This study focused on the reproductive response to elevated CO2 of plants possessing below-ground storage. I tested the hypotheses that under elevated CO2: (1) Plants with greater non-foliar storage capacity win show more reproductive response and (2) The altered foliar physiology of carbon (C) and nitrogen (N) use will cause increases in seed number and quality. Carbon dioxide treatments of High (650 muL L-1) and Ambient (360 muL L-1) were used in a controlled environment, simulated growing season, and in a natural pasture community. Hypothesis 1 was tested experimentally using four Raphanus varieties that differed in hypocotyl and leaf sizes. N fertilization and harvest times were used to obtain a range of root:shoot ratios. Enhancements in vegetative leaf area rather than the hypocotyl predicted reproductive responsiveness to CO 2. However, after three years of CO2 exposure in the pasture, hypocotyl-storing Taraxacum officinale responded strongly in vegetative biomass which correlated with inflorescence size and number. Fitness was enhanced four-fold, while the leaf-storing Plantago major produced more ramets and had only a two-fold fitness increase. Hypothesis 2 was tested by examining the C and N physiology underlying the vegetative organs and seeds of the pasture plants. Under elevated CO2, photosynthesis increased two-fold and senescence was delayed. Total plant C:N ratio did not differ, suggesting N acquisition increased. N similarly limited seed number in all cases suggesting an unchanged Physiology of N use in reproduction. While morphology constrained total biomass response, provisioning to seeds increased as shown by higher seed mass and number and decreased variability in number and mass. In all cases, leaf mass increase under high CO2 corresponded with fitness increase. Phenology constrained response to CO 2 as there was no plasticity in flowering day in Raphanus and Plantago, while there were flowering delays but greater seed maturation rate in Tar

National Geographic is a magazine that inspires people to care about the planet through its articles of exploration, education, and conservation. Magazines are a significant source of knowledge and compete with a variety of other media, constantly rethinking where they can improve in comparison to other media. Research in this dissertation shows that some magazines offer high quality imagery for artwork, photos and advertisements, which remains critical for industries and readers. They often offer greater depth than radio, TV, or even newspapers, so that people interested in an analysis of news and events still depend on magazines for informative and general news. People often turn to media—such as television, newspapers, magazines, radio, and Internet—to help them make sense of the many complexities relating to environmental science and governance that (un)consciously shape our lives. Global warming, as a subject, demands both political and personal responses in all parts of the world, and effective decision making at both scales depends on timely, accurate information, according to Shanahan (2009:145). The quality and quantity of journalism about climate change will therefore be key in the coming years. National Geographic comprises a variety of themes, such as environment, science, wildlife, travel and photography. This study is an analysis of the writing and photography related to one theme - global warming. It provides a critical analysis of the coverage of the global warming discourse in one magazine, examined over an eleven-year period from 2000 to 2010. This theme is powerful in that it represents ethical responsibility and concern for nature and our world and the analysis attempts to define the objects of discourse within the coverage, thus, evaluating if the format of the coverage informs and educates the audience about global warming.

Thesis (M.Sc. (Interdisciplinary Global Change Studies))--University of the Witwatersrand, Faculty of Science, School of Geography, Archaeology & Environmental Studies, 2017. / The objective of the thesis was to determine the relationship between climate variability and rural livelihoods in the Vhembe District Municipality situated in the extreme north of South Africa. These relationships ranged between food and nutritional security, land tenure, financial security, domestic politics and their impacts on human well-being in terms of the Sustainable Livelihoods Framework. The thesis uses a multi-discipline approach to assess the socio-economic outcomes of poor support to rural households that are struggling to attain an acceptable standard of living in the face of increasing challenges brought about by climate change. It also looked to investigate the capacity of rural households to adapt to the challenges of living in such an area. Results were obtained through questionnaires and basic interviews conducted among the residents of three selected areas in the Vhembe District of South Africa. The results demonstrate that residents of Vhembe go through daily suffering as a result of poor support and assistance in adapting to the challenges of climate change in the area and its impact on their livelihoods. The on-going academic literature suggests that integrated livelihood resilience is essential to adaptation to climate variability and that this can reduce the vulnerability of these areas. It also calls for the development and maintenance of effective local institutions supported by public private partnerships. Gaps identified in the literature suggested that more knowledge on land use change caused by seasonal variability as a result of the El Niño Southern Oscillation was needed as well as the prevalence of indigenous knowledge systems in adapting to these changes. It was found that local knowledge and effective local institutions were not as prevalent as expected in achieving livelihood adaptation. Some key findings were that 59% of households did not have access to arable land with 49% of respondents stating that they did not plant crops in the recent season due to the poor rains experienced. Furthermore, the reliance on social grants was notably high with 32% of respondents relying on these. Some residents who cannot pay to have access to electricity are forced to collect or buy firewood for everyday use. Furthermore, only 9% of respondents stated that they had access to flush toilets. These issues are shown to have environmental and other social consequences in the target communities. The thesis concludes that management of natural resources in Vhembe needs to be improved, as these are potential safety nets for the rural poor. It also suggests that there will need to be more support by government and business to set up beneficial agricultural projects to sustainably grow inclusive prosperity for rural residents of the Vhembe District. Key Words: Climate Variability, Sustainable Livelihood Framework, Adaptive Capacity / XL2018

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This study focuses on two main broad areas of active research on climate: climate variability and climate change and their implications on regional precipitation characteristics. All the analysis is carried out for a climate change-sensitive region, the state of Florida, USA. The focus of the climate variability analysis is to evaluate the influence of individual and coupled phases (cool and warm) of Atlantic multidecadal oscillation (AMO) and El Niäno southern oscillation (ENSO) on regional precipitation characteristics. The two oscillations in cool and warm phases modulate each other which have implications on flood control and water supply in the region. Extreme precipitation indices, temporal distribution of rainfall within extreme storm events, dry and wet spell transitions and antecedent conditions preceding extremes are evaluated. Kernel density estimates using Gaussian kernel for distribution-free comparative analysis and bootstrap sampling-based confidence intervals are used to compare warm and cool phases of different lengths. Depth-duration-frequency (DDF) curves are also developed using generalized extreme value (GEV) distributions characterizing the extremes. ... This study also introduces new approaches to optimally select the predictor variables which help in modeling regional precipitation and further provides a mechanism to select an optimum spatial resolution to downscale the precipitation projections. New methods for correcting the biases in monthly downscaled precipitation projections are proposed, developed and evaluated in this study. The methods include bias corrections in an optimization framework using various objective functions, hybrid methods based on universal function approximation and new variants. / by Aneesh Goly. / Thesis (Ph.D.)--Florida Atlantic University, 2013. / Includes bibliography. / Mode of access: World Wide Web. / System requirements: Adobe Reader.

Monthly water balance models are important tools for hydrological impact assessment of climate change. Traditionally monthly models adopt a conceptual, lumped-parameter approach. Based on an extensive survey and review of existing monthly water balance models, six models with different conceptualization and structure, i.e., Thomthwaite-Mather, Belgium, Xinanjiang, Guo, WatBal and Schaake, were compared through calibration and validation using observed data of hydrology and climate of 1960-1988 in the Dongjiang basin. The model comparison offered insights for the development of a monthly distributed model which integrates the spatial variations of basin terrain and rainfall into runoff simulation. An innovative feature of the new model is that the spatial distribution of soil moisture capacity which is described as a parabolic curve in Xinanjiang model is represented by a cumulative frequency curve of index of relative difficulty of runoff generation based on the concept of topographic index in TOPMODEL. The calibration and validation results show that the developed model with only three parameters is suitable for monthly runoff simulation in the Dongjiang basin. / The developed model was applied to evaluate the changes in water availability in the Dongjiang basin under hypothetical climate change scenarios and those derived from projections of three General Circulation Models (GCM), i.e., CGCM1, CSIRO and ECHAM4. Sensitivity analyses based on hypothetical scenarios suggest that climatic change has greater effects on runoff than on soil moisture and greater effects on water availability in dry months than in wet months. The effects of precipitation changes on the amount of runoff and soil moisture can be characterized by a magnification factor whereas temperature increases alone produce negligible effects. Hydrological simulation with inputs of three GCM-generated scenarios indicates that annual and rain-season runoff will increase by 0.3°io to 13.9% and 7.6% to 12.0%, respectively, by the 2050s. Dry-season runoff will change between -23.2% and +26.4%. Average annual and dry-season soil moisture will decrease by 1.3% to 6.9% and 1.0% to 8.1%, respectively. Soil moisture will demonstrate little change in rain-season. Increase in annual runoff and reduction in annual soil moisture will be apparent over the whole basin, but there is relatively little consistency among the three GCM-generated scenarios as to the magnitudes of spatial change in runoff and soil moisture. Although these results are not definitive statements as to what will happen to runoff and soil moisture in the Dongjiang basin, they rather have significant implications for the study of response strategies of water supply and flood control to climate change. / Jiang Tao. / "July 2005." / Advisers: Chen Yongqin; Lam Kin-che. / Source: Dissertation Abstracts International, Volume: 67-01, Section: B, page: 0149. / Thesis (Ph.D.)--Chinese University of Hong Kong, 2005. / Includes bibliographical references (p. 174-190). / Electronic reproduction. Hong Kong : Chinese University of Hong Kong, [2012] System requirements: Adobe Acrobat Reader. Available via World Wide Web. / Electronic reproduction. [Ann Arbor, MI] : ProQuest Information and Learning, [200-] System requirements: Adobe Acrobat Reader. Available via World Wide Web. / Electronic reproduction. Ann Arbor, MI : ProQuest Information and Learning Company, [200-] System requirements: Adobe Acrobat Reader. Available via World Wide Web. / School code: 1307.

Water management plans are typically developed using historical data records and historical return periods for extreme events, such as floods or droughts. Since these analyses of return periods typically assume a certain degree of stationarity (constant mean, standard deviation, distribution) in hydrologic variables, the potential future impacts of climate change are excluded. In developing water management plans, predicted changes to climate variables should be considered to evaluate the degree of non-stationarity that may exist in the future. In this way, regions most sensitive to climate change can be identified and managed appropriately. This study performed such a task by using predicted climate data that were downscaled from general circulation models (GCM) by regional climate models (RCM) to compare climate variables in the historical period of 1971-1998 to the future period of 2041-2068. The study evaluated the precipitation and minimum/maximum temperature data from five different GCM/RCM combinations: 1) CCSM/CRCM; 2) CCSM/WRFG; 3) CGCM3/CRCM; 4) CGCM3/WRFG; and 5) HadCM3/HRM3. The five datasets were then used to calculate drought indices and drive a calibrated PRMS model of the Molalla Pudding river basin in order to evaluate changes in droughts and streamflow. The predicted changes in droughts and streamflow were then evaluated with social/economic factors for twelve cities in the Molalla Pudding river basin by two different water vulnerability indices. The index values were used to determine a rank for each city that indicated its relative vulnerability to water scarcity as compared to the other cities. In this study, three out of the five datasets predicted increased precipitation (+97-115 mm/year) over the Molalla Pudding basin and the two datasets using the CCSM GCM data predicted either no change or slightly decreased precipitation (-60 mm/year) over the Molalla Pudding basin in 2041-2068. All datasets predicted increased minimum and maximum average temperature of +1.5°C and +1.4°C respectively, and all datasets displayed increasing trends in temperature. The drought indices predicted fewer drought events (-2.4 events) over 2041-2068 with no change in duration, and no change to the number of serious drought events over 2041-2068 but with increased durations (+1.9 months). Results from the hydrologic modeling predicted increased streamflow (+4-249 cfs) in four out of the five future datasets. Using the predicted changes in hydrologic variables and social/economic census data from 2000, two types of water vulnerability indices were calculated for the twelve cities of interest. The results suggested that cities in the western portion of the basin would be more susceptible to current and future water vulnerability due to high irrigation demands for water and high social vulnerability as determined by minority populations and higher poverty, while the small cities with less dependence on agriculture would be less vulnerable.

Spatial and temporal interpolation methods are commonly used methods for estimating missing precipitation rain gauge data based on values recorded at neighboring gauges. However, these interpolation methods have not been comprehensively checked for their ability to preserve time series characteristics. Assessing the preservation of time series characteristics helps achieving a threshold criteria of length of gaps in a data set that is acceptable to be filled. This study evaluates the efficacy of optimal weighting interpolation for estimation of missing data in preserving time series characteristics. Rain gauges in the state of Kentucky are used as a case study. Several model performance measures are also evaluated to validate the filling model; followed by time series characteristics to evaluate the accuracy of estimation and preservation of precipitation data characteristics. This study resulted in a definition of region-specific threshold of the maximum length of gaps allowed in a data set at five percent. / Includes bibliography. / Thesis (M.S.)--Florida Atlantic University, 2016. / FAU Electronic Theses and Dissertations Collection