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<p> Low coastal stratiform clouds (stratus, stratocumulus, and fog), referred to here as coastal low cloudiness (CLC), are a persistent seasonal feature of continental west coasts, including California. The importance of CLC ranges across fields, with applications ranging from solar resource forecasting, growth of endemic species, and heat wave expression and related health impacts. This dissertation improves our understanding of California&rsquo;s summertime CLC by describing its variability and influences on a range of scales from multidecadal to daily and continental to local. A novel achievement is the development of a new 19-year satellite-derived low cloud record. Trained on airport observations, this high resolution record plays a critical role in the description of CLC at finer spatial and shorter timescales. </p><p> Observations at coastal airports from Alaska to southern California reveal coherent interannual to interdecadal variation of CLC. The leading mode of CLC variability, accounting for nearly 40% of the total variance, and the majority of individual airports, exhibit decreasing low cloudiness from 1950 to 2012. The coherent patterns of CLC variability are organized by North Pacific Sea Surface Temperature (SST) anomalies, linked to the Pacific Decadal Oscillation (PDO). </p><p> The new satellite-derived low cloud retrieval reveals, in rich spatial texture, considerable variability in CLC within May-September. The average maximum cloudiness moves northward along the coast, from northern Baja, Mexico to northern California, from May to early August. Both component parts of lower tropospheric stability (LTS), SST and free-troposphere temperature, control this seasonal movement. The peak timing of cloudiness and daytime maximum temperatures are most closely aligned in northern California. </p><p> On weather timescales, daily CLC anomalies are most strongly related to stability anomalies to the north (climatologically upwind) of the CLC region. CLC is strongly linked to stability in northern (southern) California throughout (only in early) summer. Atmospheric rather than oceanic processes are responsible for the cloud dependence on stability at daily timescales. The spatial offset of the LTS-CLC relationship reveals the roles of advective processes, subsidence, and boundary layer characteristics. Free-tropospheric moisture additionally impacts CLC, implicating the North American monsoon as a factor affecting southern California&rsquo;s coastal climate in late summer.</p>

Abstract—This paper describes the application of the abrupt change detection technologies to detect the abrupt changes in the signals recorded during disturbances in the electrical power network of South Africa for disturbance analysis and relay performance monitoring. The aim is to estimate the time instants of the changes in the signal model parameters during the prefault condition, after initiation of fault, after the circuit-breaker opening and autoreclosure, etc. After these event-specific segmentations, the synchronization of the different digital fault recorder recordings are done based on the fault inception timings. The synchronized signals are segmented again. This synchronized segmentation is the first step toward automatic disturbance recognition, facilitating further complex feature vector analysis and pattern recognition. Besides, the synchronized, segmented recordings can be directly used to analyze certain kinds of disturbances and monitor the relay performance. This paper presents many practical examples from the power network in South Africa.

<p> This dissertation thesis details an interdisciplinary research project, which combines the strengths of resilience theory, the sustainable livelihood framework, complex systems theory, and modeling. These approaches are integrated to develop a tool that can help policy-makers make decisions under conditions of uncertainty, with the goals of reducing poverty and increasing environmental sustainability.</p><p> Achievement of the Millennium Development Goals, including reducing poverty and hunger, and increasing environmental sustainability, has been hampered due to global resource degradation and fluctuations in natural, social, political and financial systems. Climate change further impedes these goals, especially in developing countries. The resilience approach has been proposed to help populations adapt to climate change, but this abstract concept has been difficult to operationalize.</p><p> The sustainable livelihood framework has been used as a tool by development agencies to evaluate and eradicate poverty by finding linkages between livelihood and environment. However, critiques highlight its inability to handle large and cross-scale issues, like global climate change and environmental degradation. </p><p> Combining the sustainable livelihood framework and resilience theory will enhance the ability to simultaneously tackle the challenges of poverty eradication and climate change. However, real-life systems are difficult to understand and measure. A complex-systems approach enables improved understanding of real-life systems by recognizing nonlinearity, emergence, and self-organization. Nonetheless, this approach needs a framework to incorporate multiple dimensions, and an analytical technique.</p><p> This research project attempts to transform the concept of resilience into a measurable and operationally useful tool. It integrates resilience theory with the sustainable livelihood framework by using systems modeling techniques. As a case-study, it explores the resilience of household livelihoods within a local village <i>Panchayat</i> in central India.</p><p> This method integrated the 4-step cross-scale resilience approach with the sustainable livelihood framework through the use of a system dynamics modeling technique. Qualitative and quantitative data on social, economic and ecological variables was collected to construct a four-year panel at the panchayat scale. Socio-economic data was collected through questionnaires, focus group discussions, participant observation, and literature review. Ecological data on forest regeneration, degradation and growth rates was collected through sample plots, literature review of the region's forest management plans, and expert opinions, in the absence of data.</p><p> Using these data, a conceptual, bottom-up model, sensitive to local variability, was created and parameterized. The resultant model (tool), called the Livelihood Management System, is the first of its kind to use the system dynamics technique to model livelihood resilience.</p><p> Model simulations suggest that the current extraction rates of forest resources (non-timber forest produce, fuelwood and timber) are unsustainable. If continued, these will lead to increased forest degradation and decline in household income. Forest fires and grazing also have severe impacts on local forests, principally by retarding regeneration. The model suggests that protection from grazing and forest fires alone may significantly improve forest quality. Examining the dynamics of government-sponsored labor, model simulation suggests that it will be difficult to achieve the Government of India's goal of providing 100 days' wage labor per household through the National Rural Employment Guarantee Scheme.</p><p> Based on vulnerability analysis under the sustainable livelihood framework, eight risks to livelihoods were identified based on which six scenarios were created. One scenario was simulated to understand the resilience of local livelihoods to external shocks. Through these simulations, it was found that while climate change is a threat to local livelihoods, government policy changes have comparatively much larger impacts on local communities. The simulation demonstrates that reduced access to natural resources has significant impacts on local livelihoods. The simulation also demonstrates that reduced access drives forced migration, which increases the vulnerability of already risk-prone populations.</p><p> Through the development and simulation of the livelihood model, the research has been able to demonstrate a new methodology to operationalize resilience, indicating many promising next steps. Future undertakings in resilience analysis can allow for finding leverage points, thresholds and tipping points to help shift complex systems to desirable pathways and outcomes. Modeling resilience can help in identifying and prioritizing areas of intervention, and providing ways to monitor implementation progress, thus furthering the goals of reducing extreme poverty and hunger, and environmental sustainability.</p><p> Many challenges, such as high costs of data collection and the introduction of uncertainties, make model development and simulation harder. However, such challenges should be embraced as an integral part of complex analysis. In the long run, such analysis should become cost- and time-effective, contributing to data-driven decision-making processes, thus helping policy-makers take informed decisions under complex and uncertain conditions.</p>

This dissertation attempts to show how the study of the variations in demographic experience between different types of communities can advance the understanding of the processes of English population growth in the past, particularly during the period of rapid economic change in the eighteenth century. Attention is concentrated on an area of fifty-two parishes, centered around the border of North East Somerset and West Wiltshire, which contained communities involved in a variety of economic activities. The principal objective is to demonstrate the relationships between economic developments and demographic change and more especially to emphasize the inter-relatedness of events in different communities, each of which fits into a complex regional system. The process of investigation is in three stages: first, aggregated annual totals of baptisms, burials and marriages (taken from parish registers and related documents) are used to analyse the general chronology of population change in the area as a whole and explanations for the acceleration and timing of growth are discussed. Secondly, similarities in the experiences of the constituent communities are studied and these provide the basis for the definition ~f groups of parishes with common sets of attributes. Movements of people between these groups are found to be an important element of regional population change. And thirdly, more detailed analytical techniques are used to investigate the processes of population change within individual communities. This indicates significant spatial differences in the fertility of populations and a study of the persistency of families identifies to what extent these differences arose because of spatial variations in environmental and economic conditions or because of the redistribution of population. The overall conclusion is that population change in a particular place, at a particular time cannot be fully explained without an understanding of changes that took place in other parts of the region in earlier generations.

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<p> Previous studies investigating the velocity and elevation change records of the Greenland Ice Sheet (GrIS) revealed rapid and complex changes. It is therefore imperative to determine changes with both high spatial and temporal resolutions. By fusing multiple laser altimetry data sets, the Surface Elevation Reconstruction and Change (SERAC) program is capable of reconstructing surface elevation changes with high spatial and temporal resolution over the entire GrIS. The input data include observations from NASA&rsquo;s Ice, Cloud and land Elevation Satellite (ICESat) mission (2003-2009) as well as data collected by NASA&rsquo;s Airborne Topographic Mapper (ATM) (1993-2013) and Land, Vegetation and Ice Sensor (LVIS) (2007-2012) airborne laser altimetry systems. This study extends the record of surface elevation changes over the GrIS by adding 2012 and 2013 laser altimetry data to the previous 1993-2011 record. Extending the record leads to a new, more accurate and detailed altimetry record for 1993-2013. </p><p> Advanced Spaceborne Thermal Emission and Reflection Radiometer (ASTER) Digital Elevation Models (DEMs) are fused with laser altimetry data over Zachari&aelig; Isstr&oslash;m, northeast Greenland to analyze surface elevation changes and associated thinning rates during 1978-2014. Little to no elevation change occurred over Zachari&aelig; Isstr&oslash;m from 1978-1999, however, from 1999-2014 elevation changes near the calving front became increasingly negative and accelerated. Calving front position showed steady retreat and grounding line position has been retreating towards the interior of the ice sheet at an increasing rate from 2010-2014 when compared to the 1996-2010 period. The measured elevation changes near the calving front have brought a large portion of the glacier close to the height of flotation. If the current thinning trend continues this portion of the glacier will reach flotation within the next 2-5 years allowing for further retreat and increased vulnerability to retreat for sections of the glacier further upstream.</p>

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