Definition of Efficiency and Safety Criteria for Icebreaker in Ice Management Operations

Author(s):  
Evgeny Karulin ◽  
Marina Karulina ◽  
Mikhail Kazantsev ◽  
Aleksander Proniashkin ◽  
Dmitry Zaikin

Ice management (IM) is often required to support offshore production of oil and gas in freezing seas. It helps to mitigate ice impact on marine structures and thus minimize risks of accidents as well as to increase weather windows for marine operations. One of the IM tactics is to use an icebreaker for producing a zone of managed ice for ensuring safe and efficient operation of marine facilities: platforms, offloading terminals, tankers, etc. The choice of the right icebreaker which is best capable to cope with the IM jobs is quite a challenging task. This paper suggests an approach to objectively compare operational efficiency of different icebreakers in performance of some typical IM tasks. This approach made it possible to work out universal criteria for assessing the efficiency of these ships. The criteria of icebreaker efficiency and operational performance have been derived from actual ice breaking and maneuvering data including safety aspects of required icebreaker maneuvers. The paper contains case studies with estimation of the said criteria for a number of IM icebreakers expected to be used for ice management in the south-eastern part of the Barents Sea.

Author(s):  
I. G. Mindel ◽  
B. A. Trifonov ◽  
M. D. Kaurkin ◽  
V. V. Nesynov

In recent years, in connection with the national task of developing the Arctic territories of Russia and the perspective increase in the hydrocarbon mining on the Arctic shelf, more attention is being paid to the study of seismicity in the Barents Sea shelf. The development of the Russian Arctic shelf with the prospect of increasing hydrocarbon mining is a strategically important issue. Research by B.A. Assinovskaya (1990, 1994) and Ya.V. Konechnaya (2015) allowed the authors to estimate the seismic effects for the northern part of the Barents Sea shelf (Novaya Zemlya region). The paper presents the assessment results of the initial seismic impacts that can be used to solve seismic microzoning problems in the areas of oil and gas infrastructure during the economic development of the Arctic territory.


Author(s):  
Adekunle Peter Orimolade ◽  
Ove Tobias Gudmestad

Interests in exploration and production of oil and gas in cold climate areas has increased in recent times. This can be attributed to the continual depletion of reserves in mature fields, and recent discoveries of large quantities of oil and gas in the cold climate region, including the more recent discovery of the Alta Reservoir, in the Barents Sea. However, marine operations in this region are faced with challenges resulting from its arctic conditions. Knowledge of the physical environment is important in designing offshore structures, and in planning, and executing marine operations. Selection of a suitable field development concept may be influenced by the probability of occurrence of rare events, such as drifting icebergs. Furthermore, occurrence of mesoscale phenomenon such as polar low pressures may adversely affect planned marine operations. In addition, uncertainties in weather forecasting will reflect on the available weather window to perform installation and interventions works. This paper presents some of the challenges in designing and planning for marine operations in the cold climate region. A possible field development concept for the open water areas of the Norwegian sector of the Barents Sea is discussed. The current research work considers the need for further assessment of the probability of occurrence of drifting icebergs as of importance when selecting field development concept. The Floating Production Storage and Offloading (FPSO) is proposed, and this should be designed with an internal turret system that can be disconnected and reconnected. Some of the challenges associated with riser systems design when considering a turret system with the capability to disconnect and reconnect are discussed. This paper also propose the use of ensemble forecasts as an alternative to the use of alpha factors to estimate operational weather window when planning for marine operations in the Barents Sea. The unpredictability nature of the environmental conditions, especially in the early winter is considered a challenge to marine operations.


2004 ◽  
Vol 19 (2) ◽  
pp. 158-163 ◽  
Author(s):  
Rolf Haagensen ◽  
Karl-Åke Sjøborg ◽  
Anders Rossing ◽  
Henry Ingilæ ◽  
Lars Markengbakken ◽  
...  

AbstractBackground:Search and rescue helicopters from the Royal Norwegian Air Force conduct ambulance and search and rescue missions in the Barents Sea. The team on-board includes an anesthesiologist and a paramedic. Operations in this area are challenging due to long distances, severe weather conditions, and arctic winter darkness.Methods:One-hundred, forty-seven ambulance and 29 search and rescue missions in the Barents Sea during 1994–1999 were studied retrospectively with special emphasis on operative conditions and medical results.Results and Discussion:Thirty-five percent of the missions were carried out in darkness. The median time from the alarm to first patient contact was 3.3 hours and the median duration of the missions was 7.3 hours. Forty-eight percent of the missions involved ships of foreign origin. Half the patients had acute illnesses, dominated by gastrointestinal and heart diseases. Most of the injuries resulted from industrial accidents with open and closed fractures, amputations, and soft tissue damage. Ninety percent of the patients were hospitalized; 7.5% probably would not have survived without early medical treatment and rapid transportation to a hospital.Conclusion:Using a heavy search and rescue helicopter in the Barents Sea was the right decision in terms of medical gain and operative risk.


2007 ◽  
Vol 4 (6) ◽  
pp. 897-931
Author(s):  
R. C. Levine ◽  
D. J. Webb

Abstract. Following meteorological practice the definition of available potential energy in the ocean is conventionally defined in terms of the properties of the global ocean. However there is also a requirement for a localised definition, for example the energy released when shelf water cascades down a continental shelf in the Arctic and enters a boundary current. In this note we start from first principals to obtain an exact expression for the available energy (AE) in such a situation. We show that the available energy depends on enstrophy and gravity. We also show that it is exactly equal to the work done by the pressure gradient and by buoyancy. The results are used to investigate the distribution of AE in the Barents Sea and surrounding regions relative to the interior of the Arctic Ocean. We find that water entering the Barents Sea from the Atlantic already has a high AE, that it is increased by cooling but that much of the increase is lost overcoming turbulence during the passage through the region to the Arctic Ocean. However on entering the Arctic enough available energy remains to drive a significant current around the margin of the ocean. The core of raised available energy also acts as a tracer which can be followed along the continental slope beyond the dateline.


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