Adaptation in an Uncertain World—Detection and Attribution of Climate Change Trends and Extreme Possibilities
Xiyue Li and Gary Yohe
This chapter offers results from an artificial simulation exercise that was designed to answer three fundamental questions that lie at the heart of anticipatory adaptation. First, how can confidence in projected vulnerabilities and impacts be greater than the confidence in attributing what has heretofore been observed? Second, are there characteristics of recent historical data series that do or do not portend our achieving high confidence in attribution to climate change in support of framing adaptation decisions in an uncertain future? And finally, what can analysis of confidence in attribution tell us about ranges of “not-implausible” extreme futures vis-à-vis projections based at least implicitly on an assumption that the climate system is static? An extension of the IPCC method of assessing our confidence in attribution to anthropogenic sources of detected warming presents an answer to the first question. It is also possible to identify characteristics that support an affirmative answer to the second. Finally, this chapter offer some insight into the significance of our attribution methodology in informing attempts to frame considerations of potential extremes and how to respond.
Jubayer Chowdhury and Teng Wu
In this chapter, an effort has been made to give an overview of the aerodynamic loading on structures due to non-synoptic wind events, mainly tornadoes and downbursts. A brief description of the provisions in the building codes and standards for non-synoptic wind loads is presented. Current state of the art in simulating non-synoptic wind systems to obtain wind loads on structures is also discussed. The primary focus is buildings, bridges, and transmission lines in the discussion of the aerodynamic loading on structures. Finally, some insights are given on how future research in evaluating non-synoptic wind loads on structures might unfold.
Timothy P. Marshall and J. Arn Womble
Most building damage occurs at relatively low wind speeds, at or below 50 m s–1 (112 mph), as certain components fail, such as doors, windows, chimneys, and roof coverings. Rainwater then enters these openings, leading to interior damage. Structural failures usually begin with the removal of gable end walls, roof decking, and poorly attached roof structures as wind speeds increase; the greatest damage occurs at roof level as wind speeds increase with height above the ground. Internal wind pressure effects can lead to additional, more catastrophic damage, such as the removal of walls and ceilings. It is difficult to measure wind speeds directly on buildings as they would have to be instrumented well in advance of the storm, and there is no guarantee the storm would strike them. Furthermore, flying debris can damage pressure sensors on instrumented buildings. Thus, damage evaluators must infer failure wind speeds indirectly by studying damage left behind in the wake of windstorms. Therefore, it is important that damage evaluators know how buildings are constructed to better understand how they fail. This chapter identifies similar failure modes in residential structures regardless of wind type according to information from more than four decades of storm damage surveys. The information presented herein highlights some of the lessons learned in evaluating storm damage to wood-framed residential structures.
Cape Town’s Contested Hierarchy of Demand for Agricultural and Municipal Water in a Rainfed Economy 2017–2018
The article provides an analysis of the stakeholders involved in policy decision making on water utilization, especially during the Water Crisis of 2017–2018. It looks at this through the prism of the meetings and key informants of the South African Parliament Portfolio Committee on Water and Sanitation, the City of Cape Town Council and the farmers of the Western Cape. It also considers the effects of the prioritization of the use of water for drinking water and sanitation over agriculture. The South Africa water policy principles set by its Constitution and the Acts of 1996–1997 provide a comparator.
Hrvoje Kozmar and Branko Grisogono
There is a clear need to learn more about the exact characteristics of downslope wind storms in order to accurately address relevant topics in environmental aerodynamics and wind engineering. In particular, the characteristics of the atmospheric boundary layer are well known and provided in international standards and textbooks; however, further work is required to elucidate characteristics of downslope wind storms and make these characteristics available in a form suitable for engineering applications. While downslope wind storms have been successfully addressed in the meteorology, climatology, and geophysics communities, the focus of those groups is quite different from the focus in wind engineering; that is, the existing data on characteristics of downslope wind storms are of marginal relevance for engineering applications. It is therefore the scope of this chapter to provide a critical review of the state of the art on characteristics of those local and unique winds in comparison with the typical atmospheric boundary layer. It is expected that this work will encourage a more detailed codification of those winds. Another important goal is to enhance an interdisciplinary collaboration among the meteorology, geophysics, and engineering communities because it is shown in this chapter that the current wind engineering standards do not entirely keep up with the atmospheric physics of downslope wind storms.
Michael Gilmont, Lara Nassar, Erica Harper, Nadav Tal, and Steve Rayner
This chapter examines trends in water resources used in Jordan and Israel. Specifically it illustrates how these two economies have circumvented significant limits in their natural freshwater resource endowment to enable continued economic and population growth despite static or declining water availability. Using the concept of resource decoupling, it identifies four specific mechanisms by which economies can decouple their water needs from water availability, including economic diversification, food imports, agricultural water productivity, and nonconventional water resource development. Each of these mechanisms are illustrated for the two countries, including technical and political processes shaping their adoption. The chapter also critiques existing conceptualizations of decoupling relative to the water-specific model, highlighting the importance of understanding the unique characteristics of scarcity, flows, and substitutability of water at a global scale. Finally the chapter nests decoupling within the market modes framing this volume, before evaluating the risks and trade-offs inherent in decoupling strategies.
Kirsten D. Orwig
Convective storms affect countries worldwide, with billions in losses and dozens of fatalities every year. They are now the key insured loss driver in the United States, even after considering the losses sustained by tropical cyclones in 2017. Since 2008, total insured losses from convective storms have exceeded $10 billion per year. Additionally, these losses continue to increase year over year. Key loss drivers include increased population, buildings, vehicles, and property values. However, other loss drivers relate to construction materials and practices, as well as building code adoption and enforcement. The increasing loss trends pose a number of challenges for the insurance industry and broader society. These challenges are discussed, and some recommendations are presented.
Decision making under questions of deep uncertainty can be vague or specific, open-ended or fixed, easy or hard. This chapter very briefly addresses issues and approaches to decision making on adaptation to climate change. Depending on the research question, a complicated set of multiple approaches and tools may be needed. To highlight the types of approaches, this chapter discusses a variety of decision making tools and relates them to a particular problem: a homeowner choosing whether to do nothing, buy insurance, or elevate their home. The chapter culminates in a table summarizing the pros and cons of a variety of approaches.
Rob Wilby and Conor Murphy
Some of the most profound impacts of climate variability and change are expected in the water sector. These include more frequent, severe, and persistent droughts; more frequent, widespread, and extreme floods; more episodic and harmful water pollution episodes. Coping with more variable water supplies alongside rising demand will involve institutional reform, new infrastructure, adjustments to operations, and water demand management. A smarter, decision-led approach to deploying climate information in water management will also be required. This chapter begins with an overview of analytical frameworks for assessing and adapting water resource systems to uncertain climate threats and opportunities. It then gives examples of the diverse sources of information that are being accessed by some water managers to establish plausible ranges of climate change as a basis for decision-making. Examples from Denver, Colorado, and Dublin, Republic of Ireland show how narratives of future system changes and historical data can help test the efficacy of decisions under uncertainty. These two case studies demonstrate how early dialogue and information exchange among practitioners and scientists are fundamental to adaptation planning. In both places, unconventional sources of climate risk information were used to more rigorously stress test water management and planning assumptions. The preferred adaptation decision frameworks were dynamic, iterative, and open-ended. The chapter closes by acknowledging that further development of the decision-making approaches described herein may be needed to evaluate mixtures of adaptation options across multiple sectors.
Nourishing food and water are essential for human survival, as are the people who labour in the food system and the planetary ecosystems that underpin foraging, farming, and fishing. Our countries share one planet, woven together by inextricably linked natural and social systems. Global demand for food and water is increasing, while ecosystem decline, poverty, food insecurity, sociopolitical injustice, and racial inequities persist. Meeting food needs exerts tremendous pressure on planetary systems, yet fragmented social, political, economic, and environmental policies continue to threaten food system integrity and sustainability. Global food systems that reflect dietary patterns designed to promote food and water equity while respecting planetary limits, will require embracing values-informed, place-based policies and practices. Food system transformation represents an underutilized but very tangible avenue through which human and planetary well-being can be simultaneously reenvisioned and redirected toward a more health promoting, sustainable, equitable, and resilient future.
Alternative food movements have, from their origins, espoused values of social justice and environmental stewardship in an attempt to challenge existing economic and social norms related to food and farming. Three alternative food movements in North America exemplify the trade-offs between the three pillars of sustainable development: social equity, environment, and economy. Organic food has brought environmental benefits, but has struggled to challenge the status quo and promote the social benefits of the original movement when it goes to scale. Farmers’ markets have brought social and environmental benefits, but only in some cases reduced costs when compared to mainstream market levels. Consequently, good-quality food is often out of reach of low-income groups, as highlighted in a case study of access by underserved people in British Columbia, Canada. Regional food movements are a hybrid approach that balance some of the gains and some of the challenges of these systems. The extraordinary concentration of power in North American food systems stands in contrast to notions of social equity and undermines efforts to effect change in pursuit of sustainable alternative food systems.
Kevin M. Simmons
This chapter summarizes recent research first on the policy prescription of building codes designed with wind engineering principles, then on research concerning how markets for wind-enhanced construction offers other channels for increased resilience. Florida’s statewide building code was enacted after Hurricane Andrew; it was the first statewide building code designed for wind. But non-synoptic systems, such as tornadoes, also cause high levels of damage, so the city of Moore, Oklahoma, adopted a code to address that threat. The first purpose of this chapter is to conduct an analysis of the cost-effectiveness of these codes. An examination of other states that may also justify stronger codes follows. Finally, the chapter reviews research on how real estate markets value voluntary mitigation. Using markets for above-code construction provides opportunities to increase resilience in states where stronger building codes are not adopted.
Junji Maeda, Takashi Takeuchi, Eriko Tomokiyo, and Yukio Tamura
To quantitatively investigate a gusty wind from the viewpoint of aerodynamic forces, a wind tunnel that can control the rise time of a step-function-like gust was devised and utilized. When the non-dimensional rise time, which is calculated using the rise time of the gusty wind, the wind speed, and the size of an object, is less than a certain value, the wind force is greater than under the corresponding steady wind. Therefore, this wind force is called the “overshoot wind force” for objects the size of orbital vehicles in an actual wind observation. The finding of the overshoot wind force requires a condition of the wind speed recording specification and depends on the object size and the gusty wind speed.
Anthony J. Reynolds
Conservation agricultural practices have been widely adopted across the world in the past 30 years. Farmers recognized that their soils had been degraded by deep ploughing and by dependence on chemical fertilizers, pesticides, and herbicides. Conservation agriculture, involving the agronomic and technological practices of no-till, cover cropping, and rotation, can be a sustainable alternative to conventional farming both economically and environmentally. While improving soil and crop health, it also has a dramatic and beneficial impact on the soil structure and on organic matter content that in turn can improve drainage and the availability of water. Costs are greatly reduced and crop yields—after an initial decline—return to former levels. Increasing interest and uptake by the global farming community shows that the system can be adapted in a variety of farming situations and significantly aid both the environment and sustainable food production.
Rami Zurayk and Azza Dirar
Since agriculture consumes the largest share of the world’s water, farmers undoubtedly play an instrumental role in the management of this precious resource. As such, various policy approaches have sought to engage farmers in the management of water for irrigation. There is much literature on policy approaches that devolve irrigation management to farmers through organizing them into ‘water user associations’ and mobilizing them into cooperative water resource management. When the implementation experience and success of these approaches are assessed, the results show a great variation in experience with overall limited success. The key challenges stem from various assumptions underlying the policy approaches, namely the way in which farmers are conceptualized as a homogenous group of ‘water users’. Cooperative and participatory approaches to natural resource management cannot be institutionally manufactured without addressing key political ecological realities and the wider contexts in which ‘resource users’ operate.
Vanya Slavchevska, Susan Kaaria, and Sanna Liisa Taivalmaa
Male outmigration from rural, primary agricultural areas and the globalization of agri-food systems have both been linked to a significant increase in women’s work and responsibilities in agriculture, a phenomenon referred to as the ‘feminization of agriculture’. While the term has been broadly used to bring attention to the increasing number of women, relative to men, in agricultural employment, little attention has been paid to what the ‘feminization of agriculture’ means for women’s empowerment and their roles in agriculture more generally. Similarly, there is no clear understanding of how this will impact the agricultural sector and what the consequences for food and water security are. This chapter reviews the global evidence surrounding the “feminization of agriculture” and provides a critical discussion of the implications for women’s empowerment and for food and water security.
Mustapha Besbes, Jamel Chahed, and Abdelkader Hamdane
Northwest African countries (NA) consume 70 percent of their renewable water resources, and groundwater overdraft has become a major problem. Blue water irrigation represents 17 percent of overall water resources and is economically significant. Green water represents 83 percent, but is not yet well evaluated, and is not considered in national water strategies, along with virtual water embedded in international food trade. Irrigation enhances local agrifood production but it has not changed the proportion of staple foods. The region remains a major net food importer and, largely due to population increase, water dependency increased from 30 percent to 50 percent between 1970 and 2010. Population forecasts predict that water demand will continue to grow, and could reach more than three times the present level. Given the blue water status, NA must develop approaches to cope with water–food challenges, based on international virtual water flow optimization and better green water valorization.
Peter Johnston and Arthur Chapman
Irrigation is a critical input for raising food production in southern Africa, parts of which are food-insecure, especially as a result of low levels of technology employed, low investments into the sector, small farm sizes, and high levels of exposure to the hazards of climate variability. Most food production (including exports) and irrigation in the region occurs in the arid south—in South Africa by a large margin. Further north, in Angola, Zambia, and the northern parts of Mozambique, water resources are abundant yet irrigation farming is far less developed and inefficient, resulting in water resources being less intensely managed. The region needs to become more tightly integrated economically, with a greater flow of technology, investment, and management capability to the north, allowing the north to produce more food (and other agricultural products) which would flow to the more industrialized south—essentially virtual water flows to that region.
Michel Petit and Phillipe Le Grusse
The food and water challenges to be faced in the Mediterranean Basin, particularly those on the southern and eastern shores, are daunting. They form a complex nexus of problems and require policies pursuing several important potentially conflicting goals at the same time: reducing or limiting food import dependency through increased agricultural production in environmentally sustainable ways while protecting the natural resource base and keeping food affordable for poorer populations. The worrisome trends affecting countries on the southern and eastern shores of the common sea can also have seriously negative consequences in the North which explains why the North-South collaboration has a long tradition in the region. But, as the case of water management institutions shows, ineffective advocacy for trade liberalization has led to conflicts and tensions on various issues and has distracted attention from potentially much more fruitful areas of collaboration.
America Lutz Ley, Ryan Lee, Yulia Peralta, and Christopher Scott
The United-States-Mexico food system, and in particular the section located in the Sonoran Desert, is an example of the detrimental effects that result from instensified food production to supply increased demand from regional, transboundary, and global areas. Impacts to freshwater and terrestrial ecosystems in addition to human livelihoods and institutions create serious management and policy challenges. Understanding the region as an integrated water-food system with institutional imbalances reveals the following consequences: (a) an increasing reliance on groundwater resources for the majority of agriculture and livestock production; (b) a net export of nonrenewable water; and (c) a virtual water imbalance that further threatens the region’s water and food security.