Water management in the Washington Metropolitan Area (WMA) is challenging because the system relies on flow in the Potomac river, which is largely uncontrolled and augmented by the Jennings-Randolph reservoir, located 9-10 days travel time upstream. Given this lag, release decisions must be made collectively by federal, state and local stakeholders amid significant uncertainty, well in advance of accurate weather forecasts with no ability to recapture excess releases. Adding to this uncertainty are predictions of more severe and sporadic rainfall over the next century, caused by anthropogenic climate change. This study aims to evaluate the potential impacts of demand and climate change on the WMA water supply system, identifying changes in system vulnerability over the next century and developing adaptation strategies designed to maximize efficiency in a nonstationary system. A daily stochastic streamflow generation model is presented, which succesfully replicates statistics of the historical streamflow record and can produce climate-adjusted daily time-series. Using these time series, a multi-objective evolutionary algorithm is used to optimize the system's operating rules given current and future conditions, considering several competing objectives. / Ph. D.

The advent of climate change promises extreme disruptions to existing concepts of political time, namely the distinction between the modes of time adopted by modern nation-states, natural time, and the everyday life of human beings. Yet the nation-state remains the primary actor through which climate politics is shaped. India is one the most prominent actors in the UN Framework Convention on Climate Change (UNFCCC) and also likely to be one of the most climate-affected societies moving forward. Over the 30-year history of India's engagement at the UNFCCC, there has been a shift from constructing a secular, past-oriented imaginary to a sacred, future-oriented one. The state has fostered these temporal imaginaries through three discursive registers: international politics, climate science, and conservative Hindu ideology. These imaginaries act as a heuristic tool with which to analyze the changing dynamics of political temporality in an era of rapid and extreme climate change. / Doctor of Philosophy / Climate change challenges fundamental notion of political time, the temporal relationship that embeds actors and processes. Yet this topic is underanalyzed in academic literature, especially when it comes to non-Western states. India has been one of the most prominent actors at the United Nations climate negotiations and also likely to be heavily affected by extreme climate shifts. Over the 30-year history of the UN Framework Convention on Climate Change (UNFCCC), the Indian government has framed the temporality of climate change in two ways. First, from 1988-2004, it constructed and followed a secular, past-oriented imaginary of climate change. Beginning in 2005, and accelerating with the election of Prime Minister Modi in 2014, the government has begun to construct and follow a sacred, future-oriented imaginary. In this way, the State has moved from rhetorically framing climate change as a significant problem to an opportunity that can be met if India and other societies follow conservative Hindu precepts.

This research uses a mixed methods approach to analyze recent climate and land use changes, and farmers\' perceptions of climate change and its impacts on traditional agriculture in the village of Keur Samba Guéye (KSG). This work looks at the influence of social beliefs in adoption of new strategies by small farmers in this region, a topic that has received little or no study to date. Traditional agriculture in KSG is not very productive at present because of the impoverishment of the area and traditional agricultures strong dependency on natural climatic conditions. In this research, I identified recent climatic trends, documented changes in land use/land cover (LULC) from 1989 to 2011, and assessed farmers\' perceptions of climate change and their responses to such changes. To document climate trends and LULC, I analyzed climate data of twelve meteorological stations located across the country and created a classification of satellite images of KSG for two time periods. To examine farmers\' perceptions and agricultural practices, I conducted surveys of the farmers of KSG and in surrounding villages. Most farmers reported negative impacts of climate change on their agriculture activities, and interest in adopting new agricultural strategies despite long-standing tradition. Increasing temperatures and irregularity of rainfall may have negatively impacted crop yields, but more climate data are needed to clarify this phenomenon. LULC has been influenced by both climate change and human pressure; agricultural land has declined, while bare soils have increased. Several recommendations are provided that may help farmers to cope with changing climate. / Master of Science

Climate change is a natural cyclical phenomenon and throughout our planet's existence there have been sustained periods of heating and cooling. These periods are often referred to as "ice ages" and "interglacials" respectively. Scientists attributed warms oceans and carbon dioxide released from the oceans as the reason for global warming in the past. However, human activities of the recent past, mainly the burning of fossil fuel has seen an amplification of global temperature at a scale never seen before. This unprecedented change in our environment, as per scientists will have adverse side effects and have a long-term impact in our world. The most likely effects of climate change will be; heatwave, drought, glacier melts, sea level rise, erratic precipitation and erosions depending on a particular geographical location. The socio-economic impact of climate change could be a severe one too. Heat and drought could have major impact on agriculture, food and forests. United Nations data released in 2016 suggests that by the year 2050, more than 50 percent of the world's population will face a dearth of fresh water sources. It is also predicted that water scarcity will most likely result in diseases, unemployment and poverty. Energy use is also likely to increase with the greater need for air conditioning in the summer and heating in the winters. In cases where a region can't cope with these consequences, mass migration in search of better conditions is also likely. Physical and economic infrastructure will be tested by severe weather, flooding, wildfires and other phenomena. Data published by the United Nations in 2014 estimated that more than 50% of the world's total population lives in the urban areas and soon that number is likely to increase to 60%. In conjunction with climate change, this will mean more strain on already stretched resources in urban ecosystems. Also, with data suggesting that many people will migrate due to unemployment and poverty because of climate change, it is highly likely urban regions will have to accommodate that population too. The intertwined nexus of freshwater shortage, food, water and energy security is an issue we are already grappling with today, which is likely to be exacerbated in the future. These issues cannot be reviewed and analyzed as separate phenomena, but rather as a single intertwined phenomenon. The solution of the problem, hence, should be treated as the same. / Master of Architecture / This thesis, initially, investigates the phenomenon of climate change, and the likely challenges that it might pose in the future. Sustained periods of heating and cooling is a natural cyclical process, but human activities of the recent past has amplified global warning. This, according to scientists, will impact earth in the long run, and will have climatological and socio economic consequences. Water scarcity, droughts, sea level rise, mass migration are identified as problems that could intensify in the future. At various regions across the world, we are already facing these issues at different scales. This thesis, hence identifies the most pertinent future challenges and simulates those with existing societal challenges. The aim of the thesis is to provide an integrated and holistic plan to address the issues at hand with a view that the approach would also adapt to and mitigate issues in the future. Natural cycles and resources are used as a model to develop a mechanism to create a built environment for a small, self sustaining community. The proposed design is a prototype for a particular climatic scheme, but could be altered to fit other climatic criteria. The scheme through, research, addresses contemporary societal needs and tries to provide a solution contingencies of climate change.

Amphibians are influenced by climate change, but we do not have a clear understanding of how changes in temperature, precipitation, or both, may influence amphibian larvae in temperate regions. Do amphibian larvae have similar developmental responses to increased temperature and increased drying rates of wetlands - both plausible effects of climate change? What influence do the interactive effects of temperature and drying have on the relationships between the larval responses themselves (e.g., survival, body size, and time to metamorphosis)? To address these questions, we studied larval responses of two amphibian species, wood frogs (<em>Lithobates sylvaticus</em>) and spring peepers (<em>Pseudacris crucifer</em>), to simulated warming and drying in experimental ponds. Over 13 weeks, we manipulated temperature and water levels in ponds to produce 4 treatments: control, drying, warming, and drying + warming. Our manipulations created warming treatments that were on average 2 ° C higher than controls, and our drying treatments decreased in water depth by 2.5 cm each week compared to warming and control treatments that held a consistent amount of water. In both species, warming treatments resulted in significantly earlier timing of metamorphosis, and drying treatments resulted in significantly reduced body size. We saw a negative relationship between body size and time to metamorphosis (i.e., individuals that metamorphosed faster generally had larger body sizes), indicating an unexpected decoupling of the typical positive relationship between time to- and size at metamorphosis. The strength of the relationship between responses also varied by treatment for wood frogs but not spring peepers, indicating that the responses of larval amphibians to climate change may vary among species. Our study reveals complex relationships among larval survival, body size, and time to metamorphosis and highlights the need for considering not only the role of interacting climate-related pressures on amphibians but also the mechanisms underlying coupling of larval responses to these pressures. We encourage future research and discussion on a better understanding of why different climate pressures caused different responses, and if these patterns may be consistent in other aquatic species. / Master of Science / Across the globe, shifts in temperatures and the availability of freshwater habitats due to climate change are presenting challenges as well as opportunities for many species, particularly those that rely on freshwater habitats to complete their life cycle. Climate change is leading to warmer water temperature and accelerated drying of wetlands and ponds. Warming and drying often occur simultaneously, yet our understanding of how warming and drying may interact and affect sensitive aquatic species is limited. Amphibians with an aquatic life stage (for example, frog tadpoles) are particularly vulnerable to the effects of climate change on wetlands and ponds because they must transform from swimming larvae to land-dwelling adults before aquatic habitats dry out. Warming and drying help amphibian larvae determine when to start that process, called metamorphosis. For this reason, amphibian larvae in aquatic habitats are especially vulnerable to shifts in water temperature and the timing of drying. In this thesis, I explore how warming and drying influence amphibian survival, body size, and time to metamorphosis. To better understand the responses of amphibian larvae to warming and drying, I tested the effects of warming and drying on three response variables: amphibian survival, body size, and time to metamorphosis. I used two different species, wood frogs and spring peepers, to determine whether frogs' responses vary among species. I created an artificial pond experiment where I filled large tanks to represent natural ponds in a controlled, outdoor setting. In these artificial ponds, I measured wood frog and spring peeper growth under experimentally increased water temperatures and accelerated drying levels over 13 weeks. I found a negative relationship between body size and time to metamorphosis, suggesting individuals who spent less time in the water as larvae were more likely to be larger than individuals who spent more time in the water as larvae. Additionally, ponds with higher larval survival were associated with larger body size and a shorter time to metamorphosis. Warmer water temperatures led to a shortened time to metamorphosis but did not always lead to higher body sizes. Accelerated drying did not lead to a shortened time to metamorphosis, but it did lead to smaller body sizes in both species compared to control and warming ponds. Overall, I found complex relationships among larval responses with the directions of responses varying between treatments and species. This highlights the need for considering the role of climate-related changes in the environment (warming and drying) as well as the interactions between specific larval responses to those environmental changes. By understanding how warming and drying influence amphibian larval success, we can make a more direct link between climate change and its effects on aquatic larvae. Incorporating the responses between survival, body size, and time to metamorphosis to gain a more complete understanding of amphibian larval responses to the changing climate is an important step toward conserving and protecting freshwater aquatic species.

The atmospheric effect of greenhouse gas emissions is posing an increasing threat to the stability of the global climate. Like many developing nations, the western Africa nation of Nigeria faces risks from climate change, with potential effects on the environment upon which Nigerians rely and on broader social constructs, including the national economy. Nigeria's diverse topography, which stretches from dry northern regions of the sub-Sahara to lush southern rainforests along the Gulf of Guinea, accentuates susceptibility to a variety of climate-related hazards, including warming, irregular rainfall patterns, and extreme weather occurrences. Driven by the influence of tropical climates on the global climate system and the importance of climate variability and change specifically within Nigeria, this study of the Nigerian hydroclimate explicitly characterizes historical variability and change through analysis of in-situ daily climate data. Daily maximum and minimum air temperature and total precipitation data from 1982 through 2011 were obtained from the Nigeria Meteorological Service for 20 locations across the country. Given the limited temporal extent of the data, two popular satellite-derived precipitation products were tested for usability as supplements to the in-situ data. Each of the satellite-derived products depicts rainfall with an unrealistically high frequency and with a temporal trend that is opposite reality. Only in-situ data were analyzed further, beginning with a methodology to define the climatological wet and dry seasons across the country. The critical wet season across Nigeria was found to last between 120 days (north) and 200 days (south), beginning April/May and ending September/October, with wetness migrating from nearer the southern coastline northward through the country during the Northern Hemisphere summer, before retreating south again. As with seasonality, the spatial distribution of precipitation amount and frequency relates to distance northward from the southern coast. Wet season precipitation approaches 2500 mm from an average of more than 115 wet days along the coast, to only about 350 mm and 35 days across far northern Nigeria. Conversely, the dry season produces 300 mm from 30 wet days across the south, and only 80 mm from less than 10 days across the north. The wet season in Nigeria accounts for greater than 90% of annual precipitation and number of wet days. Nigeria experienced a warming and wetting of the climate during the 30-year study period, during both the wet and dry seasons. However, a change in the equitable distribution of precipitation across wet days (i.e., daily intensity) is not greatly evident, as it is for many other regions of the world. Thus, the likely benefit of greater precipitation does not appear to be mitigated by the risks associated with an increase in the frequency of high-intensity rainfall events. But tempering the positive precipitation signal is the likely detrimental effect of warming. Inter-annual variability in the wetness of the critical wet season is evident in the synoptic atmospheric expression of the inter-tropical convergence zone/discontinuity, but also in sea surface temperatures within the Gulf of Guinea. Historically, sea surface temperatures are considerably higher during the wettest wet season years compared to the driest years, possibly indicating a short-distance teleconnection that may offer seasonal predictability. / Master of Science / Nigeria is experiencing the consequences of global climate change caused by gases that trap heat in the atmosphere. Nigeria is endowed with a diverse terrain, with green rainy parts in the south and arid regions in the north. In Nigeria, the economy and the environment are both being impacted by climate change. Decades of climatic data from various regions of the nation were examined in this research. We discovered that Nigeria is generally becoming wetter and warmer. Most of the yearly precipitation falls during the rainy season, which runs from April to October. There hasn't been much of an increase in extremely heavy rain, though, because the intensity of the rainfall hasn't increased significantly. However, higher temperatures can lead to issues. The amount of rain that falls in Nigeria is also influenced by sea surface temperature in the Gulf of Guinea. This study sheds light on how Nigeria's weather is changing due to climate change, which may have negative effects on both people and the environment.

No / The impact of rapid climate change on contemporary human populations is of global concern. To contextualize our understanding of human responses to rapid climate change it is necessary to examine the archeological record during past climate transitions. One episode of abrupt climate change has been correlated with societal collapse at the end of the northwestern European Bronze Age. We apply new methods to interrogate archeological and paleoclimate data for this transition in Ireland at a higher level of precision than has previously been possible. We analyze archeological 14C dates to demonstrate dramatic population collapse and present high-precision proxy climate data, analyzed through Bayesian methods, to provide evidence for a rapid climatic transition at ca. 750 calibrated years B.C. Our results demonstrate that this climatic downturn did not initiate population collapse and highlight the nondeterministic nature of human responses to past climate change.

Master of Science / Department of Communications and Agricultural Education / Lauri M. Baker / The purpose of this study was to explore the frames and messages, issue salience, and communication preferences agricultural producers in Kansas, Oklahoma, and Texas use and accept related to climate change and the impacts of a changing climate. It was of additional interest to explore the climate-change beliefs and preferred agricultural media sources for climate and climate change information. Specific research objectives to guide the study were RO1: describe the level of issue salience agricultural producers have related to climate change; RO2: investigate frames and messages agricultural producers prefer in reference to the scientifically designated phenomena of climate change and impacts; and RO3: identify the agricultural media and information channels agricultural producers use for climate change. Based on findings in previous research, one hypothesis was developed: H1: agricultural producers in the Southern Plains Regional Climate Hub area will be located within the audience segment groups of the concerned and the cautious as identified in the Six America’s (2012) study. An Internet survey was distributed to producers in Kansas, which was open from March 3 to March 14, 2016, with 158 responses to the survey. Agenda-Setting Theory served as the basis for the study including the tenants of issue salience and framing in relation to climate change. The study found that the majority (n = 158, 64.92%) of producers believed that climate change was occurring, however, the causes were still contested. The study identified that higher levels of risk perception and education level were linked to belief in anthropogenic climate change (ACC). Primarily, the study found that loss framing was most effective in communicating the impacts of climate change. Terminology and distance framing were less important in message framing. Regional and university publications were cited most frequently by producers as sources of climate and climate-change information and overall use of agricultural media publications was linked to higher levels of belief in ACC. Users of business reports and TV had the highest mean climate-change belief; non-users had the lowest. Audience segments aligned with cautious and concerned Six America’s (2013) audience segment group, which indicated a shift towards accepting climate change among agricultural producers.

<p>Climate change is thought to be one of the most pressing environmental problems facing humanity. However, due in part to failures in political communication and how the issue has been historically defined in American politics, discussions of climate change remain gridlocked and polarized. In this dissertation, I explore how climate change has been historically constructed as a political issue, how conflicts between climate advocates and skeptics have been communicated, and what effects polarization has had on political communication, particularly on the communication of climate change to skeptical audiences. I use a variety of methodological tools to consider these questions, including evolutionary frame analysis, which uses textual data to show how issues are framed and constructed over time; Kullback-Leibler divergence content analysis, which allows for comparison of advocate and skeptical framing over time; and experimental framing methods to test how audiences react to and process different presentations of climate change. I identify six major portrayals of climate change from 1988 to 2012, but find that no single construction of the issue has dominated the public discourse defining the problem. In addition, the construction of climate change may be associated with changes in public political sentiment, such as greater pessimism about climate action when the electorate becomes more conservative. As the issue of climate change has become more polarized in American politics, one proposed causal pathway for the observed polarization is that advocate and skeptic framing of climate change focuses on different facets of the issue and ignores rival arguments, a practice known as “talking past.” However, I find no evidence of increased talking past in 25 years of popular newsmedia reporting on the issue, suggesting both that talking past has not driven public polarization or that polarization is occurring in venues outside of the mainstream public discourse, such as blogs. To examine how polarization affects political communication on climate change, I test the cognitive processing of a variety of messages and sources that promote action against climate change among Republican individuals. Rather than identifying frames that are powerful enough to overcome polarization, I find that Republicans exhibit telltale signs of motivated skepticism on the issue, that is, they reject framing that runs counter to their party line and political identity. This result suggests that polarization constrains political communication on polarized issues, overshadowing traditional message and source effects of framing and increasing the difficulty communicators experience in reaching skeptical audiences.</p> / Dissertation

Almost twenty years after the signing of the United Nations Framework Convention on Climate Change and negotiations over mitigation and adaptation strategies to reduce greenhouse gas emissions began, the negotiations continue to fall short of scientific goals to curb warming. Current UNFCCC procedures do not provide for mediation in the process of negotiations. Public policy mediation has been used often at local, national, and regional levels to resolve environmental disputes. The characteristics of the climate change negotiations suggest that mediation may provide a number of benefits to the negotiations. Scholars and practitioners have developed criteria for determining the suitability of applying mediation to a dispute. The UNFCCC negotiations meet the majority of these criteria. However, the urgency of the issue, its complexity, the number of stakeholders, institutional capacity, and the power parity of the parties suggest mediation may be most beneficial if applied on a small scale at the UNFCCC negotiations. / 10000-01-01