Cargo-Flow-Oriented Design of Supply Vessel Operating in Ice Conditions

2018 ◽  
Author(s):  
Aleksander A. Kondratenko ◽  
Oleg V. Tarovik
Keyword(s):  
Oil And Gas ◽  
Open Water ◽  
Calculation Model ◽  
The Arctic ◽  
Transport Systems ◽  
Detailed Calculation ◽  
Tactical Planning ◽  
Operational Parameters ◽  
Planning Algorithm ◽  
Ice Conditions

Due to the dynamic development of the oil and gas fields in the Arctic, the challenges of supply fleet sizing and composition in this region are becoming relevant. In most studies, the Arctic is mainly associated with ice conditions, but it is not the only factor that influences the design of platform supply vessels (PSV) and corresponding marine transport systems (MTS) for this region. The structure of cargo flow (i.e. its distribution by cargo types) affects the supply system significantly. It defines the level of utilization of vessel capacity that determines transport efficiency. At the same time, the literature represents this aspect poorly. This paper describes an approach to optimize supply fleet configuration by the criterion of total cost considering both non-stationary ice conditions and structure of cargo flows. The cargo-flow-oriented design concept incorporates the detailed calculation model of PSV and the special tactical planning algorithm. PSV model allows considering the influence of cargo spaces on the main characteristics and operational parameters of the ship. It covers the main design aspects of PSVs: general arrangement; lines plan; resistance in open water and ice; engine and propeller characteristics; hydrostatics; capacity and mass calculation. The pseudo-optimal tactical planning algorithm is intended to build the plan of voyages and to set the size of fleet considering the structure of cargo flow. As the test example, we examine a task of servicing the group of platforms in the Kara Sea. The case study shows that cargo flow structure has a high influence on the efficiency of PSVs in case of high-load operation; while a widespread “deck-cargo” approach is unable to consider this aspect because it ignores the vessel’s carrying capacity and payload. The conclusion about a higher efficiency of PSV compared to AHTS with the same displacement was drawn.

Facilitating rain-on-snow detection with satellite data

2021 ◽  
Author(s):  
Annett Bartsch
Keyword(s):  
Satellite Data ◽  
Open Water ◽  
The Arctic ◽  
Calibration And Validation ◽  
In Situ Data ◽  
Snow Properties ◽  
Structure Changes ◽  
Indirect Measures ◽  
Ice Conditions ◽  
Northern European Russia

<p>Rain-on-snow modifies snow properties and can lead to the formation of ice crusts which impact wildlife and also vegetation. Events in the Arctic have been recently linked to specific sea ice conditions (longer open water season) for Siberia. Specifically microwave satellite data have been shown applicable for identification of such events across the Arctic. Related snow structure changes can be observed specifically over Scandinavia, northern European Russia and Western Siberia as well as Alaska (Bartsch, 2010). Events which had severe impacts for reindeer herder herding have occurred several times in the last two decades.</p><p>Challenges further include the categorization of severity of events and attribution of observations to rain-on-snow events.</p><p>Calibration and validation of detection schemes have been largely based on indirect measures. Usually a combination of air temperature and snow height measurements, supported by reports of such events are analysed.</p><p>In this presentation, the utility of current calibration and validation approaches are discussed. Requirements towards in situ data from the viewpoint of satellite based retrievals are outlined.</p><p>Bartsch, A. Ten Years of SeaWinds on QuikSCAT for Snow Applications. Remote Sens. 2010, 2, 1142-1156.</p>

scholarly journals Ice Conditions of an Arctic Polynya: North Water in Winter

1986 ◽  
Vol 32 (112) ◽  
pp. 383-390 ◽  
Author(s):  
Konrad Steffen
Keyword(s):  
Sea Water ◽  
Surface Condition ◽  
Open Water ◽  
Sea Surface ◽  
Aerial Images ◽  
The Arctic ◽  
The North ◽  
North Water ◽  
Ice Conditions ◽  
Fast Ice

AbstractThe surface condition of the North Water was investigated during two winters (i.e. the three polynyas: Smith Sound polynya, Lady Ann Strait polynya, and Barrow Strait polynya). Since no detailed information was available on ice conditions and the extent of open water during winter, radiometric temperature measurements of the sea surface had to be taken along a flight line of 2650 km from an altitude of 300 m. From November to March 1978-79 and 1980-81, 14 remote-sensing flights were carried out. On the basis of the radiometric measurements, the following ice types were identified: ice-free, dark nilas, light nilas, grey ice, grey-white ice, and white ice. A comparison between the thermal and the visual ice classification (the latter being based on grey tones of the aerial images) showed a deviation of 3%. The analysis showed that in November, December, and January more than 50% of the Smith Sound polynya was covered by young ice, nilas, and ice-free, whereas in February and March white ice was dominant. Moreover, it was found that the two polynyas in Smith Sound and Lady Ann Strait were much smaller than previously believed. In Barrow Strait, a semi-permanent polynya was observed in the winter of 1980-81. The occurrence of polynyas in Barrow Strait seems to be connected with the location of the fast-ice edge. On the basis of the calculated ice-type distribution and heat-flux rates for different ice types, an energy loss of 178 W m-2was found on the surface of the Smith Sound polynya due to open water and thin ice for the winter months November to March. Compared with other ice-covered sea surfaces in the Arctic, the heat release by the sea-water in the Smith Sound polynya is about 100 W m-2larger.

Design of Hydrostatically Supported Sand Islands for Arctic Drilling

1980 ◽  
Vol 102 (1) ◽  
pp. 49-54
Author(s):  
B. E. W. Dowse
Keyword(s):  
Oil And Gas ◽  
Water Pressure ◽  
Open Water ◽  
The Arctic ◽  
Paper Briefly ◽  
Construction Technique ◽  
Vertical Side ◽  
Exploration Drilling ◽  
Water Depths ◽  
Permanent Production

The search for oil and gas has already extended to the Arctic areas of the world. To date conventional sand islands have been used for exploration drilling purposes in water depths of up to 43 ft. In deeper water exploration has only been possible using floating drilling equipment which can only operate during the short summer season of open water. This paper briefly outlines the geotechnical principles and development to date of hydrostatically supported sand islands. This construction technique, which utilizes hydrostatic water pressure to stabilize dredged sand at near vertical underwater slopes, would allow sand islands to be quickly and economically built in water depths of up to 200 ft. The hydrostatically supported sand island is a gravity structure and, therefore, is only suitable for use on competent seabed soils. This paper presents two different designs which are currently proposed for use as drilling structures in such areas as the Beaufort Sea. One design is intended for use as a movable exploration structure and the second for a permanent production island that would remain on location for 30 to 50 yr. The near vertical side slopes of the hydrostatically supported sand islands reduce the amount of sand required to manageable amounts, and allow the construction on location to be safely completed during the short Arctic summers. The sand provides sufficient mass to resist ice pressures.

Double Acting Tanker: Experiences from Model Tests and Sea Trials

2005 ◽  
Vol 219 (3) ◽  
pp. 109-119 ◽  
Author(s):  
P Trägärdh ◽  
P Lindell ◽  
N Sasaki
Keyword(s):  
Model Test ◽  
Oil And Gas ◽  
Single Point ◽  
Open Water ◽  
Model Tests ◽  
Water Model ◽  
Research Centre ◽  
Sea Trial ◽  
Cavitation Performance ◽  
Ice Conditions

The acronym DAT stands for double acting tanker, a concept where the ship is designed to run astern in heavy ice conditions while remaining hydrodynamically efficient for ahead propulsion in open water conditions. Two large aframax DATs - 106.000 dwt (deadweight tons) each - have been delivered by Sumitomo Heavy Industries to Fortum Oil and Gas OY. They are the first crude carriers built according to the DAT principle and also the first using pod propulsion from the beginning (Fig. 1). They will also be the world's largest crude carriers with ice class 1A super and are primarily intended for year-round transportation of North Sea crude to Fortum's refineries in the Gulf of Finland. The ships were appointed ‘ship of the year’ in Japan in 2003. SSPA was contracted by Sumitomo Heavy Industries to perform model tests. A comprehensive open water model test programme was used to investigate aspects of resistance and propulsion, manoeuvring, and cavitation performance. As the ship is designed to operate both in ahead and astern conditions for prolonged periods of time, most tests were performed both ahead and astern. Also, a simulation study of dynamic positioning at buoy or floating production, storage offshore (FPSO) loading was made by SSPA. Comprehensive tests of the ship's performance in ice were performed in the ice tank at MARC (Masa-Yards Artic Research Centre). The eight-month model testing and development campaign resulted in a ship with excellent propulsion and manoeuvring performance, especially with regard to the high ice class. Sea trials carried out with ship in August 2002 confirmed the results of the model test. Interesting experiences of the model test campaign and comparison between model test and sea trial results are presented, as well as some examples of single-point mooring simulations.

scholarly journals EXPLORATION WELLS COMPLETION IN ICE CONDITIONS OF THE ARCTIC

2016 ◽  
pp. 61-66
Author(s):  
D. A. Kustyshev ◽  
A. V. Kustyshev ◽  
A. A. Barkov ◽  
M. D. Antonov ◽  
V. A. Dolgushin
Keyword(s):  
Oil And Gas ◽  
Gas Condensate ◽  
The Arctic ◽  
History Of Development ◽  
Oil And Gas Resources ◽  
History Of ◽  
Ice Conditions

The article considers the history of development of oil and gas resources of seas and oceans, and prospects of the Arctic off-shore fields development. The analysis of the project solutions on development of the off-shore gas and gas-condensate fields in the Tyumen region north has been carried out. The technology solutions are proposed aimed on completion of prospecting wells from the ice islands at time deficit using drill rigs, as well as on completion of wells with using the preventing units.

Assessment of the Feasibility of the Arctic Sea Transportation by Using Ship Ice Transit Simulation

2014 ◽  
Author(s):  
Janne Valkonen ◽  
Kaj Riska
Keyword(s):  
Transit Time ◽  
Open Water ◽  
Economic Feasibility ◽  
The Arctic ◽  
Shipping Industry ◽  
Arctic Sea ◽  
Sea Transportation ◽  
Ice Conditions ◽  
Simulation Results ◽  
Ship Performance

Arctic sea transportation has drawn a lot of attention in the recent years. The possibility of using a shorter route between Europe and Asia interests many actors in the shipping industry. Benefits from the shorter route may, at first, seem attractive. However, there might be factors affecting the feasibility of the route that are not obvious at first. The estimated transit speed along the Arctic route is not necessarily reached due to ice and other prevailing conditions. Simplified methods can underestimate the actual transit time, so the use of advanced methods is advisable. A thorough assessment of ship performance along the selected route can reveal factors that affect the feasibility of trans-Arctic shipping. This paper presents how the ship transit along an Arctic route can be simulated and how the ship performance can be assessed based on the simulation results. In this paper comparative results of ship performance in different ice conditions are shown and the benefits and challenges of the ship ice transit simulations are discussed. The effect of the input ice conditions to the ship performance estimates and how the ice information from various sources can be used for the simulations are discussed. Ship performance in the Arctic transit is tested using a probabilistic model called COSSARC for ship performance simulation in ice and open water. The tool can be used for assessing the economic feasibility of ship designs and transport concepts. One of the main benefits of the ship ice transit simulations compared to the simpler methods is that ice ridges are described in the realization of ice conditions statistically and the ship performance in ridges is modeled. A ship might get stuck in ridges and might be forced to wait for assistance from an icebreaker, or a double acting ship might travel slower than anticipated through ridge fields. This increases the transit time significantly, which is not necessarily revealed by simpler methods. The main outcome from the ship ice transit simulations described in this paper, is a more realistic estimate of transit time for a given route. This can be used as input for economic or other assessments. It is possible to estimate the probability of getting stuck in ice ridges from the ship ice transit simulation results, and thus the need for icebreaker assistance can be assessed. The probabilistic simulation of ship performance can be done in the design phase of the ship to assess various design concepts or while selecting what kind of ship or fleet of ships is the most suitable for the given transport task.

scholarly journals Profiling Sea Ice with a Multiple Altimeter Beam Experimental Lidar (MABEL)

2014 ◽  
Vol 31 (5) ◽  
pp. 1151-1168 ◽  
Author(s):  
R. Kwok ◽  
T. Markus ◽  
J. Morison ◽  
S. P. Palm ◽  
T. A. Neumann ◽  
...  
Keyword(s):  
Sea Ice ◽  
Open Water ◽  
Laser Pulses ◽  
The Arctic ◽  
Ice Cloud ◽  
Ice Conditions ◽  
Arctic Coast ◽  
Background Photon ◽  
532 Nm

AbstractThe sole instrument on the upcoming Ice, Cloud, and Land Elevation Satellite (ICESat-2) altimetry mission is a micropulse lidar that measures the time of flight of individual photons from laser pulses transmitted at 532 nm. Prior to launch, the Multiple Altimeter Beam Experimental Lidar (MABEL) serves as an airborne implementation for testing and development. This paper provides a first examination of MABEL data acquired on two flights over sea ice in April 2012: one north of the Arctic coast of Greenland and the other in the east Greenland Sea. The phenomenology of photon distributions in the sea ice returns is investigated. An approach to locate the surface and estimate its elevation in the distributions is described, and its achievable precision is assessed. Retrieved surface elevations over relatively flat leads in the ice cover suggest that precisions of several centimeters are attainable. Restricting the width of the elevation window used in the surface analysis can mitigate potential biases in the elevation estimates due to subsurface returns at 532 nm. Comparisons of nearly coincident elevation profiles from MABEL with those acquired by an analog lidar show good agreement. Discrimination of ice and open water, a crucial step in the determination of sea ice freeboard and the estimation of ice thickness, is facilitated by contrasts in the observed signal–background photon statistics. Future flight paths will sample a broader range of seasonal ice conditions for further evaluation of the year-round profiling capabilities and limitations of the MABEL instrument.

The work of networks: Embedding firms, transport, and the state in the Russian Arctic oil and gas sector

2015 ◽  
Vol 48 (3) ◽  
pp. 558-576 ◽  
Author(s):  
Scott R Stephenson ◽  
John A Agnew
Keyword(s):  
Oil And Gas ◽  
Physical Geography ◽  
The State ◽  
The Arctic ◽  
Transport Systems ◽  
Russian Arctic ◽  
Production Network ◽  
Political Actors ◽  
Oil And Gas Sector ◽  
Arctic Russia

The “network” has gained widespread acceptance within economic geography as a metaphor for economic interaction. Consistent with a global production network (GPN) approach, extractive industries are deeply embedded in political structures, physical infrastructure, and environmental conditions. We advocate for a GPN framework that emphasizes the co-operation of multiple, differentiated networks at each stage of a production network. Furthermore, the physical geography of sub-national spaces as well as trans-national spaces linking resources with destination markets imposes critical constraints on the structure and operation of oil and natural-gas extraction. We attempt to move beyond notions of a singular network encompassing all aspects of production by contextualizing extractive activities within the geopolitical economy of Arctic Russia. Our aim is twofold: to develop a more carefully articulated conception of networks based on the different economic principles and political regulation at work within different types of networks, and to show how the Russian Arctic oil and gas sector can only be adequately understood with such a nuanced approach. The Arctic case illustrates well the complex entanglement of the state and political actors in networks of firms and specialized transport systems. We first deconstruct the network concept to establish the economic principles, actors, and spaces that comprise the extractive production network, and then examine the extractive hydrocarbon networks active in Arctic Russia through this analytical lens.

scholarly journals Ice Conditions of an Arctic Polynya: North Water in Winter

1986 ◽  
Vol 32 (112) ◽  
pp. 383-390 ◽  
Author(s):  
Konrad Steffen
Keyword(s):  
Sea Water ◽  
Surface Condition ◽  
Open Water ◽  
Sea Surface ◽  
Aerial Images ◽  
The Arctic ◽  
The North ◽  
North Water ◽  
Ice Conditions ◽  
Fast Ice

AbstractThe surface condition of the North Water was investigated during two winters (i.e. the three polynyas: Smith Sound polynya, Lady Ann Strait polynya, and Barrow Strait polynya). Since no detailed information was available on ice conditions and the extent of open water during winter, radiometric temperature measurements of the sea surface had to be taken along a flight line of 2650 km from an altitude of 300 m. From November to March 1978-79 and 1980-81, 14 remote-sensing flights were carried out. On the basis of the radiometric measurements, the following ice types were identified: ice-free, dark nilas, light nilas, grey ice, grey-white ice, and white ice. A comparison between the thermal and the visual ice classification (the latter being based on grey tones of the aerial images) showed a deviation of 3%. The analysis showed that in November, December, and January more than 50% of the Smith Sound polynya was covered by young ice, nilas, and ice-free, whereas in February and March white ice was dominant. Moreover, it was found that the two polynyas in Smith Sound and Lady Ann Strait were much smaller than previously believed. In Barrow Strait, a semi-permanent polynya was observed in the winter of 1980-81. The occurrence of polynyas in Barrow Strait seems to be connected with the location of the fast-ice edge. On the basis of the calculated ice-type distribution and heat-flux rates for different ice types, an energy loss of 178 W m-2 was found on the surface of the Smith Sound polynya due to open water and thin ice for the winter months November to March. Compared with other ice-covered sea surfaces in the Arctic, the heat release by the sea-water in the Smith Sound polynya is about 100 W m-2 larger.

Arctic sea ice extent and thickness

1995 ◽  
Vol 352 (1699) ◽  
pp. 301-319 ◽  
Keyword(s):  
Sea Ice ◽  
Open Water ◽  
Arctic Sea Ice ◽  
The Arctic ◽  
Ice Thickness ◽  
Sea Ice Extent ◽  
Arctic Sea ◽  
Ice Conditions ◽  
Fast Ice ◽  
Arctic Sea Ice Extent

Current knowledge on Arctic sea ice extent and thickness variability is reviewed, and we examine whether measurements to date provide evidence for the impact of climate change. The total Arctic ice extent has shown a small but significant reduction of (2.1 ± 0.9)% during the period 1978-87, after apparently increasing from a lower level in the early 1970s. However, open water within the pack ice limit has also diminished, so that the reduction of sea ice area is only (1.8 ± 1.2)%. This stability conceals large interannual variations and trends in individual regions of the Arctic Ocean and sub-Arctic seas, which are out of phase with one another and so have little net impact on the overall hemispheric ice extent. The maximum annual global extent (occurring during the Antarctic winter) shows a more significant decrease of 5% during 1972-87. Ice thickness distribution has been measured by submarine sonar profiling, moored upward sonars, airborne laser prohlometry, airborne electromagnetic techniques and drilling. Promising new techniques include: sonar mounted on an AUV or neutrally buoyant float; acoustic tomography or thermometry; and inference from a combination of microwave sensors. In relation to climate change, the most useful measurement has been repeated submarine sonar profiling under identical parts of the Arctic, which offers some evidence of a decline in mean ice thickness in the 1980s compared to the 1970s. The link between mean ice thickness and climatic warming is complex because of the effects of dynamics and deformation. Only fast ice responds primarily to air temperature changes and one can predict thinning of fast ice and extension of the open water season in fast ice areas. Another region of increasingly mild ice conditions is the central Greenland Sea where winter thermohaline convection is triggered by cyclic growth and melt of local young ice. In recent years convection to the bottom has slowed or ceased, possibly related to moderation of ice conditions.

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