Long-term Behavior of CO2 Stored on a Large Scale in the Utsira Formation, the North Sea, Norwegian Continental Shelf

Abstract. We investigate the long-term variability of extreme high sea levels (ESL) in the southern German Bight and associated large-scale forcing mechanisms in the climate system using simulations covering the last 1000 years. To this end, global MPI-ESM simulations from the PMIP3 past1000 project are dynamically scaled-down with a regionally coupled climate system model focusing on the North Sea. We find that the statistics of simulated ESL compare well with observations from the tide gauge record at Cuxhaven but show large variations on interannual to centennial timescales. ESL arise independent of preferred systematic oscillations and are to a large extent decoupled from variations of the background sea level (BSL). Large scale circulation regimes associated with periods of high ESL are regionally consistent and similar to those associated with elevated BSL, but the location of the respective centers of action of the governing sea level pressure (SLP) dipole differs. While BSL variations correlate well with the wintertime North Atlantic Oscillation (NAO), ESL variations are rather associated with a dipole between northeastern Scandinavia and the Gulf of Biscay, leading to a stronger local north-westerly wind component in the North Sea. Potential links with solar or volcanic forcing are masked due to the high ESL variability. The high internal variability stresses the irreducible uncertainties related to traditional extreme value estimates based on shorter subsets which fail to account for long-term variations. Existing estimates of future changes in ESL may be dominated by natural variability rather than climate change signals, thus requiring larger ensemble simulations to assess future flood risks.

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Reconstructing three decades of total international trawling effort in the North Sea

10.5194/essd-2019-90 ◽

2019 ◽

Author(s):

Elena Couce ◽

Michaela Schratzberger ◽

Georg H. Engelhard

Keyword(s):

North Sea ◽

Large Scale ◽

Information Source ◽

Marine Ecosystem ◽

Fishing Effort ◽

Anthropogenic Pressures ◽

The North ◽

The North Sea ◽

Long Term Impact

Abstract. Fishing – especially trawling – is one of the most ubiquitous anthropogenic pressures on marine ecosystems worldwide, yet very few long-term, spatially explicit datasets on trawling effort exist; this greatly hampers our understanding of the medium- to long-term impact of trawling. This important gap is addressed here for the North Sea, a highly productive shelf sea which is also subject to many anthropogenic pressures. For a 31-year time span (1985–2015), we provide a dataset on the spatial distribution of total international otter and beam trawling effort, for all ICES rectangles (0.5° latitude by 1° longitude) of the North Sea. The dataset was largely reconstructed using compiled effort data from 7 fishing effort time-series, each covering shorter time spans and some of the countries fishing the North Sea only. For the years where effort data for particular countries were missing, the series was complemented using estimated (modelled) effort data. This new, long-term and large-scale trawling dataset may serve the wider scientific community, as well as those involved with policy and management, as a valuable information source on fishing pressure in a Large Marine Ecosystem which is heavily impacted, but which simultaneously provides a wealth of ecosystem services to society. The dataset is available on the Cefas Data Hub at: https://doi.org/10.14466/CefasDataHub.61 (Couce et al., 2019).

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Reconstructing three decades of total international trawling effort in the North Sea

Earth System Science Data ◽

10.5194/essd-12-373-2020 ◽

2020 ◽

Vol 12 (1) ◽

pp. 373-386 ◽

Cited By ~ 3

Author(s):

Elena Couce ◽

Michaela Schratzberger ◽

Georg H. Engelhard

Keyword(s):

North Sea ◽

Large Scale ◽

Information Source ◽

Marine Ecosystem ◽

Fishing Effort ◽

Anthropogenic Pressures ◽

The North ◽

The North Sea ◽

Long Term Impact

Abstract. Fishing – especially trawling – is one of the most ubiquitous anthropogenic pressures on marine ecosystems worldwide, yet very few long-term, spatially explicit datasets on trawling effort exist; this greatly hampers our understanding of the medium- to long-term impact of trawling. This important gap is addressed here for the North Sea, a highly productive shelf sea which is also subject to many anthropogenic pressures. For a 31-year time span (1985–2015), we provide a gridded dataset of the spatial distribution of total international otter and beam trawling effort, with a resolution of 0.5∘ latitude by 1∘ longitude, over the North Sea. The dataset was largely reconstructed using compiled effort data from seven fishing effort time series, each covering shorter time spans and only some of the countries fishing the North Sea. For the years where effort data for particular countries were missing, the series was complemented using estimated (modelled) effort data. This new, long-term and large-scale trawling dataset may serve the wider scientific community, as well as those involved with policy and management, as a valuable information source on fishing pressure in a large marine ecosystem which is heavily impacted but which simultaneously provides a wealth of ecosystem services to society. The dataset is available on the Cefas Data Hub at: https://doi.org/10.14466/CefasDataHub.61, version 2 (Couce et al., 2019).

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Long Term Changes in Wind and Wave Climate on the North Sea

Coastal Engineering 1990 ◽

10.1061/9780872627765.144 ◽

1991 ◽

Author(s):

Frank M. J. Hoozemans

Keyword(s):

North Sea ◽

Wave Climate ◽

The North ◽

Long Term Changes ◽

The North Sea

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Offshore Claims and Problems in the North Sea

The American Journal of International Law ◽

10.2307/2196753 ◽

1965 ◽

Vol 59 (3) ◽

pp. 505-522 ◽

Cited By ~ 5

Author(s):

Richard Young

Keyword(s):

North Sea ◽

Large Scale ◽

Geneva Convention ◽

Legal Principles ◽

The North ◽

Legal Problems ◽

The North Sea ◽

The Subject ◽

First Time ◽

Economic Considerations

The possible presence of very large petroleum and natural gas reserves in the area beneath the North Sea is currently the subject of intense investigation. If confirmed, as seems likely in at least some localities, this occurrence will raise legal problems of considerable interest and complexity. For the North Sea is not merely an oilfield covered by water: for centuries it has been one of the world's major fishery regions and the avenue to and from the world's busiest seaports. Thus all three of the present principal uses of the sea—fishing, navigation, and the exploitation of submarine resources—promise to meet for the first time on a large scale in an area where all are of major importance. The process of reconciling the various interests at stake will provide the first thoroughgoing test of the adequacy and acceptability of the general principles laid down in the 1958 Geneva Convention on the Continental Shelf and should add greatly to the practice and precedents available in this developing branch of the law. In the present article an attempt is made to review some of the geographical and economic considerations involved in the North Sea situation, to note some of the technical and legal developments that have already taken place, and to consider these elements in the light of the various interests and legal principles concerned.

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Long-term series in ichthyoplankton: sole and sprat at French coast of the North Sea from 1975 to 1994

Oceanologica Acta ◽

10.1016/s0399-1784(98)80055-8 ◽

1998 ◽

Vol 21 (1) ◽

pp. 113-121 ◽

Cited By ~ 3

Author(s):

Daniel Woehrling ◽

Geneviève Le Fèvre-Lehoërff

Keyword(s):

North Sea ◽

The North ◽

The North Sea

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Inferring the location and scale of mixing between habitat areas of lesser sandeel through information from the fishery

ICES Journal of Marine Science ◽

10.1093/icesjms/fsq154 ◽

2010 ◽

Vol 68 (1) ◽

pp. 43-51 ◽

Cited By ~ 31

Author(s):

Henrik Jensen ◽

Anna Rindorf ◽

Peter J. Wright ◽

Henrik Mosegaard

Keyword(s):

North Sea ◽

Large Scale ◽

Pelagic Fish ◽

Fishing Ground ◽

Marine Science ◽

Foraging Habitat ◽

Small Pelagic Fish ◽

The North ◽

The North Sea

Abstract Jensen, H., Rindorf, A., Wright, P. J., and Mosegaard, H. 2011. Inferring the location and scale of mixing between habitat areas of lesser sandeel through information from the fishery. – ICES Journal of Marine Science, 68: 43–51. Sandeels are small pelagic fish that play an important role in the diet of a range of natural predators. Because of their limited capture by traditional survey gear, little is known about their large-scale distribution or the degree of mixing between habitat areas. Detailed information collected directly from the fishery was used to map fishing grounds, which were then assumed to reflect the foraging habitat of the species. Length distributions from individual hauls were used to assess differences in the distributions as a function of distance between samples. Sandeel foraging habitat covered some 5% of the total area of the North Sea. Mixing between neighbouring fishing grounds was too low to eliminate differences in length distributions at distances between grounds down to 5 km. Within fishing grounds, mixing was sufficient to eliminate differences in length distributions at scales <28 km but insufficient at greater distances. The lack of mixing between grounds may result in large differences in sandeel abundance among adjacent fishing grounds. Further, notable abundance at one end of an extensive fishing ground is not necessarily indicative of similar abundance at its other end.

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