Paull Nunez
- Published in print:
- 2010
- Published Online:
- May 2010
- ISBN:
- 9780195340716
- eISBN:
- 9780199776269
- Item type:
- chapter
- Publisher:
- Oxford University Press
- DOI:
- 10.1093/acprof:oso/9780195340716.003.0012
- Subject:
- Neuroscience, Development
This chapter takes a highly speculative approach in which the hard problem of consciousness is approached with questions about a category beyond ordinary information; that is, Ultra-Information, ...
More
This chapter takes a highly speculative approach in which the hard problem of consciousness is approached with questions about a category beyond ordinary information; that is, Ultra-Information, defined broadly to include ordinary information, unknown physical processes, and consciousness. Thoughts, emotions, self-awareness, memory, and the contents of the unconscious are, by definition, categories of Ultra-Information, whether or not these mental processes also involve ordinary information.Less
This chapter takes a highly speculative approach in which the hard problem of consciousness is approached with questions about a category beyond ordinary information; that is, Ultra-Information, defined broadly to include ordinary information, unknown physical processes, and consciousness. Thoughts, emotions, self-awareness, memory, and the contents of the unconscious are, by definition, categories of Ultra-Information, whether or not these mental processes also involve ordinary information.
Brad de Young, Francisco E. Werner, Harold Batchelder, François Carlotti, Øyvind Fiksen, Eileen E. Hofmann, Suam Kim, Michio J. Kishi, and Hidekatsu Yamazaki
- Published in print:
- 2010
- Published Online:
- May 2010
- ISBN:
- 9780199558025
- eISBN:
- 9780191721939
- Item type:
- chapter
- Publisher:
- Oxford University Press
- DOI:
- 10.1093/acprof:oso/9780199558025.003.0005
- Subject:
- Biology, Biodiversity / Conservation Biology, Aquatic Biology
GLOBEC studies have greatly expanded our understanding of the structure and functioning of marine ecosystems, in particular demonstrating the importance of life history dynamics in determining the ...
More
GLOBEC studies have greatly expanded our understanding of the structure and functioning of marine ecosystems, in particular demonstrating the importance of life history dynamics in determining the influence of physical processes on organisms in the ocean. The linkages between physical and biological processes were explored through novel approaches to experimentation in the laboratory, in the field, and through biophysical models of the coupled dynamics. New observations and the development of realistic physical circulation models have made it possible to quantitatively explore the relation between advection by large‐scale hydrodynamic fields, motions of actively behaving organisms at the scale of the individuals, and the response of organisms to dynamically evolving predator—prey fields. Scale dependence has also been demonstrated through observations that cover a wide geographic range and models that allow high resolution ranging from continental shelf to oceanic basin scales. The complexity of the interactions in marine ecosystems has required consideration of as many factors as possible while at the same time focusing on the primary factors, given the challenges of disentangling the complexity. These ideas and approaches to biophysical coupling are reviewed through presentation of the research that has been carried out during the GLOBEC programme over the past two decades.Less
GLOBEC studies have greatly expanded our understanding of the structure and functioning of marine ecosystems, in particular demonstrating the importance of life history dynamics in determining the influence of physical processes on organisms in the ocean. The linkages between physical and biological processes were explored through novel approaches to experimentation in the laboratory, in the field, and through biophysical models of the coupled dynamics. New observations and the development of realistic physical circulation models have made it possible to quantitatively explore the relation between advection by large‐scale hydrodynamic fields, motions of actively behaving organisms at the scale of the individuals, and the response of organisms to dynamically evolving predator—prey fields. Scale dependence has also been demonstrated through observations that cover a wide geographic range and models that allow high resolution ranging from continental shelf to oceanic basin scales. The complexity of the interactions in marine ecosystems has required consideration of as many factors as possible while at the same time focusing on the primary factors, given the challenges of disentangling the complexity. These ideas and approaches to biophysical coupling are reviewed through presentation of the research that has been carried out during the GLOBEC programme over the past two decades.
Mark Tatham and Katherine Morton
- Published in print:
- 2003
- Published Online:
- September 2007
- ISBN:
- 9780199250677
- eISBN:
- 9780191719462
- Item type:
- chapter
- Publisher:
- Oxford University Press
- DOI:
- 10.1093/acprof:oso/9780199250677.003.0017
- Subject:
- Linguistics, Phonetics / Phonology
This chapter proposes a speech production architecture in which all speech occurs within two larger frameworks called wrappers. The overall wrapper is expression; the next wrapper is prosody. ...
More
This chapter proposes a speech production architecture in which all speech occurs within two larger frameworks called wrappers. The overall wrapper is expression; the next wrapper is prosody. Expression and prosody are defined as used in this book. Within a prosodic framework, planning and rendering (carrying out the plan to speak by moving the articulators) is presented. Cognitive and physical processes and their phonological and phonetic correlates are discussed.Less
This chapter proposes a speech production architecture in which all speech occurs within two larger frameworks called wrappers. The overall wrapper is expression; the next wrapper is prosody. Expression and prosody are defined as used in this book. Within a prosodic framework, planning and rendering (carrying out the plan to speak by moving the articulators) is presented. Cognitive and physical processes and their phonological and phonetic correlates are discussed.
David J. Chalmers
- Published in print:
- 2010
- Published Online:
- January 2011
- ISBN:
- 9780195311105
- eISBN:
- 9780199870851
- Item type:
- chapter
- Publisher:
- Oxford University Press
- DOI:
- 10.1093/acprof:oso/9780195311105.003.0010
- Subject:
- Philosophy, Philosophy of Mind
Confronted with the apparent explanatory gap between physical processes and consciousness, philosophers have reacted in many different ways. Some deny that any explanatory gap exists at all. Some ...
More
Confronted with the apparent explanatory gap between physical processes and consciousness, philosophers have reacted in many different ways. Some deny that any explanatory gap exists at all. Some hold that there is an explanatory gap for now but that it will eventually be closed. Some hold that the explanatory gap corresponds to an ontological gap in nature. This chapter explores another reaction to the explanatory gap. Those who react in this way agree that there is an explanatory gap, but they hold that it stems from the way we think about consciousness. In particular, this view locates the gap in the relationship between our concepts of physical processes and our concepts of consciousness, rather than in the relationship between physical processes and consciousness themselves.Less
Confronted with the apparent explanatory gap between physical processes and consciousness, philosophers have reacted in many different ways. Some deny that any explanatory gap exists at all. Some hold that there is an explanatory gap for now but that it will eventually be closed. Some hold that the explanatory gap corresponds to an ontological gap in nature. This chapter explores another reaction to the explanatory gap. Those who react in this way agree that there is an explanatory gap, but they hold that it stems from the way we think about consciousness. In particular, this view locates the gap in the relationship between our concepts of physical processes and our concepts of consciousness, rather than in the relationship between physical processes and consciousness themselves.
Geir Ottersen, Nils Chr. Stenseth, and James W. Hurrell
- Published in print:
- 2005
- Published Online:
- September 2007
- ISBN:
- 9780198507499
- eISBN:
- 9780191709845
- Item type:
- chapter
- Publisher:
- Oxford University Press
- DOI:
- 10.1093/acprof:oso/9780198507499.003.0001
- Subject:
- Biology, Aquatic Biology
This introductory chapter begins with a brief account of the Atlantic as a whole and how it is linked to other oceans, before focusing on the main currents and hydrography of the North Atlantic. This ...
More
This introductory chapter begins with a brief account of the Atlantic as a whole and how it is linked to other oceans, before focusing on the main currents and hydrography of the North Atlantic. This is followed by a brief account of some of the main circulation patterns in the world's oceans and the role of large-scale climate variability. It provides an overview of oceanographic processes that are believed to be of particular importance to marine ecology. Finally, examples are presented to illustrate how diverse the responses of ecology are to atmospheric and ocean climate variability.Less
This introductory chapter begins with a brief account of the Atlantic as a whole and how it is linked to other oceans, before focusing on the main currents and hydrography of the North Atlantic. This is followed by a brief account of some of the main circulation patterns in the world's oceans and the role of large-scale climate variability. It provides an overview of oceanographic processes that are believed to be of particular importance to marine ecology. Finally, examples are presented to illustrate how diverse the responses of ecology are to atmospheric and ocean climate variability.
Joanna D. Haigh and Peter Cargill
- Published in print:
- 2015
- Published Online:
- October 2017
- ISBN:
- 9780691153834
- eISBN:
- 9781400866540
- Item type:
- chapter
- Publisher:
- Princeton University Press
- DOI:
- 10.23943/princeton/9780691153834.003.0009
- Subject:
- Environmental Science, Climate
This concluding chapter talks about how the Earth's climate is fundamental to the well-being of humanity, and any factor with the potential to affect that is obviously of concern. Thus, an ...
More
This concluding chapter talks about how the Earth's climate is fundamental to the well-being of humanity, and any factor with the potential to affect that is obviously of concern. Thus, an understandable interest in the body that provides the energy for all life on Earth has driven a long history of study of how changes in the Sun might influence the climate. The wealth of physical, chemical, and biological processes involved also makes the topic of intrinsic scientific fascination. Observations of the Sun, alongside theoretical advances and developments in models, are helping to further understanding of its behavior. In particular, significant advances have been made in determining how different activity indicators relate to the physical processes involved in the evolution of the solar magnetic field, sunspots, and radiation over the 11-year cycle.Less
This concluding chapter talks about how the Earth's climate is fundamental to the well-being of humanity, and any factor with the potential to affect that is obviously of concern. Thus, an understandable interest in the body that provides the energy for all life on Earth has driven a long history of study of how changes in the Sun might influence the climate. The wealth of physical, chemical, and biological processes involved also makes the topic of intrinsic scientific fascination. Observations of the Sun, alongside theoretical advances and developments in models, are helping to further understanding of its behavior. In particular, significant advances have been made in determining how different activity indicators relate to the physical processes involved in the evolution of the solar magnetic field, sunspots, and radiation over the 11-year cycle.
Melissa Hines
- Published in print:
- 2005
- Published Online:
- May 2009
- ISBN:
- 9780195188363
- eISBN:
- 9780199865246
- Item type:
- chapter
- Publisher:
- Oxford University Press
- DOI:
- 10.1093/acprof:oso/9780195188363.003.0002
- Subject:
- Neuroscience, Neuroendocrine and Autonomic, Development
This chapter discusses the processes that are involved in physical sexual differentiation. Topics covered include mechanisms of sexual differentiation, how hormones control sexual development, human ...
More
This chapter discusses the processes that are involved in physical sexual differentiation. Topics covered include mechanisms of sexual differentiation, how hormones control sexual development, human sexual development, and the causes of intersex syndromes.Less
This chapter discusses the processes that are involved in physical sexual differentiation. Topics covered include mechanisms of sexual differentiation, how hormones control sexual development, human sexual development, and the causes of intersex syndromes.
Wesley C. Salmon
- Published in print:
- 1998
- Published Online:
- November 2003
- ISBN:
- 9780195108644
- eISBN:
- 9780199833627
- Item type:
- chapter
- Publisher:
- Oxford University Press
- DOI:
- 10.1093/0195108647.003.0015
- Subject:
- Philosophy, Philosophy of Science
Provides a critical analysis and comparison of the theories of probabilistic causality offered by Hans Reichenbach I.J. Good and Patrick Suppes. Each of these theories faces some fundamental ...
More
Provides a critical analysis and comparison of the theories of probabilistic causality offered by Hans Reichenbach I.J. Good and Patrick Suppes. Each of these theories faces some fundamental difficulties. In the end, the author argues that probabilistic causality cannot be explicated in terms of statistical relations among discrete events alone. Instead, we must take into account the physical processes that provide causal connections among events. In the time since this essay was first written, the literature on probabilistic causality has burgeoned, and the topic has become a major area of concern to many philosophers.Less
Provides a critical analysis and comparison of the theories of probabilistic causality offered by Hans Reichenbach I.J. Good and Patrick Suppes. Each of these theories faces some fundamental difficulties. In the end, the author argues that probabilistic causality cannot be explicated in terms of statistical relations among discrete events alone. Instead, we must take into account the physical processes that provide causal connections among events. In the time since this essay was first written, the literature on probabilistic causality has burgeoned, and the topic has become a major area of concern to many philosophers.
J. David Pleins
- Published in print:
- 2009
- Published Online:
- October 2011
- ISBN:
- 9780199733637
- eISBN:
- 9780199852505
- Item type:
- chapter
- Publisher:
- Oxford University Press
- DOI:
- 10.1093/acprof:oso/9780199733637.003.0005
- Subject:
- Religion, Biblical Studies
Various endeavors were made to make logical sense out of the story of Noah's ark even before the fundamentalist movement was set in motion. Although several Christian and Jewish interpreters ...
More
Various endeavors were made to make logical sense out of the story of Noah's ark even before the fundamentalist movement was set in motion. Although several Christian and Jewish interpreters attempted to exaggerate certain aspects of the story to find moral guidance and spiritual insight, scientific thinkers during the 16th and 17th centuries tried coming up with stories that would seem rational in the context of looking into certain mechanical theories regarding the history and physical processes of the earth. Further developments of these theories during the 18th and 19th centuries have considered the possibility of relating geological sciences and fossil studies with the narrative about the flood. Consequently, these actions have presented new approaches in examining the narratives of the Bible as a work that advocates s humanistic importance.Less
Various endeavors were made to make logical sense out of the story of Noah's ark even before the fundamentalist movement was set in motion. Although several Christian and Jewish interpreters attempted to exaggerate certain aspects of the story to find moral guidance and spiritual insight, scientific thinkers during the 16th and 17th centuries tried coming up with stories that would seem rational in the context of looking into certain mechanical theories regarding the history and physical processes of the earth. Further developments of these theories during the 18th and 19th centuries have considered the possibility of relating geological sciences and fossil studies with the narrative about the flood. Consequently, these actions have presented new approaches in examining the narratives of the Bible as a work that advocates s humanistic importance.
John E. Mayfield
- Published in print:
- 2013
- Published Online:
- November 2015
- ISBN:
- 9780231163040
- eISBN:
- 9780231535281
- Item type:
- chapter
- Publisher:
- Columbia University Press
- DOI:
- 10.7312/columbia/9780231163040.003.0002
- Subject:
- Biology, Evolutionary Biology / Genetics
Computers are machines that manipulate information, and computer science is the formal discipline that studies limitations and opportunities afforded by this type of activity. This chapter explores ...
More
Computers are machines that manipulate information, and computer science is the formal discipline that studies limitations and opportunities afforded by this type of activity. This chapter explores the nature of computation and the relationships that exist between computation, physical process, and the formation of structure. It attempts to convince the reader that the notion of computation is more general than simply what happens in electronic computers and that it is not possible to cleanly separate many kinds of physical activity from computation. A convenient way to understand the notion of computation is to see every computation as a process in which a pattern interfaces with a device in such a way that a series of changes occurs within the device, culminating in output. The output may be useful in ways that the input is not. This raises several questions: What does it mean to manipulate information? Is information preserved during a computation? Where does new information come from? What are the minimum requirements for a computer to be able to “manipulate information”?Less
Computers are machines that manipulate information, and computer science is the formal discipline that studies limitations and opportunities afforded by this type of activity. This chapter explores the nature of computation and the relationships that exist between computation, physical process, and the formation of structure. It attempts to convince the reader that the notion of computation is more general than simply what happens in electronic computers and that it is not possible to cleanly separate many kinds of physical activity from computation. A convenient way to understand the notion of computation is to see every computation as a process in which a pattern interfaces with a device in such a way that a series of changes occurs within the device, culminating in output. The output may be useful in ways that the input is not. This raises several questions: What does it mean to manipulate information? Is information preserved during a computation? Where does new information come from? What are the minimum requirements for a computer to be able to “manipulate information”?
John Bolender
- Published in print:
- 2010
- Published Online:
- August 2013
- ISBN:
- 9780262014441
- eISBN:
- 9780262289238
- Item type:
- chapter
- Publisher:
- The MIT Press
- DOI:
- 10.7551/mitpress/9780262014441.003.0001
- Subject:
- Neuroscience, Research and Theory
This chapter demonstrates that there are deep necessities in how social relations are conceived. It illustrates that there are some very central aspects of relational cognition that are deeply ...
More
This chapter demonstrates that there are deep necessities in how social relations are conceived. It illustrates that there are some very central aspects of relational cognition that are deeply necessary. In some of its central aspects, the structuring of the social mind is more like the formation of a snowflake crystal than the evolution of the middle ear or the eye. This chapter shows that there is a profound link between mental and physical processes, including inorganic ones.Less
This chapter demonstrates that there are deep necessities in how social relations are conceived. It illustrates that there are some very central aspects of relational cognition that are deeply necessary. In some of its central aspects, the structuring of the social mind is more like the formation of a snowflake crystal than the evolution of the middle ear or the eye. This chapter shows that there is a profound link between mental and physical processes, including inorganic ones.
Erik Swyngedouw
- Published in print:
- 2004
- Published Online:
- November 2020
- ISBN:
- 9780198233916
- eISBN:
- 9780191916519
- Item type:
- chapter
- Publisher:
- Oxford University Press
- DOI:
- 10.1093/oso/9780198233916.003.0012
- Subject:
- Earth Sciences and Geography, Social and Political Geography
In recent years, we have become increasingly aware of the importance of water as a critical good, and questions of water supply, access, and management, both in quantitative and qualitative terms, ...
More
In recent years, we have become increasingly aware of the importance of water as a critical good, and questions of water supply, access, and management, both in quantitative and qualitative terms, have become key issues (Gleick 1993; Postel 1992; Stauffer 1998). The proliferating commodification and privatization of water management systems; the combination of Global Environmental Change with increased demands from cities, agriculture, and industry for reasonably clean water; the inadequate access of almost a billion people on the planet to clean water (over half of whom live in large urban centres); the proliferating geopolitical struggle over the control of river basins; the popular resistance against the construction of new megadams; the political struggles around water privatization projects; and many other issues; have brought water politics to the foreground of national and international agendas (Shiklomanov 1990; 1997; Herrington 1996; Roy 2001). In the twentieth century, water scarcity was seen as a problem primarily affecting developing societies (Anton 1993). However, at the turn of the new century, water problems are becoming increasingly globalized. In Europe, the area bordering the Mediterranean, notably Spain, southern Italy, and Greece, is arguably the location in which the water crisis has become most acute, both in quantitative and qualitative terms (Batisse and Gernon 1989; Margat 1992; Swyngedouw 1996a). However, northern European countries, such as the UK, Belgium, and France, have also seen increasing problems with water supply, water management, and water control (Haughton 1996), while transitional societies in eastern Europe are faced with mounting water supply problems (Thomas and Howlett 1993). The Yorkshire drought in England, for example, or the Walloon/Flemish dispute over water rights are illuminating examples of the intensifying conflict that surrounds water issues (Bakker 1999). Cities in the global South and the global North alike are suffering from a deterioration in their water supply infrastructure and in their environmental and social conditions in general (Lorrain 1995; Brockerhoff and Brennan 1998). Up to 50% of urban residents in the developing world’s megacities have no easy access to reasonably clean and affordable water. The myriad socioenvironmental problems associated with deficient water supply conditions threaten urban sustainability, social cohesion, and, most disturbingly, the livelihoods of millions of people (Niemczynowicz 1991).
Less
In recent years, we have become increasingly aware of the importance of water as a critical good, and questions of water supply, access, and management, both in quantitative and qualitative terms, have become key issues (Gleick 1993; Postel 1992; Stauffer 1998). The proliferating commodification and privatization of water management systems; the combination of Global Environmental Change with increased demands from cities, agriculture, and industry for reasonably clean water; the inadequate access of almost a billion people on the planet to clean water (over half of whom live in large urban centres); the proliferating geopolitical struggle over the control of river basins; the popular resistance against the construction of new megadams; the political struggles around water privatization projects; and many other issues; have brought water politics to the foreground of national and international agendas (Shiklomanov 1990; 1997; Herrington 1996; Roy 2001). In the twentieth century, water scarcity was seen as a problem primarily affecting developing societies (Anton 1993). However, at the turn of the new century, water problems are becoming increasingly globalized. In Europe, the area bordering the Mediterranean, notably Spain, southern Italy, and Greece, is arguably the location in which the water crisis has become most acute, both in quantitative and qualitative terms (Batisse and Gernon 1989; Margat 1992; Swyngedouw 1996a). However, northern European countries, such as the UK, Belgium, and France, have also seen increasing problems with water supply, water management, and water control (Haughton 1996), while transitional societies in eastern Europe are faced with mounting water supply problems (Thomas and Howlett 1993). The Yorkshire drought in England, for example, or the Walloon/Flemish dispute over water rights are illuminating examples of the intensifying conflict that surrounds water issues (Bakker 1999). Cities in the global South and the global North alike are suffering from a deterioration in their water supply infrastructure and in their environmental and social conditions in general (Lorrain 1995; Brockerhoff and Brennan 1998). Up to 50% of urban residents in the developing world’s megacities have no easy access to reasonably clean and affordable water. The myriad socioenvironmental problems associated with deficient water supply conditions threaten urban sustainability, social cohesion, and, most disturbingly, the livelihoods of millions of people (Niemczynowicz 1991).
Stephen Wolfram
- Published in print:
- 2008
- Published Online:
- August 2013
- ISBN:
- 9780262026215
- eISBN:
- 9780262268011
- Item type:
- chapter
- Publisher:
- The MIT Press
- DOI:
- 10.7551/mitpress/9780262026215.003.0025
- Subject:
- Philosophy, Philosophy of Science
This chapter explores some fundamental consequences of the correspondence between physical process and computations. Most physical questions may be answerable only through irreducible amounts of ...
More
This chapter explores some fundamental consequences of the correspondence between physical process and computations. Most physical questions may be answerable only through irreducible amounts of computation. Those that concern idealized limits of infinite time, volume, or numerical precision can require arbitrarily long computations, and so be considered formally undecidable. The behavior of a physical system may always be calculated by simulating explicitly each step in its evolution. Much of theoretical physics has, however, been concerned with devising shorter methods of calculation that reproduce the outcome without tracing each step. Computational irreducibility is common among the systems investigated in mathematics and computation theory, but it may well be the exception rather than the rule, since most physical questions may be answerable only through irreducible amounts of computation.Less
This chapter explores some fundamental consequences of the correspondence between physical process and computations. Most physical questions may be answerable only through irreducible amounts of computation. Those that concern idealized limits of infinite time, volume, or numerical precision can require arbitrarily long computations, and so be considered formally undecidable. The behavior of a physical system may always be calculated by simulating explicitly each step in its evolution. Much of theoretical physics has, however, been concerned with devising shorter methods of calculation that reproduce the outcome without tracing each step. Computational irreducibility is common among the systems investigated in mathematics and computation theory, but it may well be the exception rather than the rule, since most physical questions may be answerable only through irreducible amounts of computation.
Dieter Helm
- Published in print:
- 2012
- Published Online:
- October 2013
- ISBN:
- 9780300186598
- eISBN:
- 9780300188646
- Item type:
- chapter
- Publisher:
- Yale University Press
- DOI:
- 10.12987/yale/9780300186598.003.0002
- Subject:
- Environmental Science, Environmental Studies
This chapter examines the importance of climate change and its underlying physical processes, and the impact of various degrees of warming on human civilization. The seminars at environment and ...
More
This chapter examines the importance of climate change and its underlying physical processes, and the impact of various degrees of warming on human civilization. The seminars at environment and climate change institutes and departments invite in the campaigners, blurring the boundaries between impartial academic research and partial and committed interests. The climate has always been changing, and within human history there have been substantial swings in global and regional temperatures. Longer growing seasons and milder winters mean that the constraints on economic activities in the cold places (and the costs) are somewhat alleviated. At the upper end of temperature projections, the detrimental impacts of climate change could be very large in ways that cannot be fully comprehended at present.Less
This chapter examines the importance of climate change and its underlying physical processes, and the impact of various degrees of warming on human civilization. The seminars at environment and climate change institutes and departments invite in the campaigners, blurring the boundaries between impartial academic research and partial and committed interests. The climate has always been changing, and within human history there have been substantial swings in global and regional temperatures. Longer growing seasons and milder winters mean that the constraints on economic activities in the cold places (and the costs) are somewhat alleviated. At the upper end of temperature projections, the detrimental impacts of climate change could be very large in ways that cannot be fully comprehended at present.
Thomas S. Bianchi
- Published in print:
- 2006
- Published Online:
- November 2020
- ISBN:
- 9780195160826
- eISBN:
- 9780197562048
- Item type:
- chapter
- Publisher:
- Oxford University Press
- DOI:
- 10.1093/oso/9780195160826.003.0014
- Subject:
- Earth Sciences and Geography, Geochemistry
The uplift of rocks above sea level on the Earth’s surface over geological time, produces rock material that can be altered into soils and sediments by weathering processes. Over geological time, a ...
More
The uplift of rocks above sea level on the Earth’s surface over geological time, produces rock material that can be altered into soils and sediments by weathering processes. Over geological time, a fraction of sediments can be sequestered for storage in the ocean basins—with most of it stored in the coastal margin. However, much of this material is modified via processing in large river estuarine systems which can ultimately affect the long-term fate of these terrigenous materials. Sediments produced from weathering of igneous, metamorphic, and sedimentary rocks are principally transported to the oceans through river systems of the world. The major routes of sediment transport from land to the open ocean can simply be illustrated through the following sequence: streams, rivers, estuaries, shallow coastal waters, canyons, and the abyssal ocean. It should be noted that significant and long-term storage occurs in river valleys and floodplains (Meade, 1996). Submarine canyons are also thought to be temporary storage sites for land-derived sediments; however, episodic events such as turbidity currents and mud slides can move these sediments from canyons to the abyssal ocean (more details on coastal margin transport to the deep ocean are provided in chapter 16). The annual sediment flux from rivers to the global ocean is estimated to range from 18 to 24 × 109 metric tonnes (Milliman and Syvitski, 1992). Conversely, estuaries will eventually fill-in with fluvial inputs of sediments over time, and ultimately reach an equilibrium whereby export and import of sediment supply are balanced (Meade, 1969). For example, recent studies have shown that sediment accumulation in the Hudson River estuary, both short (Olsen et al., 1978) and long term (Peteet and Wong, 2000), is in equilibrium with sea level rise. More specifically, it is believed that river flow controls the direction of sediment flux in the Hudson, while variations in spring-neap tidal amplitude control the magnitude (Geyer et al., 2001). Weathering is typically separated into two categories: physical and chemical. Physical weathering involves the fragmentation of parent rock materials and minerals through processes such as freezing, thawing, heating, cooling, and bioturbation (e.g., endolithic algae, fungi, plant roots, and earthworms).
Less
The uplift of rocks above sea level on the Earth’s surface over geological time, produces rock material that can be altered into soils and sediments by weathering processes. Over geological time, a fraction of sediments can be sequestered for storage in the ocean basins—with most of it stored in the coastal margin. However, much of this material is modified via processing in large river estuarine systems which can ultimately affect the long-term fate of these terrigenous materials. Sediments produced from weathering of igneous, metamorphic, and sedimentary rocks are principally transported to the oceans through river systems of the world. The major routes of sediment transport from land to the open ocean can simply be illustrated through the following sequence: streams, rivers, estuaries, shallow coastal waters, canyons, and the abyssal ocean. It should be noted that significant and long-term storage occurs in river valleys and floodplains (Meade, 1996). Submarine canyons are also thought to be temporary storage sites for land-derived sediments; however, episodic events such as turbidity currents and mud slides can move these sediments from canyons to the abyssal ocean (more details on coastal margin transport to the deep ocean are provided in chapter 16). The annual sediment flux from rivers to the global ocean is estimated to range from 18 to 24 × 109 metric tonnes (Milliman and Syvitski, 1992). Conversely, estuaries will eventually fill-in with fluvial inputs of sediments over time, and ultimately reach an equilibrium whereby export and import of sediment supply are balanced (Meade, 1969). For example, recent studies have shown that sediment accumulation in the Hudson River estuary, both short (Olsen et al., 1978) and long term (Peteet and Wong, 2000), is in equilibrium with sea level rise. More specifically, it is believed that river flow controls the direction of sediment flux in the Hudson, while variations in spring-neap tidal amplitude control the magnitude (Geyer et al., 2001). Weathering is typically separated into two categories: physical and chemical. Physical weathering involves the fragmentation of parent rock materials and minerals through processes such as freezing, thawing, heating, cooling, and bioturbation (e.g., endolithic algae, fungi, plant roots, and earthworms).
Will J. Percival
- Published in print:
- 2015
- Published Online:
- March 2015
- ISBN:
- 9780198728856
- eISBN:
- 9780191795794
- Item type:
- chapter
- Publisher:
- Oxford University Press
- DOI:
- 10.1093/acprof:oso/9780198728856.003.0007
- Subject:
- Physics, Particle Physics / Astrophysics / Cosmology
This chapter describes some of the physical processes underpinning measurements obtained from recent galaxy surveys using multi-object spectrographs on ground-based telescopes. These surveys include ...
More
This chapter describes some of the physical processes underpinning measurements obtained from recent galaxy surveys using multi-object spectrographs on ground-based telescopes. These surveys include the 2-degree Field Galaxy Redshift Survey (2dFGRS), the Sloan Digital Sky Survey (SDSS), and, most recently, the Baryon Oscillation Spectroscopic Survey (BOSS), which is part of the SDSS-III project and has provided the largest volume of the low-redshift universe ever surveyed with a galaxy density useful for high-precision cosmology. The chapter also looks ahead to the next 15 years and the advent of surveys such as the enhanced Baryon Oscillation Spectroscopic Survey (eBOSS), the Dark Energy Spectroscopic Instrument (DESI), and the ESA Euclid satellite mission.Less
This chapter describes some of the physical processes underpinning measurements obtained from recent galaxy surveys using multi-object spectrographs on ground-based telescopes. These surveys include the 2-degree Field Galaxy Redshift Survey (2dFGRS), the Sloan Digital Sky Survey (SDSS), and, most recently, the Baryon Oscillation Spectroscopic Survey (BOSS), which is part of the SDSS-III project and has provided the largest volume of the low-redshift universe ever surveyed with a galaxy density useful for high-precision cosmology. The chapter also looks ahead to the next 15 years and the advent of surveys such as the enhanced Baryon Oscillation Spectroscopic Survey (eBOSS), the Dark Energy Spectroscopic Instrument (DESI), and the ESA Euclid satellite mission.
Nathalie Deruelle and Jean-Philippe Uzan
- Published in print:
- 2018
- Published Online:
- October 2018
- ISBN:
- 9780198786399
- eISBN:
- 9780191828669
- Item type:
- chapter
- Publisher:
- Oxford University Press
- DOI:
- 10.1093/oso/9780198786399.003.0059
- Subject:
- Physics, Particle Physics / Astrophysics / Cosmology
This chapter introduces the Lambda-CDM (cold dark matter) model. In 1948, under the impetus of George Gamow, Robert Hermann, Ralph Alpher, and Hans Bethe in particular, relativistic cosmology entered ...
More
This chapter introduces the Lambda-CDM (cold dark matter) model. In 1948, under the impetus of George Gamow, Robert Hermann, Ralph Alpher, and Hans Bethe in particular, relativistic cosmology entered the second phase of its history. In this phase, physical processes, in particular, nuclear and atomic processes, are taken into account. This provides two observational tests of the model: primordial nucleosynthesis, which explains the origin of light nuclei, and the existence of the cosmic microwave background, and it establishes the fact that the universe has a thermal history. Study of the large-scale structure of the universe then indicates the existence of dark matter and a nonzero cosmological constant. This model, known as the ΛCDM model, is the standard model of contemporary cosmology.Less
This chapter introduces the Lambda-CDM (cold dark matter) model. In 1948, under the impetus of George Gamow, Robert Hermann, Ralph Alpher, and Hans Bethe in particular, relativistic cosmology entered the second phase of its history. In this phase, physical processes, in particular, nuclear and atomic processes, are taken into account. This provides two observational tests of the model: primordial nucleosynthesis, which explains the origin of light nuclei, and the existence of the cosmic microwave background, and it establishes the fact that the universe has a thermal history. Study of the large-scale structure of the universe then indicates the existence of dark matter and a nonzero cosmological constant. This model, known as the ΛCDM model, is the standard model of contemporary cosmology.