cross-cultural understandings and work at both professional and personal levels. It also demonstrates how autoethnography as relational practice can be useful in the sharing of this methodology between people who are more and less familiar with it.


Author(s):  
M.N Tsimplis ◽  
D.K Woolf ◽  
T.J Osborn ◽  
S Wakelin ◽  
J Wolf ◽  
...  

Within the framework of a Tyndall Centre research project, sea level and wave changes around the UK and in the North Sea have been analysed. This paper integrates the results of this project. Many aspects of the contribution of the North Atlantic Oscillation (NAO) to sea level and wave height have been resolved. The NAO is a major forcing parameter for sea-level variability. Strong positive response to increasing NAO was observed in the shallow parts of the North Sea, while slightly negative response was found in the southwest part of the UK. The cause of the strong positive response is mainly the increased westerly winds. The NAO increase during the last decades has affected both the mean sea level and the extreme sea levels in the North Sea. The derived spatial distribution of the NAO-related variability of sea level allows the development of scenarios for future sea level and wave height in the region. Because the response of sea level to the NAO is found to be variable in time across all frequency bands, there is some inherent uncertainty in the use of the empirical relationships to develop scenarios of future sea level. Nevertheless, as it remains uncertain whether the multi-decadal NAO variability is related to climate change, the use of the empirical relationships in developing scenarios is justified. The resulting scenarios demonstrate: (i) that the use of regional estimates of sea level increase the projected range of sea-level change by 50% and (ii) that the contribution of the NAO to winter sea-level variability increases the range of uncertainty by a further 10–20 cm. On the assumption that the general circulation models have some skill in simulating the future NAO change, then the NAO contribution to sea-level change around the UK is expected to be very small (<4 cm) by 2080. Wave heights are also sensitive to the NAO changes, especially in the western coasts of the UK. Under the same scenarios for future NAO changes, the projected significant wave-height changes in the northeast Atlantic will exceed 0.4 m. In addition, wave-direction changes of around 20° per unit NAO index have been documented for one location. Such changes raise the possibility of consequential alteration of coastal erosion.


2003 ◽  
Vol 20 (1) ◽  
pp. 761-770 ◽  
Author(s):  
A. P. Hillier

AbstractDiscovered in 1966 and starting production in 1968, Leman was the second gas field to come into production in the UK sector of the North Sea and is still producing gas today. It is classified as a giant field with an estimated initial gas-in-place of 397 BCM of gas in the aeolian dune sands of the Rotliegend Group. The field extends over five blocks and is being developed by two licence groups with Shell and Amoco (now BP Amoco) being the operators


Author(s):  
J.W. Horwood ◽  
R.S. Millner

Large catches of sole (Solea solea) were made in early 1996 from the south-western North Sea. Sole suffer physiological damage in waters below 3–4 C. In February 1996 cold water of 3–4 C unusually extended from the Continental coast onto the Dogger Bank. It is likely that the increased catches were due to the consequential distribution and behaviour of the sole, making them more susceptible to capture.Exceptionally large catches of mature sole (Solea solea (L.)) were made in February 1996 by Lowestoft fishermen from the south-western North Sea. Surprisingly this was not welcome. The UK allocation of the North Sea sole is -4 % of the EU Total Allowable Catch (TAC), and fishermen are restricted nationally, and by the fishing companies, to a tightly managed ration. The Lowestoft Journal (8 March 1996) reported the suspension of a local fishing skipper for not throwing back 5000 kg of sole caught in the Silver Pits. We will show that the abnormal catches were due to exceptionally cold waters.Sole in the North Sea are at the northern extremity of their range, with sole seldom living in waters below 5°C (Horwood, 1993). In fact, North Sea sole were successfully introduced into Lake Quarun, Egypt, where they lived in temperatures in excess of 30°C (El-Zarka, 1965). Young sole migrate from their shallow inshore nursery grounds, such as the Waddensea, as winter approaches (Creutzberg & Fonds, 1971).


2017 ◽  
Vol 200 ◽  
pp. 75-100 ◽  
Author(s):  
T. Sherwen ◽  
M. J. Evans ◽  
R. Sommariva ◽  
L. D. J. Hollis ◽  
S. M. Ball ◽  
...  

Halogens (Cl, Br) have a profound influence on stratospheric ozone (O3). They (Cl, Br and I) have recently also been shown to impact the troposphere, notably by reducing the mixing ratios of O3 and OH. Their potential for impacting regional air-quality is less well understood. We explore the impact of halogens on regional pollutants (focussing on O3) with the European grid of the GEOS-Chem model (0.25° × 0.3125°). It has recently been updated to include a representation of halogen chemistry. We focus on the summer of 2015 during the ICOZA campaign at the Weybourne Atmospheric Observatory on the North Sea coast of the UK. Comparisons between these observations together with those from the UK air-quality network show that the model has some skill in representing the mixing ratios/concentration of pollutants during this period. Although the model has some success in simulating the Weybourne ClNO2 observations, it significantly underestimates ClNO2 observations reported at inland locations. It also underestimates mixing ratios of IO, OIO, I2 and BrO, but this may reflect the coastal nature of these observations. Model simulations, with and without halogens, highlight the processes by which halogens can impact O3. Throughout the domain O3 mixing ratios are reduced by halogens. In northern Europe this is due to a change in the background O3 advected into the region, whereas in southern Europe this is due to local chemistry driven by Mediterranean emissions. The proportion of hourly O3 above 50 nmol mol−1 in Europe is reduced from 46% to 18% by halogens. ClNO2 from N2O5 uptake onto sea-salt leads to increases in O3 mixing ratio, but these are smaller than the decreases caused by the bromine and iodine. 12% of ethane and 16% of acetone within the boundary layer is oxidised by Cl. Aerosol response to halogens is complex with small (∼10%) reductions in PM2.5 in most locations. A lack of observational constraints coupled to large uncertainties in emissions and chemical processing of halogens make these conclusions tentative at best. However, the results here point to the potential for halogen chemistry to influence air quality policy in Europe and other parts of the world.


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