81-100 of 274 Results

Article

Sharon E. Nicholson

This article provides an in-depth look at all aspects of the climate of the Sahel, including the pervasive dust in the Sahelian atmosphere. Emphasis is on two aspects: West African monsoon and the region’s rainfall regime. This includes an overview of the prevailing atmospheric circulation at the surface and aloft and the relationship between this and the rainfall regime. Aspects of the rainfall regime that are considered include its unique characteristics, its changes over time, the storm systems that produce rainfall, and factors governing its variability on interannual and decadal time scales. Variability is examined on three time scales: millennial (as seen is the paleo records of the last 20,000 years), multi-decadal (as seen over the last few centuries as seen from proxy data and, more recently, in observations), and interannual to decadal (quantified by observations from the late 19th century and onward). A unique feature of Sahel climate is that is rainfall regime is perhaps the most sensitive in the world and this sensitivity is apparent on all of these time scales.

Article

Western and Central Equatorial Africa (WCEA), home to the Congo rainforests, is the green heart of the otherwise dry continent of Africa. Despite its crucial role in the Earth system, WCEA’s climate variability has received little attention compared to the rest of Africa. Climate variability in the region is a result of complex interactions among various features acting on local and global scales. The mesoscale convective systems (MCSs) that have a preferentially westward propagation and present a distinct diurnal cycle are the main source of rainfall in the region. As a result of strong MCS activity, WCEA stands out as a convective anomaly within the tropics and experiences the world’s most intense thunderstorms as well as the highest lightning flash rates. The moisture of the region is supplied primarily from the Atlantic Ocean, with additional contributions from local recycling and East Africa. WCEA, in turn, serves as a moisture source for other parts of the continent. One striking characteristic of WCEA is its intrinsic heterogeneity with respect to interannual variability of rainfall, resulting in delineation of the region primarily in the zonal direction. This is in contrast to the meridionally oriented spatial variability of the annual cycle and underlines the fact that driving factors of the two can be quite different. The annual cycle is mainly determined by the seasonal excursion of the sun. However, the interannual and intraseasonal variability of the region are modulated by remote forcings from all three oceans, reflected via zonal atmospheric cells and equatorial wave dynamics. The local atmospheric jets and regional Walker-like circulations also contribute to WCEA’s climate variability by modulating the moisture transport and vertical motion. The region has experienced an increasing rate of deforestation in recent decades and has made a significant contribution to the global biomass burning emissions that can alter regional and global circulation, along with energy and water cycles. The mean annual temperature of the region has increased by about 1°C in the past 70 years. The annual rainfall over the same period presents a negative trend, though that is quite negligible in the eastern sector of the region.

Article

This is an advance summary of a forthcoming article in the Oxford Research Encyclopedia of Climate Science. Please check back later for the full article. Africa, a continent with the largest number of countries falling under the category of Least Developed Countries (LDCs), remains highly dependent on rain-fed agriculture that suffers from low intake of water, exacerbating the vulnerability to climate variability and anthropogenic climate change. The increasing frequency and severity of climate extremes impose major strains on the economies of these countries. The loss of livelihoods due to interaction of climate change with existing stressors is elevating internal and cross-border migration. The continent is experiencing rapid urbanization, and its cities represent the most vulnerable locations to climate change due in part to incapacitated local governance. Overall, the institutional capacity to coordinate, regulate, and facilitate development in Africa is weak. The general public is less empowered to hold government accountable. The rule of law, media, and other watchdog organizations, and systems of checks and balances are constrained in different ways, contributing to poor governance and resulting in low capacity to respond to climate risks. As a result, climate policy and governance are inseparable in Africa, and capacitating the government is as essential as establishing climate policy. With the highest level of vulnerability to climate change compared with the rest of the world, governance in Africa is pivotal in crafting and implementing viable climate policies. It is indisputable that African climate policy should focus first and foremost on adaptation to climate change. It is pertinent, therefore, to assess Africa’s governance ability to identify and address the continent’s needs for adaptation. One key aspect of effective climate policy is access to up-to-date and contextually relevant information that encompasses indigenous knowledge. African countries have endeavored to meet international requirements for reports such as the National Communications on Climate Change Impacts and Vulnerabilities and the National Adaptation Programmes of Action (NAPAs). However, the capacity to deliver on-time quality reports is lacking; also the implementation, in particular integration of adaptation plans into the overall development agenda, remains a challenge. There are a few successes, but overall adaptation operates mainly at project level. Furthermore, the capacity to access and effectively utilize availed international resources, such as extra funding or technology transfer, is limited in Africa. While the continent is an insignificant source of emissions on a global scale, a more forward looking climate policy would require integrating adaptation with mitigation to put in place a foundation for transformation of the development agenda, towards a low carbon driven economy. Such a futuristic approach calls for a comprehensive and robust climate policy governance that goes beyond climate to embrace the Sustainable Development Goals Agenda 2030. Both governance and climate policy in Africa will need to be viewed broadly, encompassing the process of globalization, which has paved the way to a new geological epoch, the Anthropocene. The question is, what should be the focus of climate policy and governance across Africa under the Anthropocene era?

Article

The expansion and intensification of summer monsoon precipitation in North and East Africa during the African Humid Period (AHP; c. 15,000–5,000 years before present) is recorded by a wide range of natural archives, including lake and marine sediments, animal and plant remains, and human archaeological remnants. Collectively this diverse proxy evidence provides a detailed portrait of environmental changes during the AHP, illuminating the mechanisms, temporal and spatial evolution, and cultural impacts of this remarkable period of monsoon expansion across the vast expanse of North and East Africa. The AHP corresponds to a period of high local summer insolation due to orbital precession that peaked at ~11–10 ka, and it is the most recent of many such precessionally paced pluvial periods over the last several million years. Low-latitude sites in the North African tropics and Sahel record an intensification of summer monsoon precipitation at ~15 ka, associated with both rising summer insolation and an abrupt warming of the high northern latitudes at this time. Following a weakening of monsoon strength during the Younger Dryas cold period (12.9–11.7 ka), proxy data point to peak intensification of the West African monsoon between 10–8 ka. These data document lake and wetland expansions throughout almost all of North Africa, expansion of grasslands, shrubs and even some tropical trees throughout much of the Sahara, increases in Nile and Niger River runoff, and proliferation of human settlements across the modern Sahara. The AHP was also marked by a pronounced reduction in windblown mineral dust emissions from the Sahara. Proxy data suggest a time-transgressive end of the AHP, as sites in the northern and eastern Sahara become arid after 8–7 ka, while sites closer to the equator became arid later, between 5–3 ka. Locally abrupt drops in precipitation or monsoon strength appear to have been superimposed on this gradual, insolation-paced decline, with several sites to the north and east of the modern arid/semi-arid boundary showing evidence of century-scale shifts to drier conditions around 5 ka. This abrupt drying appears synchronous with rapid depopulation of the North African interior and an increase in settlement along the Nile River, suggesting a relationship between the end of the AHP and the establishment of proto-pharaonic culture. Proxy data from the AHP provide an important testing ground for model simulations of mid-Holocene climate. Comparisons with proxy-based precipitation estimates have long indicated that mid-Holocene simulations by general circulation models substantially underestimate the documented expansion of the West African monsoon during the AHP. Proxy data point to potential feedbacks that may have played key roles in amplifying monsoon expansion during the AHP, including changes in vegetation cover, lake surface area, and mineral dust loading. This article also highlights key areas for future research. Among these are the role of land surface and mineral aerosol changes in amplifying West African monsoon variability; the nature and drivers of monsoon variability during the AHP; the response of human populations to the end of the AHP; and understanding locally abrupt drying at the end of the AHP.

Article

The geographic concept of tropicality emerged as an operative tool in the colonizing efforts of the European powers in the 18th and 19th centuries. Since the colonizing encounters proved fatal for many Europeans in South Asia, particularly during the initial phase of settlement when their mortality rate was far higher than that of the natives, attempts were made to understand the impact of the tropical climate upon the Western constitution. Based on the ancient Hippocratic doctrines of humoral pathology and the narrative of Enlightenment thinkers, colonial medical professionals endeavored to determine a correlation between health and environment. According to Western classical understanding, health was dependent upon various climatic and environmental factors. With the prevailing perception that the oppressive climatic conditions of India and its hazardous disease-infused environs were inimical to the survival of the Anglo-Indians in South Asia, the ancient concept of climatic determinism was revitalized during the colonial period. This theory, which argued that people tended to resemble the dominant characteristics of the climate in which they lived, proved convenient at a time of aggressive expansion, when moral grounds were required for justifying the Western designs of conquest and exploitation. Explanations like environmental determinism encouraged conjectures that the tropical climate of India bred only “lazy” and “degenerative” people, in contrast to the “manly” and “strong” individuals of the temperate zone. This notion, with its insidious veneer of rationality, facilitated a justification of the ideology of imperial colonization, while also discouraging permanent settlement of the European colonizers upon Indian soil.

Article

This is an advance summary of a forthcoming article in the Oxford Research Encyclopedia of Climate Science. Please check back later for the full article. Clustering techniques are used in the analysis of weather and climate to identify distinct, discrete groups of atmospheric and oceanic structures and evolutions from observations, reanalyses, and numerical model simulations and predictions. The goal of cluster analysis is to provide physical insight into states (and trajectories) that are preferred and also possibly unusually persistent, when such states can be identified and distinguished from the continuous background distribution of geophysical variables. “Preferred” states (or evolutions) are those that are significantly more likely to occur than would be predicted by a suitable background distribution (such as a multivariate Gaussian distribution), while “persistent” states are those with lifetimes distinctly longer than those of the background states. The choice of technique depends to a large extent on its application. For example, the identification of a small number of distinct patterns of the seasonal mean mid-latitude response to large seasonal mean shifts in tropical diabatic heating (perhaps due to the El Niño–Southern Oscillation) can be accomplished with the use of either a partitioning or hierarchical cluster analysis. The partitioning cluster method groups all states (maps of a given variable) into clusters so as to minimize the within-cluster variance, while the hierarchical analysis merges fields into groups based on their similarities. The identification of preferred patterns (whether or not they are tropically forced) on intra-seasonal time scales can also be accomplished in this way. The partitioning approach can easily be adapted to include multiple variables, and to describe tracks of localized features (such as cyclones). A variant of the partitioning cluster analysis, the “self -organizing map” approach, allows for a greater richness in cluster patterns and so can be useful on shorter, weather-related time scales. In either the partitioning or hierarchical analysis, each state (map) is identified uniquely with a given cluster. However, in certain applications it may be desirable to allow a given state to belong to multiple clusters with differing probabilities. In such cases one can estimate the underlying probability distribution function with a mixture model, which is a sum of a (usually small) number of component multivariate Gaussian distributions. The partitioning, hierarchical, and mixture model approaches, applied to a sequence of maps, all have one common feature: the sequencing (order in time) of the maps is not taken into account. This is not the case with the hidden Markov method, an approach that identifies not only preferred states but ones that are also unusually persistent. This approach, based on a simple neural network approach, makes use of an underlying “hidden variable” whose evolution is modeled by a Markov process. Each state is assigned to a number of clusters with a certain probability, but the most likely evolution of states from one cluster to another can be estimated. This approach can be generalized by letting the evolution of the hidden state be governed by a nonstationary multivariate autoregressive factor process. The resulting cluster analysis can then also detect long-term changes in the population of the clusters.

Article

In recent years, scientists have identified cognitive processes that short-circuit our deliberative faculties. In the domain of climate change in particular, a number of psychological barriers and biases may disrupt typical discourse and reflection and may even prevent those who are aware of climate change from taking action to mitigate or reduce its impact. These processes include the use of heuristic versions of calculation-based decisions to reduce processing load, which can make climate change judgments responsive to situational factors in the immediate decision context. Recent research in the decision sciences provides insight into how common biases in judgment inhibit rational deliberation about climate change, which may lead to the gap between society’s recognition of environmental problems and society’s frequent failure to address them appropriately. These insights involve the finite nature of human attention and cognitive resources, the complex interactions of personal experience and emotion, the challenges that uncertainty and risk place on behavior, and the profoundly social nature of human action. Understanding these barriers and systematic biases have led to a set of potential interventions, which demonstrate how practitioners can put research insights into practice in order to address a variety of sustainability challenges. One important direction for these interventions involves changing the decision context in ways that account for decision bias (e.g., using green defaults) and triggering more adaptive decisions as a result.

Article

The term public engagement (PE) refers to processes that provide a distinct role for citizens or stakeholder groups in policymaking. Such engagement is distinctive because it aims to create opportunities for mutual learning among policymakers, scientists, stakeholders, and members of the public. In so doing, PE involves a particular type of voice in public debate and policymaking that is different from more established discourses, such as those expressed through official policymaking channels, scientific institutions, civil society activists, or the public media. By the early 1970s, PE had emerged in the context of an overall democratization movement in Western societies through such innovations as the “citizen jury” in the United States and “planning cells” in Germany. Today, it is often more pragmatically motivated, such as in the European Commission, where PE is seen as a tool for responsible research and innovation that helps to anticipate and assess potential implications and societal expectations of research and innovation, as well as to design more inclusive and sustainable research policies. The first global PE processes in history were created to incorporate citizen voices into United Nations (UN) conventions on biodiversity and climate change. Building on theories of deliberative democracy and tested PE practices, a new World Wide Views process was developed to provide informed and considered input from ordinary citizens to the 2009 UN climate summit. This and subsequent World Wide Views (WWViews) deliberations have demonstrated that PE may potentially open up policy discourses that are constricted and obfuscated by organized interests. A telling example is provided by the World Wide Views on Climate and Energy deliberation held on June 5, 2015, where nearly 10,000 ordinary citizens gathered in 76 countries to consider and express their views on the issues to be addressed at the UN climate summit in Paris later that year. In a noteworthy departure from prevailing media and policy discourses, two-thirds of the participating citizens saw measures to fight climate change as “mostly an opportunity to improve our quality of life,” while only a quarter saw them as “mostly a threat to our quality of life,” a result that was consistent across high-, middle-, and low-income countries. Recent research on PE has indicated that when effectively implemented, such processes can increase the legitimacy, quality, and capacity of decision-making. Earlier aspirations for broader impacts, such as the democratization of policymaking at all levels, are now less prominent but arguably indispensable for achieving both immediate and longer-range goals. The relatively new concept of a deliberative system captures this complexity by moving beyond the narrow focus on single PE events encountered in much research to date, recognizing that single events rarely affect the course of policymaking. The evolving prospects for PE in biodiversity and climate change policy, therefore, can be seen as requiring ongoing improvements in the capacities of the deliberative system.

Article

Biofuels are produced from biomass, which is any organic matter that can be burned or otherwise used to produce heat or energy. While not a new technology—biofuels have been around for well over 100 years—they are experiencing something of a renaissance in the United States and other countries across the globe. Today, biofuels have become the single most common alternative energy source in the U.S. transportation sector with billions of gallons of the fuel produced annually. The expansion of the bio-based economy in recent years has been intertwined with mounting concerns about environmental pollution and the accumulation of carbon dioxide (CO2) in the earth’s atmosphere. In the United States, for example, biofuels mandates have been championed as key to solving not only the country’s increasing energy demand problems and reliance on foreign oil, but also growing fears about global climate change. Of course, the use of biomass and biofuels to combat global climate change has been highly controversial. While proponents argue that biofuels burn cleaner than gasoline, research has suggested that any reductions in CO2 emissions are offset by land use considerations and the energy required in the biofuels-production process. How publics perceive of climate change as a problem and the use of biomass and biofuels as potential solutions will go a long way toward determining the policies that government’s implement to address this issue.

Article

Carbon capture and storage (CCS) has emerged as a potential strategy for reducing greenhouse gas (GHG) emissions. It involves the capture of carbon dioxide (CO2) emissions from large point source emitters, such as coal-fired power plants. The CO2 is transported to a storage location, where it is isolated from the atmosphere in stable underground reservoirs. CCS technology has been particularly intriguing to countries that utilize fossil fuels for energy production and are seeking ways to reduce their GHG emissions. While there has been an increase in technological development and research in CCS, some members of the public, industry, and policymakers regard the technology as controversial. Some proponents see CCS as a climate change mitigation technology that will be essential to reducing CO2 emissions. Others view CCS as an environmentally risky, complex, and expensive technology that is resource-intensive, promotes the continued extraction of fossil fuels, and competes with renewable energy investments. Effective communication about CCS begins with understanding the perceptions of the general public and individuals living in the communities where CCS projects are sited or proposed. Most people may never live near a CCS site, but may be concerned about risks, such as the cost of development, environmental impacts, and competition with renewable energy sources. Those who live near proposed or operational projects are likely to have a strong impact on the development and deployment of CCS. Individuals in locally affected communities may be more concerned about disruptions to sense of place, impact on jobs or economy, or effect on local health and environment. Effective communication about the risks and benefits of CCS has been recognized as a critical factor in the deployment of this technology.

Article

In debates surrounding policy options for mitigating greenhouse gas (GHG) emissions, economists of various political stripes are near unanimous in their advocacy of putting a price on carbon, whether through a tax or emissions trading program. Due to the visible costs imposed on industry and consumers, however, these policies have been resisted by carbon-intensive industries and by an ideologically divided public, producing incentives for vote-seeking politicians to avoid implementing comprehensive and stringent carbon prices within their own borders. In this highly politicized environment, and considering the more recent diffusion of market-based instruments across political jurisdictions around the world, researchers have sought to identify the conditions most favorable to implementing carbon taxes and cap-and-trade programs, the correlates of public support for these policies, and the extent to which different communication strategies may help build public support. How do experts, political leaders, and members of the public understand these policy instruments, and what specific approaches have been most successful in persuading policy makers and the public to support a price on carbon? In places that have yet to implement a carbon price, what can communication strategists learn from existing research and the experience of other jurisdictions where such policies have been successfully implemented? In places where carbon taxes or carbon cap-and-trade programs exist, how are the benefits of these policies best communicated to ensure the durability of carbon pricing policies over time?

Article

Matthew A. Shapiro, Toby Bolsen, and Anna McCaghren Fleming

Public opinion plays a central role in determining the feasibility of efforts to transform energy systems in the coming years, yet scholarship on communication effects and public opinion about clean energy and energy efficiency seems to have expanded only relatively recently. There is a growing body of work that explores how targeted and strategically framed messages affect individuals’ beliefs and motivations to act on matters affecting household energy choices as well as energy policies. One must attend particularly to the principal communication-based factors that shape the public’s understanding of clean energy sources and promote efficiencies in energy use. To better understand the communication vehicles for improving both household energy efficiency and conservation, two research foci are most relevant: (1) field experiments that primarily assess how household energy consumption shifts after receiving energy consumption reports and (2) surveys/laboratory experiments that focus on the nuances of energy-related communications, paying particular attention to the role of politics and ideology. This bimodal classification of clean energy and efficiency communication research genres is not exhaustive but can be synthesized into two major contributions. First, providing households with information about specific benefits that would result from a greater reliance on clean energy may increase support for its development and move individuals toward energy efficiency outcomes; however, exposure to counter-messages that emphasize costs associated with clean energy and the associated policies can negate the effects of pro-clean energy messages. Second, there is still no reprieve from the politicization of energy, and thus the role of partisanship and motivated reasoning must be accounted for when assessing how individuals modify their decision-making processes regarding energy efficiency.

Article

Christopher E. Clarke, Dylan Budgen, Darrick T.N. Evensen, Richard C. Stedman, Hilary S. Boudet, and Jeffrey B. Jacquet

The impacts associated with unconventional natural gas development (UGD) via hydraulic fracturing have generated considerable controversy and introduced terms such as “fracking” into the public lexicon. From a climate change perspective, transitioning from fossil fuels to renewable sources in order to potentially avoid the worst consequences of a warming planet will need to also consider the climate implications of increased UGD and natural gas use that follows. Specifically, how much greenhouse gas is emitted as natural gas is extracted, transported, and consumed relative to other energy sources? Is UGD a “cleaner” energy source? Compared to what? Does it postpone or “bridge” the transition from fossil fuels to renewable energy? Public perception of UGD’s climate impacts not only reflect individual attitudes but broader social discourse among stakeholder groups. Understanding these perceptions, their psychological and social factors antecedents, and how to engage audiences on this topic will play a key role in UGD’s long-term trajectory, especially as it relates to climate change. An added challenge is that most public opinion studies specific to UGD’s climate impacts (and indeed UGD in general) are limited to the United States, Canada, and a few countries in Europe and Africa, with other parts of the world entirely absent. Nonetheless, the studies that do exist highlight several common themes. In particular, UGD tends to be viewed as cleaner relative to fossil fuels because of the belief it produces less carbon emissions as a result of natural gas extraction and consumption. However, it tends to be viewed as dirtier relative to renewables amid the belief that it increases carbon emissions. This finding complements research showing that natural gas occupies a middle ground between renewables and other fossil fuels in terms of acceptance. Moreover, the extent UGD serves as a bridge energy source remains contentious, with some arguing that it and the natural gas it produces complement fossil fuels and facilitates a transition to renewables, while others claim that UGD entrenches society’s continued reliance on the former. Overall, despite the contentious nature of these issues, UGD’s climate impacts appear less salient across countries than other health, environmental, and economic impacts, perhaps because they are psychologically distant and difficult to experience directly. Amid efforts to convey the public health risks associated with a changing climate, we believe that emphasizing the public health dimensions of UGD’s climate impacts can potentially make them more psychologically tangible. Positively framed messages emphasize that reducing carbon emissions tied to both unconventional natural gas extraction and natural gas consumption (relative to other fossil fuels) and thus mitigating the resultant climate change that follows benefits public health. Conversely, negatively framed messages emphasize that increasing carbon emissions (relative to renewables) and thus amplifying the resultant climate change adversely affects public health. At present, though, there is little evidence as to how these messages affect the perceived connection between UGD’s climate impacts and public health and, in turn, support for UGD versus other energy types. Nor is it clear how these outcomes may vary across countries based on public sentiment toward UGD and climate change along with a variety of psychological and social factors that influence such sentiment. Data available for some countries offers tantalizing scenarios, but we remain limited due to the lack of social science research in countries outside the United States and a handful of others. We call for cross-national comparative studies that include places where UGD—and social science research on it—is still maturing.

Article

Within the corporate sector, climate change represents an unfolding market shift, one that is driven by policy but also by pressures from a variety of market constituents such as consumers, suppliers, buyers, insurance companies, banks, and others. The shift takes place in both mitigation of greenhouse gas emissions and adaptation to the physical effects of a changing climate. It is manifest in shifts in market demand, cost of capital, operational efficiency, energy efficiency, access to raw materials within supply chains, and other issues of business concern. In fact, when viewed in this way, business leaders and stakeholders can be agnostic about the science of climate change and still see it as a business issue. In the face of a market shift, successful companies must innovate. And as in any market shift, the implications of addressing climate change are not uniform; the burden will not fall evenly. There are both risks and opportunities; there will be both winners and losers. Certain companies, industries, and sectors will be impacted more than others. This article will discuss the ways in which climate change poses market risk and the strategic responses that companies might adopt to respond to and mitigate that risk. This focus is critically important as the solutions to climate change must come from the market. The market is the most powerful institution on earth, and business is the most powerful entity within it. The market compels business to make the goods and services we rely upon: the clothes we wear, the food we eat, the forms of mobility we use, and the buildings we live and work in. If the market does not lead the way toward solutions for a carbon-neutral world, there will be no solutions.

Article

Mark Morrison, Donald W. Hine, and Steven D'Alessandro

Communication with farmers about climate change has proven to be difficult, with relatively low acceptance of anthropogenic climate change or the idea that climate change will negatively affect agriculture. Many farmers have been impervious to climate change communications because of the nature of farming, their worldviews, and the controversies about climate change in the media. Segmentation studies from the agriculture and natural resource management literatures provide evidence of homogeneous farmer groups internationally with respect to climate change attitudes and behaviors in a farming context. Understanding these segments—including their values, beliefs, and behaviors—is important for developing tailored and targeted communications approaches. Based on understanding of commonly observed farmer segments, it is possible to tailor communication strategies to better engage with segments of concern, including which message to use, appropriate sources, as well as alternative communication techniques based on participatory approaches and use of the arts. For certain segments, discussion about human-induced climate change should be avoided given that it is contentious and not critical for how farmers should respond to climate change. Theoretical frameworks from psychology and marketing—such as the theory of planned behavior, the attitude-to-behavior process model, the motivation and opportunity and determinants (MODE) model, motivation to avoid harm, and the elaboration likelihood model—can also be used to inform the design of communication strategies for engaging with farmers. However, a careful analysis of farmer segments, their worldviews, their beliefs, and their position in the consumer decision-making process suggests that the recommendations from these theoretical models should not be implemented uniformly across farmer segments. Rather, the various theoretical models provide a number of strategies that need to be selectively applied based on knowledge of the target segment. While use of theory and understanding of segments will help to improve communications with farmers, it is apparent that changing the beliefs of farmers in some segments about the need to respond to climate change will require more than simply increasing the quantity or quality of communications. Engaging farmers in these segments requires a much richer information set and a much greater effort to show farmers how they should be responding to climate variability and change using practical demonstrations and participatory approaches.

Article

The relationship between scientific experts and news media producers around issues of climate change has been a complicated and often contentious one, as the slow-moving and complex story has frequently challenged, and clashed with, journalistic norms of newsworthiness, speed, and narrative compression. Even as climate scientists have become more concerned by their evidence-based findings involving projected risks, doubts and confusion over communications addressing those risks have increased. Scientists increasingly have been called upon to speak more clearly and forcefully to the public through news media about evidence and risks—and to do so in the face of rapidly changing news media norms that only complicate those communications. Professional science and environment journalists—whose ranks have been thinned steadily by media industry financial pressures—have meanwhile come under more scrutiny in terms of their understanding; accuracy; and, at times, perceived bias. A number of important organizations have recognized the need to educate and empower a broad range of scientists and journalists to be more effective at communicating about the complexities of climate science and about the societal and economic impacts of a warming climate. For example, organizations such as Climate Communication have been launched to support scientists in their dealings with media, while the United Nations Intergovernmental Panel on Climate Change itself has continued to focus on the communication of climate science. The Earth Journalism Network, Society of Environmental Journalists, Poynter Institute, and the International Center for Journalists have worked to build media capacity globally to cover climate change stories. Efforts at Stanford University, the University of Oxford, Massachusetts Institute of Technology, Harvard University, and the University of Rhode Island sponsor programming and fellowships that in part help bolster journalism in this area. Through face-to-face workshops and online efforts, The Yale Project on Climate Change Communication has sought to link the media and science communities. Meanwhile, powerful, widely read sites and blogs such as “Dot Earth,” hosted by the New York Times, Climate Central, Real Climate, The Conversation, and Climate Progress have fostered professional dialogue, greater awareness of science, and called attention to reporting and communications issues. Journalists and scientists have had ongoing conversations as part of the regular publication and reporting processes, and professional conferences and events bring the two communities together. Issues that continue to animate these discussions include conveying the degree to which climate science can be said to be “settled” and how to address uncertainty. Through some of these capacity-building efforts, news media have become increasingly aware of audience dynamics including how citizens respond to pessimistic reports, or “doom and gloom,” versus solutions-oriented reports. Professional dialogue has also revolved around the ethical dimensions of conveying a story at the level of global importance. Still, with issues of climate change communication on display for more than two decades now, certain tensions and dynamics persist. Notably, journalists seek clarity from scientists, while climate change experts and advocates for and against taking climate action often continue to demand that journalists resist the temptation to oversimplify or hype the latest empirical findings, while at the same time urging that journalists do not underestimate potential climate risks.

Article

Ishani Mukherjee and Michael Howlett

Policy communication and the resulting influence that information has on policy decision-makers is an especially pertinent topic when it comes to problems of climate change. Notorious for its complexity, uncertainty, and divergence of viewpoints, climate change has earned the title of being the major “wicked” or “super-wicked” problem of our times. A proliferation of expertise, interests, and capacities mark the climate change policymaking landscape and this density of players warrants an advanced framework to understand the ways in which the variety of climate-pertinent knowledge is communicated to policymakers. Moving beyond undifferentiated “two-communities” models of knowledge utilization in policymaking which limit the discussion to the bilateral interactions between knowledge experts or “producers” and information “consumers” of the public sector, this article explores the concept of a policy advisory system, which embodies the different sets of influence that various policy actors can have during policy decision-making and how communication between and among actors is a significant aspect of climate change policymaking. The concept of policy advisory systems is an important new development in the policy studies literature and one that is analytically very applicable to climate policy contexts. Suitably generalizable across representative policy settings, policy advisory systems are comprised of distinct groups of actors who are engaged in the definition of policy problems, the articulation of policy solutions, or the matching of policy problems to solutions. We explore how individual members of these separate sets of actors—namely the epistemic community, which is occupied in discourses about policy problems; the instrument constituencies which define policy instruments; and the advocacy coalitions which compete to have their choice of policy alternatives adopted—interact and communicate with policymakers across climate change policy activities.

Article

Communicating about climate change with religious groups should recognize the diversity incorporated in the term “religion.” Diversity in practice, institutional forms, belief systems, values, and core narratives mean that climate communication cannot be formulaic application of communication techniques and social psychology tweaked for spirituality. Because all people see phenomena like climate change through the prisms of their existing ideas, values, influence of significant others, sociostructural position, and personal experience, and expect these to be respected, communication with religious groups should respect the particular religious tradition and draw on narratives and language that are meaningful to the particular faith. Emphasis is placed on the role of religion as a social space wherein people come together, form ideas, and act collectively. Social networks and established practice are likely to be as significant as the influence of a religious leader although such elite influence can also be important. Roman Catholic Pope Francis’ recent teaching document on the environment, Laudato Si’: On Care for Our Common Home, serves as one example of communication about climate change. An understanding of the cultural assumptions, narratives, and framings relevant to a particular group is essential regardless of whether the people are secular or religious.

Article

Cities are important venues for climate change communication, where global rhetoric, national directives, local priorities, and media discourses interact to advance mitigation, adaptation, and resilience outcomes on the ground. Urban decision makers are often directly accountable to their electorates, responsible for the tasks most relevant to advancing concrete action on climate change, and flexible in pursuing various public engagement programs. However, many cities are designing climate policies without robust downscaled climate projections or clear capacity and support mechanisms. They are often constrained by fragmented governance arrangements, limited resources, and jurisdictional boundaries. Furthermore, policies often fall short in responding to the disparate needs of heterogeneous urban populations. Despite these constraints, cities across the global North and South are innovating with various communication tools to facilitate public awareness, political engagement, context-specific understanding, and action around climate change. These tools range from traditional popular media to innovative participatory processes that acknowledge the interests of different stakeholders, facilitate engagement across institutional boundaries, and address persistent scientific uncertainty through information coproduction and knowledge reflexivity. By selectively employing these tools, local governments and their partners are able to translate climate science into actionable mitigation, adaptation, and resilience plans; prioritize decision making while taking into account the multiscaled nature of urban infrastructures and service provisions; and design adaptable and flexible communication processes that are socially equitable and inclusive over the long term.

Article

Jill E. Hopke and Luis E. Hestres

Divestment is a socially responsible investing tactic to remove assets from a sector or industry based on moral objections to its business practices. It has historical roots in the anti-apartheid movement in South Africa. The early-21st-century fossil fuel divestment movement began with climate activist and 350.org co-founder Bill McKibben’s Rolling Stone article, “Global Warming’s Terrifying New Math.” McKibben’s argument centers on three numbers. The first is 2°C, the international target for limiting global warming that was agreed upon at the United Nations Framework Convention on Climate Change 2009 Copenhagen conference of parties (COP). The second is 565 Gigatons, the estimated upper limit of carbon dioxide that the world population can put into the atmosphere and reasonably expect to stay below 2°C. The third number is 2,795 Gigatons, which is the amount of proven fossil fuel reserves. That the amount of proven reserves is five times that which is allowable within the 2°C limit forms the basis for calls to divest. The aggregation of individual divestment campaigns constitutes a movement with shared goals. Divestment can also function as “tactic” to indirectly apply pressure to targets of a movement, such as in the case of the movement to stop the Dakota Access Pipeline in the United States. Since 2012, the fossil fuel divestment movement has been gaining traction, first in the United States and United Kingdom, with student-led organizing focused on pressuring universities to divest endowment assets on moral grounds. In partnership with 350.org, The Guardian launched its Keep it in the Ground campaign in March 2015 at the behest of outgoing editor-in-chief Alan Rusbridger. Within its first year, the digital campaign garnered support from more than a quarter-million online petitioners and won a “campaign of the year” award in the Press Gazette’s British Journalism Awards. Since the launch of The Guardian’s campaign, “keep it in the ground” has become a dominant frame used by fossil fuel divestment activists. Divestment campaigns seek to stigmatize the fossil fuel industry. The rationale for divestment rests on the idea that fossil fuel companies are financially valued based on their resource reserves and will not be able to extract these reserves with a 2°C or lower climate target. Thus, their valuation will be reduced and the financial holdings become “stranded assets.” Critics of divestment have cited the costs and risks to institutional endowments that divestment would entail, arguing that to divest would go against their fiduciary responsibility. Critics have also argued that divesting from fossil fuel assets would have little or no impact on the industry. Some higher education institutions, including Princeton and Harvard, have objected to divestment as a politicization of their endowments. Divestment advocates have responded to this concern by pointing out that not divesting is not a politically neutral act—it is, in fact, choosing the side of fossil fuel corporations.