The improved representation of underwater radiances and its impact on simulated physics and biogeochemistry in the North Sea

Author(s):  
Jozef Skakala ◽  
Jorn Bruggeman ◽  
David Ford ◽  
Stefano Ciavatta

<p>In the presented work we advanced our modelling of in-water optics on the North-West European (NWE) Shelf, with important implications for how we model stratification of the water column, primary productivity, and the underwater radiances. We implement a stand-alone bio-optical module into the existing coupled physical-biogeochemical model configuration. The advantage of the bio-optical module, when compared to the pre-existing light scheme is that it resolves the underwater irradiance spectrally and distinguishes between direct and diffuse downwelling streams. The changed underwater irradiance compares better with both satellite and in-situ observations. We show that both underwater irradiance and model biogeochemistry can be further improved by assimilating suitable ocean-color derived satellite products into the model. We use the light module to introduce feedback from biogeochemistry to physics and demonstrate that the two-way coupled model tends to outperform the one-way coupled model in both physics and biogeochemistry. We discuss the implications of our developments for future modelling of the NWE Shelf.</p>

2015 ◽  
Vol 8 (7) ◽  
pp. 5577-5618 ◽  
Author(s):  
J. A. Beecham ◽  
J. Bruggeman ◽  
J. Aldridge ◽  
S. Mackinson

Abstract. End to end modelling is an attractive and rapidly developing approach to solve developing strategies in marine systems science and management. However problems remain in the area of data matching and sub-model compatibility. A mechanism and novel interfacing system (Couplerlib) is presented whereby a physical/biogeochemical model (GOTM-ERSEM) that predicts dynamics of the lower trophic level (LTL) organisms in marine ecosystems is coupled to a dynamic ecosystem model (Ecosim) that predicts food-web interactions among higher trophic level (HTL) organisms. Coupling is achieved by means of a bespoke interface which handles the system incompatibilities between the models and a more generic Couplerlib library which uses metadata descriptions in extensible mark-up language (XML) to marshal data between groups, paying attention to functional group mappings and compatibility of units between models. In addition, within Couplerlib, models can be coupled across networks by means of socket mechanisms. As a demonstration of this approach, a food web model (Ecopath with Ecosim, EwE) and a physical/biogeochemical model (GOTM-ERSEM) representing the North Sea ecosystem were joined with Couplerlib. The output from GOTM-ERSEM varies between years dependent on oceanographic and meteorological conditions. Although inter-annual variability was clearly present, there was always the tendency for an annual cycle consisting of a peak of diatoms in spring, followed by (less nutritious) flagellates and dinoflagellates through the summer resulting in an early summer peak in the mesozooplankton biomass. Pelagic productivity, predicted by the LTL model, was highly seasonal with little winter food for the higher trophic levels. The Ecosim model was originally based on the assumption of constant annual inputs and, consequently, when coupled, pelagic species suffered population loss over the winter months. By contrast, benthic populations were more stable (although the benthic linkage modelled was purely at the detritus level). The coupled model was used to examine long term effects of environmental change, and showed the system to be nutrient limited, relatively unaffected by forecast climate change, especially in the benthos. The stability of an Ecosim formulation for large higher tropic level food webs is discussed and it is concluded that this kind of coupled model formulation is better for examining the effects of long term environmental change than short term perturbations.


2013 ◽  
Vol 29 (1) ◽  
pp. 35-47
Author(s):  
Claire Warden

The multi-spatial landscape of the North-West of England (Manchester–Salford and the surrounding area) provides the setting for Walter Greenwood's 1934 play Love on the Dole. Both the urban industrialized cityscape and the rural countryside that surrounds it are vital framing devices for the narrative – these spaces not simply acting as backdrops but taking on character roles. In this article Claire Warden reads the play's presentation of the North through the concept of landscape theatre, on the one hand, and Raymond Williams's city–country dialogism on the other, claiming that Love on the Dole is imbued with the revolutionary possibility that defines the very landscape in which it is set. From claustrophobic working-class kitchen to the open fields of Derbyshire, Love on the Dole has a sense of spatial ambition in which Greenwood regards all landscapes as tainted by the industrial world while maintaining their capacity to function independently. Ugliness and beauty, capitalist hegemony and socialistic hopefulness reside simultaneously in this important under-researched example of twentieth-century British theatre, thereby reflecting the ambivalent, shifting landscape of the North and producing a play that cannot be easily defined artistically or politically. Claire Warden is a Lecturer in Drama at the University of Lincoln. Her work focuses on peripheral British performances in the early to mid-twentieth century. She is the author of British Avant-Garde Theatre (Palgrave MacMillan, 2012) and is currently writing Modernist and Avant-Garde Performance: an Introduction for Edinburgh University Press, to be published in 2014.


Author(s):  
K. Darkenov ◽  
◽  
K. Kakar ◽  

Central Asia is the heart of the Eurasian continent, a region directly adjacent to China, and the Silk Road, which connects the Eurasian continent, passes through this region. Kazakhstan is a country rich in natural resources and energy in Central Asia. Apart from the mineral resources of Central Asia, its location as the center of two continents, its importance in China's foreign trade and its strategic position in the defense of the North-West Frontier, made Kazakhstan known to the world about the location of this project. Since 2014, China has focused on the "One Belt - One Road" strategy in the region. Since 2014, economic relations between the two countries have developed under the "One Belt - One Road" initiative, but the problems remain. The article is devoted to the analysis of economic relations between the two countries and give some suggestions to solve the problem


Author(s):  
Apolline ALFSEN ◽  
Mark BOSSELAERS ◽  
Olivier LAMBERT

In spite of a continuously expanding physeteroid fossil record, our understanding of the origin and early radiation of the two modern sperm whale families Kogiidae Gill, 1871 (including the pygmy and dwarf sperm whales, Kogia spp.) and Physeteridae Gray, 1821 (including the great sperm whale, Physeter Linnaeus, 1758) remains limited, especially due to the poorly resolved phylogenetic relationships of a number of extinct species. Among those, based on fragmentary cranial material from the late early to middle Miocene of Antwerp (Belgium, North Sea basin), the small-sized Thalassocetus antwerpiensis Abel, 1905 has been recognized for some time as the earliest branching kogiid. The discovery of a new diminutive physeteroid cranium from the late Miocene (Tortonian) of Antwerp leads to the description and comparison of a close relative of T. antwerpiensis. Thanks to the relatively young ontogenetic stage of this new specimen, the highly modified plate-like bones making the floor of its supracranial basin could be individually removed, a fact that greatly helped deciphering their identity and geometry. Close morphological similarities with T. antwerpiensis allow for the reassessment of several facial structures in the latter; the most important reinterpretation is the one of a crest-like structure, previously identified as a sagittal facial crest, typical for kogiids, and here revised as the left posterolateral wall of the supracranial basin, comprised of the left nasal (lost in kogiids for which the postnarial region is known) and the left maxilla. Implemented in a phylogenetic analysis, the new anatomical interpretations result in the new Belgian specimen and T. antwerpiensis being recovered as sister-groups in the family Physeteridae. Consequently, the geologically oldest kogiids are now dated from the Tortonian, further extending the ghost lineage separating these early late Miocene kogiid records from the estimated latest Oligocene to earliest Miocene divergence of kogiids and physeterids.


Author(s):  
Anne Haour

This chapter explains the coverage of this book, which is about the comparison of rulers, warriors, traders, and clerics on the central Sahel and the North Sea region. It argues that there was more similarity between north-western Europe and the central Sahel in the few centuries either side of AD 1001 than has hitherto been recognised, and maintains that the nature of the sources has obscured these formative times and left them in the shadow of organised structures. It discusses the interconnectedness of central Sahel and north-west Europe through contacts and shared pre-industrial nature.


Atmosphere ◽  
2019 ◽  
Vol 10 (5) ◽  
pp. 272 ◽  
Author(s):  
Christian Dieterich ◽  
Shiyu Wang ◽  
Semjon Schimanke ◽  
Matthias Gröger ◽  
Birgit Klein ◽  
...  

An ensemble of regional climate change scenarios for the North Sea is validated and analyzed. Five Coupled Model Intercomparison Project Phase 5 (CMIP5) General Circulation Models (GCMs) using three different Representative Concentration Pathways (RCPs) have been downscaled with the coupled atmosphere–ice–ocean model RCA4-NEMO. Validation of sea surface temperature (SST) against different datasets suggests that the model results are well within the spread of observational datasets. The ensemble mean SST with a bias of less than 1 ∘ C is the solution that fits the observations best and underlines the importance of ensemble modeling. The exchange of momentum, heat, and freshwater between atmosphere and ocean in the regional, coupled model compares well with available datasets. The climatological seasonal cycles of these fluxes are within the 95% confidence limits of the datasets. Towards the end of the 21st century the projected North Sea SST increases by 1.5 ∘ C (RCP 2.6), 2 ∘ C (RCP 4.5), and 4 ∘ C (RCP 8.5), respectively. Under this change the North Sea develops a specific pattern of the climate change signal for the air–sea temperature difference and latent heat flux in the RCP 4.5 and 8.5 scenarios. In the RCP 8.5 scenario the amplitude of the spatial heat flux anomaly increases to 5 W/m 2 at the end of the century. Different hypotheses are discussed that could contribute to the spatially non-uniform change in air–sea interaction. The most likely cause for an increased latent heat loss in the central western North Sea is a drier atmosphere towards the end of the century. Drier air in the lee of the British Isles affects the balance of the surface heat budget of the North Sea. This effect is an example of how regional characteristics modulate global climate change. For climate change projections on regional scales it is important to resolve processes and feedbacks at regional scales.


1977 ◽  
Vol 1977 (1) ◽  
pp. 45-52 ◽  
Author(s):  
D. R. Blaikley ◽  
G. F. L. Dietzel ◽  
A. W. Glass ◽  
P. J. van Kleef

ABSTRACT The reasons are introduced for the development of a simulator sufficiently simple to enable weather data normally acquired for E & P operations to be used. “SLIKTRAK,” developed by Shell, applies a slick description and combat concept, developed within the E & P Forum for well blowouts in the North Sea, but applicable to other areas. This concept includes costs for cleanup, damages and the effect of phenomena such as evaporation and natural dispersion. These factors are based on industry experience and vary primarily with sea conditions. The computer programme simulates the continued creation of an oil spill and applies weather data to predict movements of each day's spillage for successive days at sea and quantities of oil left after each day until the oil either disappears or reaches a coastline. Cumulative probability curves for the oil volumes cleaned up, oil arriving at specified shores, total costs, etc., are produced by random selection of input variables such as well location, weather data, the possibility of well bridging etc., and repetition of simulated spill incidents over a large number of cycles. Trace-plots of individual spills may also be generated. In association with the E & P Forum's position as technical advisers to the North West European Civil Liability Convention for Oil Pollution Damage from Offshore Operations, a study based on the North Sea areas has been made. These results and further developments of the program are discussed.


Africa ◽  
2006 ◽  
Vol 76 (2) ◽  
pp. 180-199 ◽  
Author(s):  
Mark Leopold

AbstractThis article outlines the history of a people known as ‘Nubi’ or ‘Nubians’, northern Ugandan Muslims who were closely associated with Idi Amin's rule, and a group to which he himself belonged. They were supposed to be the descendants of former slave soldiers from southern Sudan, who in the late 1880s at the time of the Mahdi's Islamic uprising came into what is now Uganda under the command of a German officer named Emin Pasha. In reality, the identity became an elective one, open to Muslim males from the northern Uganda/southern Sudan borderlands, as well as descendants of the original soldiers. These soldiers, taken on by Frederick Lugard of the Imperial British East Africa Company, formed the core of the forces used to carve out much of Britain's East African Empire. From the days of Emin Pasha to those of Idi Amin, some Nubi men were identified by a marking of three vertical lines on the face – the ‘One-Elevens’. Although since Amin's overthrow many Muslims from the north of the country prefer to identify themselves as members of local Ugandan ethnic groups rather than as ‘Nubis’, aspects of Nubi identity live on among Ugandan rebel groups, as well as in cyberspace.


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