ISSC Technical Committee I.1 Environment

2007 ◽  
Author(s):  
Bruce L. Hutchison
Keyword(s):  
Climate Change ◽  
Marine Environment ◽  
Rogue Waves ◽  
Offshore Structures ◽  
Technical Committee ◽  
Environmental Data ◽  
Offshore Structure ◽  
Parametric Roll ◽  
Modeling And Analysis ◽  
The Past

This paper presents highlights of the report of the 16th International Ship and Offshore Structure Congress (ISSC) I.1 Environment Committee presented in August 2006 in Southampton, UK. Subjects addressed include notable accomplishments in the study of the marine environment pertinent to the design and operation of ships and offshore structures. These include advances in the past three years with respect to sensing, modeling and analysis of environmental data, discussion of rogue waves, climate change and parametric roll, and recommendations for further research.

Verification and calibration studies for the new CAN/CSA-S472 foundations of offshore structures

1993 ◽  
Vol 30 (3) ◽  
pp. 515-525 ◽  
Author(s):  
K. Been ◽  
J.I. Clark ◽  
W.R. Livingstone
Keyword(s):  
Offshore Structures ◽  
Technical Committee ◽  
Performance Standard ◽  
Safety Factors ◽  
Offshore Structure ◽  
Limit States ◽  
Resistance Factors ◽  
Development Of Resistance ◽  
System A ◽  
Load And Resistance Factors

In June 1992, the Canadian Standards Association (CSA) published a code for the design, construction, and installation of fixed offshore structures. This code is relatively advanced in its application of limit states design to offshore structures. The part dealing with foundations is written as a performance standard. It does not specify resistance factors (or safety factors) to achieve the target reliability of the structure. Although limit states design is common practice among geotechnical engineers, the application of resistance factors is a problem. This paper describes some of the studies and conclusions reached by the Technical Committee in the development of the CSA foundations standard. As a first step, resistance factors were developed by calibration to conventional total factors of safety for the failure mechanisms considered. This approach has severe limitations. In particular, the applicability of safety factors developed for onshore practice or other offshore areas to the ice-dominated environment of Canadian offshore regions is questionable. In addition, many offshore structure designs include consideration of dynamic loading and scour or erosion problems that cannot be satisfactorily dealt with using factors of safety. An example of the problem of applying separate load and resistance factors for a bearing-capacity problem is given to show that load and resistance are not independent of each other. Because of the problems with development of resistance factors, the CSA foundations standard dictates that offshore structure designs include a risk analysis of the foundation system. A simple form of such an analysis for a caisson-retained sand structure is included in the paper. Key words : offshore structures, foundations, standard, safety, limit states design.

Potential Changes of the North Atlantic Wind and Wave Climate and Occurrence of Rogue Waves

2016 ◽  
Author(s):  
Elzbieta M. Bitner-Gregersen
Keyword(s):  
Climate Change ◽  
21St Century ◽  
North Atlantic ◽  
Radiative Forcing ◽  
Climate Models ◽  
Rogue Waves ◽  
The Past ◽  
The North ◽  
The North Atlantic ◽  
Wave Conditions

The present study investigates potential changes of wind and wave conditions in one North Atlantic location in the 21st century. The Fifth Assessment Report of the Intergovernmental Panel on Climate Change (IPCC) uses four scenarios for future greenhouse gas concentrations in the atmosphere called Representative Concentration Pathways (RCP). Two of these scenarios with radiative forcing of 4.5 and 8.5 W/m2 by the end of the 21st century have been selected to project wind and wave conditions in the North Atlantic. The third generation (3G) wave model WAM, forced by winds obtained from GFDL-CM3, EC-Earth, HADGEM2, IPS-CM5A-MR, MRI-GCGCM3 and MIROC5 climate models, has been used to project waves for these two scenarios for the historical period 1971–2000 and the future period 2071–2100. Long-term probabilistic description of wind and waves is provided and deviations between the past and future wind and wave conditions are demonstrated, given attention to the projections obtained by use of the GFDL-CM3 and EC-Earth climate models. Changes in extreme wind and waves are shown and uncertainties associated with climate change projections discussed. Occurrence of rogue-prone crossing sea states which may trigger generation of rogue waves in the past and future climate is also investigated.

scholarly journals An Overview of classifications and incidents/accidents in offshore structures: Oil and gas

2020 ◽  
Vol 1 (4) ◽  
pp. 13-18
Author(s):  
Jean Pierre Lukongo Ngenge ◽  
Abdallah M.S. Wafi
Keyword(s):  
Oil And Gas ◽  
Offshore Structures ◽  
Research Topic ◽  
Offshore Platforms ◽  
Offshore Structure ◽  
The Past ◽  
Wide Range ◽  
Advanced Knowledge ◽  
Construction Accidents ◽  
The Impact

Offshore platforms are considered among the most significant structures in the world that humans have ever built, having to function in a wide range of extremely challenging environments and have a major impact on the economy and industrial progress of countries. It is extremely important to properly plan, design, construct, transport and install such offshore structures. In the absence of commitment to this, the consequences could be severe in both economic and environmental terms. An overview of offshore structures is presented in this paper, and its purpose is to offer a consistent vision for the various types of offshore structures to be used for the extraction of oil and gas. In addition, the paper focuses on the expected accidents that may occur during and after construction. Accidents do not only cover the difficult environment where these structures are to be built, but they also cover the impact of climate change on these structures. The approach considered in this paper involves a systematic literature review that deals with reviewing different studies done on the similar research topic. The results found in this study determined that the type of offshore structure to be built or fixed at a particular location in water, depends mainly on the water depth and also on the past and present environmental records. Nonetheless, the outcomes of this study are still general; thus, further studies have to be completed in order to acquire more advanced knowledge in this particular field.

Denouement: World Politics, Systemic Leadership, and Climate Change

2018 ◽  
Author(s):  
William R. Thompson ◽  
Leila Zakhirova
Keyword(s):  
Climate Change ◽  
Global Warming ◽  
World Politics ◽  
First Century ◽  
Modern World ◽  
Climate Fluctuations ◽  
The Past ◽  
Agrarian Economy ◽  
Historical Processes

In this final chapter, we conclude by recapitulating our argument and evidence. One goal of this work has been to improve our understanding of the patterns underlying the evolution of world politics over the past one thousand years. How did we get to where we are now? Where and when did the “modern” world begin? How did we shift from a primarily agrarian economy to a primarily industrial one? How did these changes shape world politics? A related goal was to examine more closely the factors that led to the most serious attempts by states to break free of agrarian constraints. We developed an interactive model of the factors that we thought were most likely to be significant. Finally, a third goal was to examine the linkages between the systemic leadership that emerged from these historical processes and the global warming crisis of the twenty-first century. Climate change means that the traditional energy platforms for system leadership—coal, petroleum, and natural gas—have become counterproductive. The ultimate irony is that we thought that the harnessing of carbon fuels made us invulnerable to climate fluctuations, while the exact opposite turns out to be true. The more carbon fuels are consumed, the greater the damage done to the atmosphere. In many respects, the competition for systemic leadership generated this problem. Yet it is unclear whether systemic leadership will be up to the task of resolving it.

scholarly journals EXTREME WAVE PRESSURES AND LOADS ON A PILE-SUPPORTED WHARF DECK - INFLUENCES OF AIR GAP AND WAVE DIRECTION

2018 ◽  
pp. 5
Author(s):  
Andrew Cornett
Keyword(s):  
Offshore Structures ◽  
Model Tests ◽  
Scale Model ◽  
Extreme Waves ◽  
Wave Direction ◽  
Coastal Structures ◽  
Extreme Wave ◽  
Wave Impact ◽  
The Past ◽  
Water Depths

Many deck-on-pile structures are located in shallow water depths at elevations low enough to be inundated by large waves during intense storms or tsunami. Many researchers have studied wave-in-deck loads over the past decade using a variety of theoretical, experimental, and numerical methods. Wave-in-deck loads on various pile supported coastal structures such as jetties, piers, wharves and bridges have been studied by Tirindelli et al. (2003), Cuomo et al. (2007, 2009), Murali et al. (2009), and Meng et al. (2010). All these authors analyzed data from scale model tests to investigate the pressures and loads on beam and deck elements subject to wave impact under various conditions. Wavein- deck loads on fixed offshore structures have been studied by Murray et al. (1997), Finnigan et al. (1997), Bea et al. (1999, 2001), Baarholm et al. (2004, 2009), and Raaij et al. (2007). These authors have studied both simplified and realistic deck structures using a mixture of theoretical analysis and model tests. Other researchers, including Kendon et al. (2010), Schellin et al. (2009), Lande et al. (2011) and Wemmenhove et al. (2011) have demonstrated that various CFD methods can be used to simulate the interaction of extreme waves with both simple and more realistic deck structures, and predict wave-in-deck pressures and loads.

scholarly journals Ensemble models on palaeoclimate to predict India's groundwater challenge

2013 ◽  
Vol 2 (3) ◽  
Author(s):  
Partha Sarathi Datta
Keyword(s):  
Climate Change ◽  
Climate Models ◽  
Global Climate ◽  
Global Climate Models ◽  
Humid Climate ◽  
Ensemble Models ◽  
North West ◽  
The Past ◽  
The North ◽  
14C Age

In many parts of the world, freshwater crisis is largely due to increasing water consumption and pollution by rapidly growing population and aspirations for economic development, but, ascribed usually to the climate. However, limited understanding and knowledge gaps in the factors controlling climate and uncertainties in the climate models are unable to assess the probable impacts on water availability in tropical regions. In this context, review of ensemble models on δ18O and δD in rainfall and groundwater, 3H- and 14C- ages of groundwater and 14C- age of lakes sediments helped to reconstruct palaeoclimate and long-term recharge in the North-west India; and predict future groundwater challenge. The annual mean temperature trend indicates both warming/cooling in different parts of India in the past and during 1901–2010. Neither the GCMs (Global Climate Models) nor the observational record indicates any significant change/increase in temperature and rainfall over the last century, and climate change during the last 1200 yrs BP. In much of the North-West region, deep groundwater renewal occurred from past humid climate, and shallow groundwater renewal from limited modern recharge over the past decades. To make water management to be more responsive to climate change, the gaps in the science of climate change need to be bridged.

scholarly journals Chlorine-free synthesis: An overview

2012 ◽  
Vol 84 (3) ◽  
pp. 411-423 ◽  
Author(s):  
Pietro Tundo
Keyword(s):  
Climate Change ◽  
Industrial Revolution ◽  
High Energy ◽  
Special Topic ◽  
Ozone Layer Depletion ◽  
The Past ◽  
Process Chemistry ◽  
End Products ◽  
Chemical Strategies ◽  
Topic Issue

Since the Industrial Revolution, chlorine has featured as an iconic molecule in process chemistry even though its production by electrolysis of sodium chloride is very energy-intensive. Owing to its high energy and reactivity, chlorine allows the manufacture of chlorinated derivatives in a very easy way: AlCl3, SnCl4, TiCl4, SiCl4, ZnCl2, PCl3, PCl5, POCl3, COCl2, etc. in turn are pillar intermediates in the production of numerous everyday goods. This kind of chloride chemistry is widely used because the energy is transferred to these intermediates, making further syntheses easy. The environmental and health constraints (toxicity and eco-toxicity, ozone layer depletion) and the growing need for energy (energy efficiency, climate change) force us to take advantage from available knowledge to develop new chemical strategies. Substitution of chlorine in end products in compounds where “chlorine is used in the making” means that we avoid electrolysis as primary energetic source; this makes chemistry “without chlorine” considerably more difficult and illustrates why it has not found favor in the past. The rationale behind this Special Topic issue is to seek useful and industrially relevant examples for alternatives to chlorine in synthesis, so as to facilitate the development of industrially relevant and implementable breakthrough technologies.

Alpine sparsely vegetated areas in the eastern Qilian Mountains shrank with climate warming in the past 30 years

2018 ◽  
Vol 42 (4) ◽  
pp. 415-430 ◽  
Author(s):  
Biao Zeng ◽  
Fuguang Zhang ◽  
Taibao Yang ◽  
Jiaguo Qi ◽  
Mihretab G Ghebrezgabher
Keyword(s):  
Climate Change ◽  
Climate Warming ◽  
Vegetation Index ◽  
Normalized Difference Vegetation Index ◽  
Regional Scale ◽  
Qilian Mountains ◽  
Visual Interpretation ◽  
Hydrothermal Conditions ◽  
The Past ◽  
Distribution Ranges

Alpine sparsely vegetated areas (ASVAs) in mountains are sensitive to climate change and rarely studied. In this study, we focused on the response of ASVA distribution to climate change in the eastern Qilian Mountains (EQLM) from the 1990s to the 2010s. The ASVA distribution ranges in the EQLM during the past three decades were obtained from the Thematic Mapper remote sensing digital images by using the threshold of normalized difference vegetation index (NDVI) and artificial visual interpretation. Results indicated that the ASVA shrank gradually in the EQLM and lost its area by approximately 11.4% from the 1990s to the 2010s. The shrunken ASVA with markedly more area than the expanded one was mainly located at altitudes from 3700 m to 4300 m, which were comparatively lower than the average altitude of the ASVA distribution ranges. This condition led to the low ASVA boundaries in the EQLM moving upwards at a significant velocity of 22 m/decade at the regional scale. This vertical zonal process was modulated by topography-induced differences in local hydrothermal conditions. Thus, the ASVA shrank mainly in its lower parts with mild and sunny slopes. Annual maximum NDVI in the transition zone increased significantly and showed a stronger positive correlation with significantly increasing temperature than insignificant precipitation variations during 1990–2015. The ASVA shrinkage and up-shifting of its boundary were attributed to climate warming, which facilitated the upper part of alpine meadow in the EQLM by releasing the low temperature limitation on vegetation growth.

Climate change features along the Brahmaputra Valley in the past 26 years and possible causes

2010 ◽  
Vol 106 (4) ◽  
pp. 649-660 ◽  
Author(s):  
Minhong Song ◽  
Yaoming Ma ◽  
Yu Zhang ◽  
Maoshan Li ◽  
Weiqiang Ma ◽  
...  
Keyword(s):  
Climate Change ◽  
The Past ◽  
Brahmaputra Valley

Understanding the decay of stone-built cultural heritage

2008 ◽  
Vol 32 (4) ◽  
pp. 439-461 ◽  
Author(s):  
B.J. Smith ◽  
M. Gomez-Heras ◽  
S. McCabe
Keyword(s):  
Climate Change ◽  
Natural Environment ◽  
Management Strategies ◽  
Building Stone ◽  
Stone Decay ◽  
Building Stones ◽  
The Public ◽  
The Past ◽  
Built Heritage ◽  
Common Misconceptions

The problem of the decay and conservation of stone-built heritage is a complex one, requiring input across many disciplines to identify appropriate remedial steps and management strategies. Over the past few decades, earth scientists have brought a unique perspective to this challenging area, drawing on traditions and knowledge obtained from research into landscape development and the natural environment. This paper reviews the crucial themes that have arisen particularly, although not exclusively, from the work of physical geographers — themes that have sought to correct common misconceptions held by the public, as well as those directly engaged in construction and conservation, regarding the nature, causes and controls of building stone decay. It also looks to the future, suggesting how the behaviour of building stones (and hence the work of stone decay scientists) might alter in response to the looming challenge of climate change.

Sign in / Sign up

Export Citation Format

Share Document