Coastal Megacities Research Articles

Megacities and large urban agglomerations in the coastal zone: interactions between atmosphere, land, and marine ecosystems.

Megacities are not only important drivers for socio-economic development but also sources of environmental challenges. Many megacities and large urban agglomerations are located in the coastal zone where land, atmosphere, and ocean meet, posing multiple environmental challenges which we consider here. The atmospheric flow around megacities is complicated by urban heat island effects and topographic flows and sea breezes and influences air pollution and human health. The outflow of polluted air over the ocean perturbs biogeochemical processes. Contaminant inputs can damage downstream coastal zone ecosystem function and resources including fisheries, induce harmful algal blooms and feedback to the atmosphere via marine emissions. The scale of influence of megacities in the coastal zone is hundreds to thousands of kilometers in the atmosphere and tens to hundreds of kilometers in the ocean. We list research needs to further our understanding of coastal megacities with the ultimate aim to improve their environmental management.

Megacities in the coastal zone: Using a driver-pressure-state-impact-response framework to address complex environmental problems

The purpose of this study was to elaborate on the role of coastal megacities in environmental degradation and their contribution to global climate change. Although only less than 4 percent of the total world’s population resides in coastal megacities, their impact on environment is significant due to their rapid development, high population densities and high consumption rate of their residents. This study was carried out by implementing a Drivers-Pressures-States-Impacts-Responses (DPSIR) framework. This analytical framework was chosen because of its potential to link the existing data, gathered from various previous studies, in causal relationship. In this text, coastal megacities have been defined as cities exceeding 10 million inhabitants, situated in "near-coastal zone". Their high rates of the consumption of food, water, space and energy were observed and linked to the high performance rates of related economic activities (industry, transportation, power generation, agriculture and water extraction). In many of the studied coastal megacities, deteriorated quality of air and water was perceived, which can, in combination with global warming, lead to health problems and economic and social disturbance among residents. The extent of problems varied between developing and developed countries, showing higher rates of population growth and certain harmful emissions in megacities of developing countries, as well as more problems regarding food and water shortages, sanitation, and health care support. Although certain projections predict slowdown of growth in most coastal megacities, their future impact on environment is still unclear due to the uncertainties regarding future climate change and trajectories of consumption patterns.

Climate change risk assessment in Asian coastal megacities: Knowledge gaps and research needs for urban development planning

Climate change risk assessment in Asian coastal megacities: Knowledge gaps and research needs for urban development planning

Origin and Extent of Fresh Paleowaters on the Atlantic Continental Shelf, USA

While the existence of relatively fresh groundwater sequestered within permeable, porous sediments beneath the Atlantic continental shelf of North and South America has been known for some time, these waters have never been assessed as a potential resource. This fresh water was likely emplaced during Pleistocene sea-level low stands when the shelf was exposed to meteoric recharge and by elevated recharge in areas overrun by the Laurentide ice sheet at high latitudes. To test this hypothesis, we present results from a high-resolution paleohydrologic model of groundwater flow, heat and solute transport, ice sheet loading, and sea level fluctuations for the continental shelf from New Jersey to Maine over the last 2 million years. Our analysis suggests that the presence of fresh to brackish water within shallow Miocene sands more than 100 km offshore of New Jersey was facilitated by discharge of submarine springs along Baltimore and Hudson Canyons where these shallow aquifers crop out. Recharge rates four times modern levels were computed for portions of New England's continental shelf that were overrun by the Laurentide ice sheet during the last glacial maximum. We estimate the volume of emplaced Pleistocene continental shelf fresh water (less than 1 ppt) to be 1300 km(3) in New England. We also present estimates of continental shelf fresh water resources for the U.S. Atlantic eastern seaboard (10(4) km(3)) and passive margins globally (3 x 10(5) km(3)). The simulation results support the hypothesis that offshore fresh water is a potentially valuable, albeit nonrenewable resource for coastal megacities faced with growing water shortages.

Fermentation in the China Beer Industry

As firms in many industries seek to enter new international markets to sustain their growth, they often find themselves in a strategic quandary. Product designs, marketing approaches, supply-chain management issues, and business strategies designed for one region of the world often require significant time and managerial effort to successfully reconfigure and adapt them to new markets. The evolution of customer demand, preferences, and buying patterns can vary markedly from onemarket to another. In fact, regional markets can exhibit profound differences even within the boundaries of a single nation. For example, in China, the sophisticated urban coastal mega-cities that line the Pacific shores teem with millions of customers willing to pay top dollar for foreignbranded goods. Yet, a few hundred miles inland, there are hundreds of millions of people who have yet to see a foreigner walk through their small city streets. Entry into a large foreign market generates considerable strategic opportunities as well as challenges for both multinational firms and domestic firms. Foreign markets often allow a multinational firm to introduce a new line of products designed specifically for that market, or to modify their existing products to better suit the tastes and needs of the targeted customers. These efforts can take considerable time and effort to yield success. Some firms may seek to establish a presence rapidly in a newmarket so as to capture firstmover advantages; others may move slowly in order to better understand the local subtleties and possible pitfalls of serving customers with very different preferences. Although firms in any given market compete with one another for customers, they paradoxically also become highly interdependent over time—in that they are impacted by a common set of underlying geographical factors and other macro-environmental conditions that shape the economics of competing in a given market. This article examines the fast-evolving competitive dynamics that are now redefining the brewing industry in one of the world’s largest markets—China. By examining the strategic approaches of domestic and multinational firms jockeying for market position in China, managers can better understand and act on some of the emerging Organizational Dynamics, Vol. 35, No. 1, pp. 32–48, 2006 ISSN 0090-2616/$ – see frontmatter 2005 Elsevier Inc. All rights reserved. doi:10.1016/j.orgdyn.2005.12.002 www.organizational-dynamics.com

Management of coastal mega-cities—a new challenge in the 21st century

Abstract This paper aims at addressing the issue of coastal mega-cities as a new challenge in the integrated coastal management in the 21st century. The paper first gives a background introduction to the importance of coastal mega-cities in the ICM. It then summarizes the country practices in the management of coastal mega-cities. The main outcomes of the IOC-SOA international workshop on coastal mega-cities are also provided, including the main contents of the Hangzhou Declaration. In the conclusion, recommendations are made as to how to follow up the issue of coastal mega-cities in the years to come.

Resilience to natural hazards: How useful is this concept?

Abstract Resilience is widely seen as a desirable system property in environmental management. This paper explores the concept of resilience to natural hazards, using weather-related hazards in coastal megacities as an example. The paper draws on the wide literature on megacities, coastal hazards, hazard risk reduction strategies, and resilience within environmental management. Some analysts define resilience as a system attribute, whilst others use it as an umbrella concept for a range of system attributes deemed desirable. These umbrella concepts have not been made operational to support planning or management. It is recommended that resilience only be used in a restricted sense to describe specific system attributes concerning (i) the amount of disturbance a system can absorb and still remain within the same state or domain of attraction and (ii) the degree to which the system is capable of self-organisation. The concept of adaptive capacity, which has emerged in the context of climate change, can then be adopted as the umbrella concept, where resilience will be one factor influencing adaptive capacity. This improvement to conceptual clarity would foster much-needed communication between the natural hazards and the climate change communities and, more importantly, offers greater potential in application, especially when attempting to move away from disaster recovery to hazard prediction, disaster prevention, and preparedness.

Resilience to natural hazards: How useful is this concept?

Resilience is widely seen as a desirable system property in environmental management. This paper explores the concept of resilience to natural hazards, using weather-related hazards in coastal megacities as an example. The paper draws on the wide literature on megacities, coastal hazards, hazard risk reduction strategies, and resilience within environmental management. Some analysts define resilience as a system attribute, whilst others use it as an umbrella concept for a range of system attributes deemed desirable. These umbrella concepts have not been made operational to support planning or management. It is recommended that resilience only be used in a restricted sense to describe specific system attributes concerning (i) the amount of disturbance a system can absorb and still remain within the same state or domain of attraction and (ii) the degree to which the system is capable of self-organisation. The concept of adaptive capacity, which has emerged in the context of climate change, can then be adopted as the umbrella concept, where resilience will be one factor influencing adaptive capacity. This improvement to conceptual clarity would foster much-needed communication between the natural hazards and the climate change communities and, more importantly, offers greater potential in application, especially when attempting to move away from disaster recovery to hazard prediction, disaster prevention, and preparedness.

Coastal cities: living on the edge.

Coastal cities: living on the edge.

Coastal mega-cities in Asia: transformation, sustainability and management

Coastal mega-cities in Asia have expanded rapidly and are heavily stressed from environmental perspectives. They have undergone momentous physical and socioeconomic transformations, posing severe problems in the utilization and misuse of resources in their immediate area and their hinterlands. Present patterns of coastal development and utilization are not sustainable. It calls for a comprehensive and informed framework to manage Asia's coastal regions, with education and a heightened awareness being the first steps to improvement.

Marine-related physical natural hazards affecting coastal megacities of the Asia–Pacific region – awareness and mitigation

The fast-growing, coastal megacities of the Asia–Pacific region are expanding into areas that are vulnerable to marine-related physical natural hazards, or, because of physical environmental changes, will become increasingly vulnerable within the timescale of city planning. The hazards comprise those that are due to extreme events such as storm surge and tsunami which may be catastrophic in their impacts; and those that relate to continuing changes over the long-term, notably global sea-level rise, sedimentary consolidation and coastal erosion. The latter may be exacerbated by human activities such as the increasing production of ‘greenhouse’ gases and over-abstraction of groundwater, and, while not threatening catastrophic loss of life or destruction of property, do have important economic and social implications for the future. There are two complementary approaches to hazard mitigation – constraining the hazard, and reducing vulnerability to the hazard. The contributions that science can make in the planning and implementation of sustainable adaptive measures are to improve the quantification of the incidence and severity of the various hazards, establishing realistic timescales of incidence, estimating return periods; and to establish the geographical limits of vulnerability to the hazards in a range of likely scenarios over timescales appropriate to the planning cycle. Contemporary, high risk, hazard scenarios for existing city developments demand an approach which focuses on effective warning networks and emergency planning; long-term, incremental hazards that are forecast to affect both developed and periurban areas can be addressed with a strategic planning approach, involving relocation and capital protective works. The selection of strategic measures demands the best possible predictive information on hazards and on vulnerability, including its full socio-economic evaluation so that the costs and benefits of the possible mitigation options can be realistically assessed. A predictive capacity, developed through modelling, requires the collection of reliable baseline and monitoring data relating to the hazards over a range of timescales in local, regional and global perspectives.

Coastal megacities and climate change

Rapid urbanization is projected to produce 20 coastal megacities (population exceeding 8 million) by 2010. This is mainly a developing world phenomenon: in 1990, there were seven coastal megacities in Asia (excluding those in Japan) and two in South America, rising by 2010 to 12 in Asia (including Istanbul), three in South America and one in Africa. All coastal locations, including megacities, are at risk to the impacts of accelerated global sea-level rise and other coastal implications of climate change, such as changing storm frequency. Further, many of the coastal megacities are built on geologically young sedimentary strata that are prone to subsidence given excessive groundwater withdrawal. At least eight of the projected 20 coastal megacities have experienced a local orrelative rise in sea level which often greatly exceeds any likely global sea-level rise scenario for the next century. The implications of climate change for each coastal megacity vary significantly, so each city requires independent assessment. In contrast to historical precedent, a proactive perspective towards coastal hazards and changing levels of risk with time is recommended. Low-cost measures to maintain or increase future flexibility of response to climate change need to be identified and implemented as part of an integrated approach to coastal management.