scholarly journals The Impact of Anthropogenic Forcing and Natural Processes on Past, Present, and Future Rainfall over Victoria, Australia

2020 ◽  
Vol 33 (18) ◽  
pp. 8087-8106 ◽  
Author(s):  
Surendra P. Rauniyar ◽  
Scott B. Power
Keyword(s):  
Rainfall Variability ◽  
Internal Variability ◽  
First Century ◽  
External Forcing ◽  
Cool Season ◽  
Model Simulations ◽  
Millennium Drought ◽  
Twenty First Century ◽  
The Impact ◽  
Forced Drying

AbstractCool-season (April to October) rainfall dominates the annual average rainfall over Victoria, Australia, and is important for agriculture and replenishing reservoirs. Rainfall during the cool season has been unusually low since the beginning of the Millennium Drought in 1997 (~12% below the twentieth-century average). In this study, 24 CMIP5 climate models are used to estimate 1) the extent to which this drying is driven by external forcing and 2) future rainfall, taking both external forcing and internal natural climate variability into account. All models have preindustrial, historical, and twenty-first-century (RCP2.6, RCP4.5, and RCP8.5) simulations. It is found that rainfall in the past two decades is below the preindustrial average in two-thirds or more of model simulations. However, the magnitude of the multimodel median externally forced drying is equivalent to only 20% of the observed drying (interquartile range of 40% to −4%), suggesting that the drying is dominated by internally generated rainfall variability. Underestimation of internal variability of rainfall by the models, however, increases the uncertainties in these estimates. According to models the anthropogenically forced drying becomes dominant from 2010 to 2029, when drying is evident in over 90% of the model simulations. For the 2018–37 period, it is found that there is only a ~12% chance that internal rainfall variability could completely offset the anthropogenically forced drying. By the late twenty-first century, the anthropogenically forced drying under RCP8.5 is so large that internal variability appears too small to be able to offset it. Confidence in the projections is lowered because models have difficulty in simulating the magnitude of the observed decline in rainfall.

Relative Contribution of Anthropogenic Forcing and Natural Processes to Rainfall Variability over Victoria, Australia

2020 ◽  
Author(s):  
Surendra Rauniyar ◽  
Scott Power
Keyword(s):  
Climate Models ◽  
Global Climate ◽  
Rainfall Variability ◽  
Global Climate Models ◽  
Interquartile Range ◽  
Annual Rainfall ◽  
External Forcing ◽  
Cool Season ◽  
Millennium Drought ◽  
Forced Drying

<p>Victoria is the second-most populated and most densely populated state in Australia with a population of over 6.5 million. Over two thirds of the population live in greater Melbourne. It is also a major area for agriculture and tourism and is the second largest economy in Australia, accounting for a quarter of Australia's Gross Domestic Product. Any changes in Victoria's climate has huge impacts in these sectors. Rainfall over Victoria during the cool season (e.g. April to October) has been unusually low since the beginning of the Millennium Drought in 1997 (~12% below the 20<sup>th</sup> century average). Cool season rainfall contributes two-third to annual rainfall and is very important for many crops and for replenishing reservoirs across the state. Here we examine the extent to which this reduction in cool season rainfall is driven by external forcing, and the prospects for future multi-decadal rainfall, taking both external forcing and internal natural climate variability into account.</p><p>We analyse simulations from 40 global climate models from phase 5 of the Coupled Model Intercomparison Project (CMIP5) under preindustrial and historical forcing, as well as three scenarios for the 21<sup>st</sup> century: Representative Concentration Pathway (RCP)2.6, RCP4.5 and RCP8.5, which vary markedly in the amount of greenhouse gas emitted over the coming century. While the 1997-2018 average rainfall for cool season is below the preindustrial average in more than two-thirds of models under the three scenarios, the magnitude of the externally-forced drying is very small (median decline is around -2.5% in all three scenarios with an interquartile range around -5% to +1%). The model ensemble results suggest that external forcing contributed only 20% (interquartile range -41% to 4%) to the drying observed in 1997-2018, relative to 1900-1959. These results suggest that the observed drying was dominated by natural, internal rainfall variability. While the multi-model median is below average from 1997-2018 onwards, the externally-forced drying only becomes clear from 2010-2029, when the proportion of models exhibiting drying increases to over 90% under all three scenarios. This agreement reflects the increase in the magnitude of the externally-forced drying. We estimate that there is a 12% chance that internal rainfall variability will completely offset the externally-forced drying averaged over 2018-2037, regardless of scenario. By the late 21<sup>st</sup> century the externally forced change under RCP8.5 is so large that drying – even after taking internally variability into account - appears inevitable. </p><p>Confidence in the modelled projections is lowered because models have difficulty in simulating the magnitude of the observed decline in rainfall. Some of this difficulty appears to arise because most models seem to underestimate multidecadal rainfall variability. Other candidates are: the observed drying may have been primarily due to the occurrence of an extreme, internally-driven event; the models underestimate the magnitude of the externally-forced drying in recent decades; or some combination of the two. If externally-forced drying is underestimated because the response to greenhouse gases is underestimated then the magnitude of projected changes might also be underestimated.</p>

scholarly journals Changes in the Risk of Cool-Season Tornadoes over Southern Australia due to Model Projections of Anthropogenic Warming

2010 ◽  
Vol 23 (9) ◽  
pp. 2440-2449 ◽  
Author(s):  
B. Timbal ◽  
R. Kounkou ◽  
G. A. Mills
Keyword(s):  
Climate Change ◽  
Climate Models ◽  
Weather Prediction ◽  
First Century ◽  
Climate Projections ◽  
Cool Season ◽  
Near Surface ◽  
Impact Of Climate Change ◽  
Twenty First Century ◽  
The Impact

Abstract Anthropogenic climate change is likely to be felt most acutely through changes in the frequency of extreme meteorological events. However, quantifying the impact of climate change on these events is a challenge because the core of the climate change science relies on general circulation models to detail future climate projections, and many of these extreme events occur on small scales that are not resolved by climate models. This note describes an attempt to infer the impact of climate change on one particular type of extreme meteorological event—the cool-season tornadoes of southern Australia. The Australian Bureau of Meteorology predicts threat areas for cool-season tornadoes using fine-resolution numerical weather prediction model output to define areas where the buoyancy of a near-surface air parcel and the vertical wind shear each exceed specified thresholds. The diagnostic has been successfully adapted to coarser-resolution climate models and applied to simulations of the current climate, as well as future projections of the climate over southern Australia. Simulations of the late twentieth century are used to validate the models’ ability to reproduce the climatology of the risk of cool-season tornado formation by comparing these with similar computations based on historical reanalyses. Model biases are overcome by setting model specific thresholds to define the cool-season tornado risk. The diagnostic, applied to simulations of the twenty-first century, is then used to quantify the impact of the projected climate change on cool-season tornado risk. The sign of the response is consistent across all models: a decrease of the risk of formation during the twenty-first century is projected, driven by the thermodynamical response. The thermal response is modulated by the dynamical response, which varies between models. The projected decrease in tornadoes risk during the cool season is consistent with the projection of positive southern annular mode trends and the known influence of this mode of variability on interannual to intraseasonal time-scale variations in cool-season tornado occurrence.

Conclusion

2018 ◽  
Author(s):  
Emily Thomas
Keyword(s):  
Early Modern ◽  
First Century ◽  
Philosophical Theology ◽  
Time And Space ◽  
Modern Thought ◽  
Metaphysics Of Time ◽  
Twenty First Century ◽  
The Impact

This Conclusion draws the study to a close, and recounts its developmental theses. The first thesis is that the complexity of positions on time (and space) defended in early modern thought is hugely under-appreciated. An enormous variety of positions were defended during this period, going far beyond the well-known absolutism–relationism debate. The second thesis is that during this period three distinct kinds of absolutism can be found in British philosophy: Morean, Gassendist, and Newtonian. The chapter concludes with a few notes on the impact of absolutism within and beyond philosophy: on twenty-first-century metaphysics of time; and on art, geology, and philosophical theology.

scholarly journals A Twenty-First Century Guidebook for Applied Dynamical Systems

2006 ◽  
Vol 1 (4) ◽  
pp. 279-282 ◽  
Author(s):  
A. R. Champneys
Keyword(s):  
Dynamical Systems ◽  
21St Century ◽  
Vector Fields ◽  
Nonlinear Oscillations ◽  
First Century ◽  
Twenty First Century ◽  
The Impact ◽  
Young Researchers

This paper represents the author’s view on the impact of the book Nonlinear Oscillations, Dynamical Systems and Bifurcations of Vector Fields by John Guckenheimer and Philip Holmes, first published in 1983 (Springer-Verlag, Berlin). In particular, the questions addressed are: if one were to write a similar book for the 21st century, which topics should be contained and what form should the book take in order to have a similar impact on the modern generation of young researchers in applied dynamical systems?

Globalization, Nationalism, and Music Education in the Twenty-First Century in Greater China

2021 ◽  
Author(s):  
Wai-Chung Ho
Keyword(s):  
Music Education ◽  
Identity Formation ◽  
Cultural Values ◽  
Mainland China ◽  
Cultural Development ◽  
First Century ◽  
Greater China ◽  
Twenty First Century ◽  
China Mainland ◽  
The Impact

Globalization, Nationalism, and Music Education in the Twenty-First Century in Greater China examines the recent developments in school education and music education in Greater China – Mainland China, Hong Kong, and Taiwan – and the relationship between, and integration of, national cultural identity and globalization in their respective school curriculums. Regardless of their common history and cultural backgrounds, in recent decades, these localities have experienced divergent political, cultural, and educational structures. Through an analysis of the literature, official curriculum documents, approved music textbooks, and a survey questionnaire and in-depth interviews with music teachers, this book also examines the ways in which policies for national identity formation and globalization interact to complement and contradict each other in the context of music education in respect to national and cultural values in the three territories. Wai-Chung Ho’s substantive research interests include the sociology of music, China’s education system, and the comparative study of East Asian music education. Her research focuses on education and development, with an emphasis on the impact of the interplay between globalization, nationalization, and localization on cultural development and school music education.

scholarly journals The Impact of Climate Change on the Water Balance of Oil Sands Reclamation Covers and Natural Soil Profiles

2018 ◽  
Vol 19 (11) ◽  
pp. 1731-1752 ◽  
Author(s):  
Md. Shahabul Alam ◽  
S. Lee Barbour ◽  
Amin Elshorbagy ◽  
Mingbin Huang
Keyword(s):  
Oil Sands ◽  
Weather Generator ◽  
First Century ◽  
Soil Profiles ◽  
Percentage Increase ◽  
Climate Data ◽  
Historical Climate ◽  
Twenty First Century ◽  
The Impact

Abstract The design of reclamation soil covers at oil sands mines in northern Alberta, Canada, has been conventionally based on the calibration of soil–vegetation–atmosphere transfer (SVAT) models against field monitoring observations collected over several years, followed by simulations of long-term performance using historical climate data. This paper evaluates the long-term water balances for reclamation covers on two oil sands landforms and three natural coarse-textured forest soil profiles using both historical climate data and future climate projections. Twenty-first century daily precipitation and temperature data from CanESM2 were downscaled based on three representative concentration pathways (RCPs) employing a stochastic weather generator [Long Ashton Research Station Weather Generator (LARS-WG)]. Relative humidity, wind speed, and net radiation were downscaled using the delta change method. Downscaled precipitation and estimated potential evapotranspiration were used as inputs to simulate soil water dynamics using physically based models. Probability distributions of growing season (April–October) actual evapotranspiration (AET) and net percolation (NP) for the baseline and future periods show that AET and NP at all sites are expected to increase throughout the twenty-first century regardless of RCP, time period, and soil profile. Greater increases in AET and NP are projected toward the end of the twenty-first century. The increases in future NP at the two reclamation covers are larger (as a percentage increase) than at most of the natural sites. Increases in NP will result in greater water yield to surface water and may accelerate the rate at which chemical constituents contained within mine waste are released to downstream receptors, suggesting these potential changes need to be considered in mine closure designs.

scholarly journals The Impact of digitization on the religious sphere: televangelism as an example

2014 ◽  
Vol 4 (2) ◽  
pp. 189
Author(s):  
Shaimma El Naggar
Keyword(s):  
Social Media ◽  
Digital Media ◽  
First Century ◽  
Religious Expression ◽  
Media Technologies ◽  
Social Media Networks ◽  
Twenty First Century ◽  
Nuanced Understanding ◽  
Muslim Communities ◽  
The Impact

<p>Over the past few decades, televangelism has emerged as one important media phenomenon, inter alia, among Muslim communities. As a phenomenon, televangelism is interesting in many respects; it is a manifestation of the phenomenon of "info-tainment" as televangelists integrate entertainment features such as sound effects and music in their sermons. It is also a manifestation of the rise of the celebrity culture as televangelists have become 'media celebrities' with thousands of hundreds of fans and followers on social media networks.</p><p> </p><p>Thematically, this study is divided into two main sections. First. I delineate the characteristics of televangelism as a novel form of religious expression in which televangelists adopt a modern style and use colloquial language; and in which televangelists present religion as a source of individual change. I have argued that these features seem to have granted televangelists popularity particularly among Muslim youth who view televangelism as a new form of religious expression that is modern in appearance and relevant to their everyday lives.</p><p>The study has further highlighted the importance of digital media technologies in popularizing televangelists' programmes and sermons. Drawing on two case studies of popular televangelists, namely Amr Khaled and Hamza Yusuf, the study has shown that televangelists draw on a plethora of digital media tools to extend the visibility of their programmes including websites and social media networks. The study has found that televangelists' fans play an important role in popularizing televangelists' programmes. Moreover, the study relates televangelism to the rise of digital Islam. The study has argued that digitization and the increase of literacy rates have changed the structure of religious authority in the twenty first century, giving rise to new voices that are competing for authority. </p><p>Having provided an explanatory framework for the phenomenon of televangelism, the study moves in the second section to critique televangelism as an 'info-tainment' phenomenon.</p>Drawing on Carrette and King's <em>Selling Spirituality, </em>one issue that the study raises is the extent to which televangelism fits into the modern form of 'spiritualities'. Rather than being a critical reflection of the consumer culture, modern spiritualities seem to 'smooth out' resistance to the hegemony of capitalism and consumerism. I have proposed that it is through a content-related analysis of televangelists' sermons that one can get a nuanced understanding of how the discourses of particular televangelists can possibly relate to dominant (capitalist) ideologies, how structures of power are represented in their discourses and what their texts may reveal about the socio-historical contexts of Muslims in the twenty first century.

scholarly journals The early Spörer Minimum – a period of extraordinary climate and socio-economic changes in Western and Central Europe

2016 ◽  
Author(s):  
Chantal Camenisch ◽  
Kathrin M. Keller ◽  
Melanie Salvisberg ◽  
Benjamin Amann ◽  
Martin Bauch ◽  
...  
Keyword(s):  
Climate Variability ◽  
Central Europe ◽  
Climate Model ◽  
Internal Variability ◽  
Climatic Conditions ◽  
Food Prices ◽  
External Forcing ◽  
Adaptation Measures ◽  
Model Simulations ◽  
15Th Century

Abstract. Throughout the last millennium, mankind was affected by prolonged deviations from the climate mean state. While periods like the Maunder Minimum in the 17th century have been assessed in greater detail, earlier cold periods such as the 15th century received much less attention due to the sparse information available. Based on new evidence from different sources ranging from proxy archives to model simulations, it is now possible to provide an end-to-end assessment about the climate state during an exceptionally cold period in the 15th century, the role of internal, unforced climate variability and external forcing in shaping these extreme climatic conditions, and the impacts on and responses of the medieval society in Central Europe. Climate reconstructions from a multitude of natural and human archives indicate that, during winter, the period of the early Spörer Minimum (1431–1440 CE) was the coldest decade in Central Europe in the 15th century. The particularly cold winters and normal but wet summers resulted in a strong seasonal cycle that challenged food production and led to increasing food prices, a subsistence crisis, and a famine in parts of Europe. As a consequence, authorities implemented adaptation measures, such as the installation of grain storage capacities, in order to be prepared for future events. The 15th century is characterised by a grand solar minimum and enhanced volcanic activity, which both imply a reduction of seasonality. Climate model simulations show that periods with cold winters and strong seasonality are associated with internal climate variability rather than external forcing. Accordingly, it is hypothesised that the reconstructed extreme climatic conditions during this decade occurred by chance and in relation to the partly chaotic, internal variability within the climate system.

Introduction

2011 ◽  
pp. 1-11
Author(s):  
Brian Lehaney ◽  
Steve Clarke ◽  
Elayne Coakes ◽  
Gillian Jack
Keyword(s):  
Knowledge Management ◽  
First Century ◽  
Know How ◽  
Twenty First Century ◽  
The Impact ◽  
Easy Solution ◽  
The Way

If you want quick-fix solutions, this book is not for you. If you want to “dare to know” how to look at an organisation differently, harness the power of its knowledge, and create innovative and effective systems, then please read on! Knowledge management has been one of the most hyped phrases over the first years of the twenty-first century, and it has been mooted as the way forward for organisations to be dynamic, flexible, competitive, and successful. Despite the hype, and despite some individual successes, western economies and organisations may not have been greatly affected by this ‘all singing, all dancing’ solution to organisations’ problems. Has the impact of knowledge management been less than expected? If so, why? In order to address these questions, there are a number of others that must also be considered, such as: What is knowledge management? Why did it arise in the first place? Can it be simplified or categorised? Is it a fad? Is it theoretical? Is it practical? Why should I care about it? What can it do for my organisation? Does it provide a quick and easy solution?

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