scholarly journals Short-term disturbance by a commercial two-dimensional seismic survey does not lead to long-term displacement of harbour porpoises

2013 ◽  
Vol 280 (1771) ◽  
pp. 20132001 ◽  
Author(s):  
Paul M. Thompson ◽  
Kate L. Brookes ◽  
Isla M. Graham ◽  
Tim R. Barton ◽  
Keith Needham ◽  
...  

Assessments of the impact of offshore energy developments are constrained because it is not known whether fine-scale behavioural responses to noise lead to broader-scale displacement of protected small cetaceans. We used passive acoustic monitoring and digital aerial surveys to study changes in the occurrence of harbour porpoises across a 2000 km 2 study area during a commercial two-dimensional seismic survey in the North Sea. Acoustic and visual data provided evidence of group responses to airgun noise from the 470 cu inch array over ranges of 5–10 km, at received peak-to-peak sound pressure levels of 165–172 dB re 1 µPa and sound exposure levels (SELs) of 145–151 dB re 1 µPa 2 s −1 . However, animals were typically detected again at affected sites within a few hours, and the level of response declined through the 10 day survey. Overall, acoustic detections decreased significantly during the survey period in the impact area compared with a control area, but this effect was small in relation to natural variation. These results demonstrate that prolonged seismic survey noise did not lead to broader-scale displacement into suboptimal or higher-risk habitats, and suggest that impact assessments should focus on sublethal effects resulting from changes in foraging performance of animals within affected sites.

Geosciences ◽  
2020 ◽  
Vol 10 (7) ◽  
pp. 270 ◽  
Author(s):  
Vincent Gaffney ◽  
Simon Fitch ◽  
Martin Bates ◽  
Roselyn L. Ware ◽  
Tim Kinnaird ◽  
...  

Doggerland was a landmass occupying an area currently covered by the North Sea until marine inundation took place during the mid-Holocene, ultimately separating the British landmass from the rest of Europe. The Storegga Event, which triggered a tsunami reflected in sediment deposits in the northern North Sea, northeast coastlines of the British Isles and across the North Atlantic, was a major event during this transgressive phase. The spatial extent of the Storegga tsunami however remains unconfirmed as, to date, no direct evidence for the event has been recovered from the southern North Sea. We present evidence of a tsunami deposit in the southern North Sea at the head of a palaeo-river system that has been identified using seismic survey. The evidence, based on lithostratigraphy, geochemical signatures, macro and microfossils and sedimentary ancient DNA (sedaDNA), supported by optical stimulated luminescence (OSL) and radiocarbon dating, suggests that these deposits were a result of the tsunami. Seismic identification of this stratum and analysis of adjacent cores showed diminished traces of the tsunami which was largely removed by subsequent erosional processes. Our results confirm previous modelling of the impact of the tsunami within this area of the southern North Sea, and also indicate that these effects were temporary, localized, and mitigated by the dense woodland and topography of the area. We conclude that clear physical remnants of the wave in these areas are likely to be restricted to now buried, palaeo-inland basins and incised river valley systems.


2019 ◽  
Vol 58 (2) ◽  
pp. 315-337 ◽  
Author(s):  
Thomas Cogswell

AbstractHistorians have not paid close attention to the activities of freebooters operating out of Dunkirk in the late 1620s. This essay corrects that omission by first studying the threat from Dunkirk to England's east coast and then addressing how the central government, counties, and coastal towns responded. A surprisingly rich vein of manuscript material from Great Yarmouth and particularly from the Suffolk fishing community of Aldeburgh informs this case study of the impact of this conflict around the North Sea.


2021 ◽  
Vol 13 (15) ◽  
pp. 8159
Author(s):  
Joanna Przedrzymirska ◽  
Jacek Zaucha ◽  
Helena Calado ◽  
Ivana Lukic ◽  
Martina Bocci ◽  
...  

This paper examines the concept of maritime multi-use as a territorial/SPATIAL governance instrument for the enhancement of sustainable development in five EU sea basins. Multi-use (MU) is expected to enhance the productivity of blue economy sectors, as well as deliver additional socio-economic benefits related to the environmental and social dimensions of sustainable development. The paper provides a definition of maritime multi-use and identifies the multi-uses with the highest potential in EU sea basins. In each sea basin, multi-use plays a different role as concerns sustainable development. For the Eastern Baltic Sea, the Mediterranean Sea and the Black Sea, the MU focus should remain on the environmental pillar of sustainable development. In the North Sea, North Atlantic and Western Baltic Sea, addressing social sustainability seems a key precondition for success of MU in enhancement of sustainable spatial development at sea. Moreover, it has been suggested to introduce MU key global strategies such as SDGs or Macroregional strategies and action plans and to supplement maritime spatial planning with sectoral incentives and educational efforts as key vehicles supporting MU. The paper concludes by identifying aspects which, in order to inform maritime spatial planning and maritime governance regarding a more conscious application of the aforementioned concept, require further investigation. Key tasks are related to: more profound evaluation of performance of policies supporting MUs, researching the impact of MU on societal goals and on the MU costs and benefits, including external ones, and finally identifying the impact of MU on the development of various sectors and regions on land.


2018 ◽  
Vol 49 ◽  
pp. 00024
Author(s):  
Szymon Firląg

The aim of this paper is to present the results of measurements, on the quality of internal and external environment, carried out during the cruise of the tall ship STS Fryderyk Chopin. The cruise took place between 16th and 30th September 2017 as part of the scientific seminar of the Warsaw University of Technology (WUT) on the Wave, addressed to students of the WTU. After leaving the port of Edinburgh, crossing the North Sea, the Danish straits, stops in Copenhagen and Kołobrzeg, the tall ship reached Szczecin after two weeks. The measurements carried out on the deck included the temperature and relative humidity of the indoor air in three cabins and the men’s bathroom. In two cabins, the CO2 concentration was measured additionally. The outdoor temperature, relative humidity and concentration of PM 1.0, PM 2.5 and PM 10 were also measured. The obtained results allowed to assess the quality of the internal environment in accordance with the standards and to analyze the effectiveness of the mechanical ventilation system. Measurements of particulate matter have shown significant differences between outdoor air quality in the open sea and in ports or near major shipping routes. It turned out that the impact of emissions from passing ships using diesel engines is clearly visible.


2016 ◽  
Vol 13 (3) ◽  
pp. 841-863 ◽  
Author(s):  
H. Brenner ◽  
U. Braeckman ◽  
M. Le Guitton ◽  
F. J. R. Meysman

Abstract. It has been previously proposed that alkalinity release from sediments can play an important role in the carbonate dynamics on continental shelves, lowering the pCO2 of seawater and hence increasing the CO2 uptake from the atmosphere. To test this hypothesis, sedimentary alkalinity generation was quantified within cohesive and permeable sediments across the North Sea during two cruises in September 2011 (basin-wide) and June 2012 (Dutch coastal zone). Benthic fluxes of oxygen (O2), alkalinity (AT) and dissolved inorganic carbon (DIC) were determined using shipboard closed sediment incubations. Our results show that sediments can form an important source of alkalinity for the overlying water, particularly in the shallow southern North Sea, where high AT and DIC fluxes were recorded in near-shore sediments of the Belgian, Dutch and German coastal zone. In contrast, fluxes of AT and DIC are substantially lower in the deeper, seasonally stratified, northern part of the North Sea. Based on the data collected, we performed a model analysis to constrain the main pathways of alkalinity generation in the sediment, and to quantify how sedimentary alkalinity drives atmospheric CO2 uptake in the southern North Sea. Overall, our results show that sedimentary alkalinity generation should be regarded as a key component in the CO2 dynamics of shallow coastal systems.


Author(s):  
Ken P. Games ◽  
David I. Gordon

ABSTRACTSand waves are well known indicators of a mobile seabed. What do we expect of these features in terms of migration rates and seabed scour? We discuss these effects on seabed structures, both for the Oil and Gas and the Windfarm Industries, and consider how these impact on turbines and buried cables. Two case studies are presented. The first concerns a windfarm with a five-year gap between the planning survey and a subsequent cable route and environmental assessment survey. This revealed large-scale movements of sand waves, with the displacement of an isolated feature of 155 m in five years. Secondly, another windfarm development involved a re-survey, again over a five-year period, but after the turbines had been installed. This showed movements of sand waves of ∼50 m in five years. Observations of the scour effects on the turbines are discussed. Both sites revealed the presence of barchans. Whilst these have been extensively studied on land, there are few examples of how they behave in the marine environment. The two case studies presented show that mass transport is potentially much greater than expected and that this has implications for choosing turbine locations, the effect of scour, and the impact these sediment movements are likely to have on power cables.


2018 ◽  
Vol 156 (07) ◽  
pp. 1265-1284
Author(s):  
EVA VAN DER VOET ◽  
LEONORA HEIJNEN ◽  
JOHN J. G. REIJMER

AbstractIn contrast to the Norwegian and Danish sectors, where significant hydrocarbon reserves were found in chalk reservoirs, limited studies exist analysing the chalk evolution in the Dutch part of the North Sea. To provide a better understanding of this evolution, a tectono-sedimentary study of the Late Cretaceous to Early Palaeogene Chalk Group in the northern Dutch North Sea was performed, facilitated by a relatively new 3D seismic survey. Integrating seismic and biostratigraphic well data, seven chronostratigraphic units were mapped, allowing a reconstruction of intra-chalk geological events.The southwestward thickening of the Turonian sequence is interpreted to result from tilting, and the absence of Coniacian and Santonian sediments in the western part of the study area is probably the result of non-deposition. Seismic truncations show evidence of a widespread inversion phase, the timing of which differs between the structural elements. It started at the end of the Campanian followed by a second pulse during the Maastrichtian, a new finding not reported before. After subsidence during the Maastrichtian and Danian, renewed inversion and erosion occurred at the end of the Danian. Halokinesis processes resulted in thickness variations of chalk units of different ages.In summary, variations in sedimentation patterns in the northern Dutch North Sea relate to the Sub-Hercynian inversion phase during the Campanian and Maastrichtian, the Laramide inversion phase at the end of the Danian, and halokinesis processes. Additionally, the Late Cretaceous sea floor was characterized by erosion through contour bottom currents at different scales and resedimentation by slope failures.


1972 ◽  
Vol 1 (13) ◽  
pp. 131
Author(s):  
A.J. Van Rees ◽  
P. Can der Kuur ◽  
H.J. Stroband

To guide -the works for the new harbour entrance at Rotterdam- Europoort in 1965 a tidal salinity model (scales 1:640 hor., 1:64 vert.) was constructed. The model includes a part of the North Sea and the Rotterdam Waterway Estuary. For its regular adjustment, use could be made of extensive prototype measurements, two-dimensional tidal computations and tidal computations by means of the DELTAR (analogue, onedim.). The model has proved to be very valuable for predicting stream patterns for nautical purposes because the shipping (huge crude carriers) had to go on without danger while the works were being carried out. The model has also been used for the solution of harbour problems (design, siltation), for predicting cooling water recirculation, and for advice on salinity intrusion problems.


2021 ◽  
Author(s):  
Bolin Xu ◽  
Qing He ◽  
Kwok Pan Chun ◽  
Julian Klaus ◽  
Rémy Schoppach ◽  
...  

<p>Teleconnections relate regional pressure patterns to local climate anomalies, influencing the variation of vegetation patterns. Over west continental Europe, droughts have been widely investigated with persistent low-frequency atmospheric circulation patterns (e.g. the North Atlantic Oscillation, NAO) with the centers over the Atlantic based on the 500mb height anomalies of the Northern Hemisphere. However, the effects of teleconnection patterns with the centers of active variability over the North and Caspian Seas is largely unexplored for droughts related to vegetation patterns. In this study, we explored the impact of the North Sea-Caspian Pattern (NCP) on regional ecohydrologic conditions in the Greater Region of Luxembourg in Western Europe. Using a Principal Component Analysis (PCA), we first decomposed the annual Normalized Difference Vegetation Index (NDVI) from the Global Inventory Monitoring and Modeling System (GIMMS) between 1981 and 2015. In the first PCA component, a distinctive greening trend of NDVI is detected since the late 1980s. However, the corresponding station observations and the ERA5 reanalysis data show that the region in west continental Europe became increasingly drier based on the difference between precipitation and evaporation. We explain the above paradoxical greening but drying patterns by the mechanism of NCP over the region. During the positive phase of NCP, the high pressure over the North Sea weakens circulation over the region and leads to warmer conditions in west continental Europe. These conditions are good for vegetation growth because the region was mainly energy-limited during the observed period at the annual scale based on a Budyko analysis. However, the positive phase of NCP also promotes divergent conditions at the lower troposphere and it reduces moisture flux over the region. In the Budyko space, the persistent positive phase of NCP would lead the energy-limited region to be water-limited. As the positive phase of NCP is expected to be more frequent along with the increasing global temperatures, the region may start to experience increasing water stress on vegetation. These results suggest that unforeseen droughts related to vegetation may be emerging in the region. New drought monitoring and management measures related to vegetation should be developed at west continental Europe, especially during the positive phase of NCP.</p>


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