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The Association for Geographical Studies

CONCEPT OF NATURAL IN PHYSICAL

Dr. Ritu Ahlawat

Associate Professor of Geography, Miranda House, University of Delhi, Delhi -110007. Email: [email protected], [email protected]

Received: 5 February 2013; Revised: 19 April, 2013; Accepted: 22 April, 2013 Uploaded: 22 April, 2013

Introduction operations of Earth as we all Location, region, human-earth depend on Earth‟s systems to provide relationships, place and movement are five oxygen, water, nutrients, energy, and fundamental themes of geography. Within materials to support . The growing these five themes, geography is governed by complexity and pressure on the human- a method rather than by a specific body of Earth relation requires that we shift our knowledge, and this method is called spatial study of geographic processes towards the analysis. centers on more holistic or complete, perspective – spatial analysis of all the physical elements such is the thrust of Earth system science. and processes that make up the Hence, a general understanding of the environment: air, water, , , system concept is essential. In this paper, landforms, soils, animals, plants and Earth attempt has been made to give a itself. It investigates the spatial patterns and comprehensive understanding of the aspects processes of Earth‟s natural systems and as stated in learning objectives. their human interactions. Process, a set of actions or mechanisms that operate in some Learning Objectives: special order, is central to geographic - Origin of the Concept of System analysis. Numerous processes are involved - Definition and Characteristics of in Earth‟s vast water--weather System system or in continental crust movements - Earth System and earthquake occurrences. - Earth System Functions, Processes Geographers use spatial analysis to and Structure examine how Earth‟s processes interact over - Components of Natural Systems of space or area. As a science, physical Earth geographic studies use the scientific method which is very important in modern Earth Origin of Concept of System sciences, in which the goal is to understand Whether considering the first a whole functioning Earth, rather than systems of written communication with isolated, small compartments. Such Phoenician cuneiform to Mayan numerals, understanding allows the scientists to or the feats of engineering with the Egyptian construct models that simulate general pyramids, systems thinking in essence dates

AGS Study Material Series, Paper- VII, 2013 Ahlawat, 2013 The Association for Geographical Studies back to antiquity. While modern systems are historically influenced all areas from the considerably more complicated, today‟s social to hard sciences, the original theorists systems are embedded in history. Now, the explored the implications of twentieth word system pervades our daily: century advances in terms of systems. “Check the car‟ cooling system”; “How Subjects like complexity, self-organization, does the grading system work?”; “There is a connectionism and adaptive systems had weather system approaching”. Systems of already been studied in the 1940s and many kinds surround us. Not surprisingly, 1950s. In fields like , researchers system analysis has moved to the forefront examined complex systems using as a method for understanding operational mathematics and no more than pencil and behaviour in many disciplines. paper. John von Neumann discovered as an area of study cellular automata and self-reproducing specifically developed following the World systems, again with only pencil and paper. Wars from the work of Ludwig von A few others worked on the foundations of Bertalanffy, , Kenneth E. without any at all. At Boulding, William Ross Ashby, Margaret the same time Howard T. Odum, the Mead, , C. West radiation ecologist recognised that the study Churchman and others in the 1950s. of general systems required a language that Cognizant of advances in science that could depict energetics and kinetics at any questioned classical assumptions in the system scale. Odum developed a general organizational sciences, Bertalanffy's (1950) systems, or Universal language, based on idea to develop a theory of systems began as the circuit language of electronics to fulfill early as the interwar period. Systems theory this role, known as the Energy Systems as a technical and general academic area of Language. System philosophy, methodology study predominantly refers to the science of and application are complementary to this systems in initiating what became a project science. It is an interdisciplinary field of of systems research and practice. In general science. It studies the nature of theory (GST), he writes: "...there systems in nature, society, and science. exist models, principles, and laws that apply More specifically, it is a framework by to generalized systems or their subclasses, which one can analyze and/or describe any irrespective of their particular kind, the group of objects that work in concert to nature of their component elements, and the produce some result. This could be a single relationships or "forces" between them. It organism, any organization or society, or seems legitimate to ask for a theory, not of any electro-mechanical or informational systems of a more or less special kind, but of artifact. In all these studies, systems concept universal principles applying to systems in is often associated with cybernetics, which general”. is the study of and derived Where assumptions in Western concepts such as communication and science from Greek thought with Plato and control in living organisms, machines and Aristotle to Newton‟s Principia have organisations.

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System Definition and Characteristics connected and joined together by a web of The world is a concrete system, relationships. The Primer group defines which we define as a nonrandom system as a family of relationships among accumulation of matter and energy in a the members acting as a whole. Bertalanffy region in physical Space-time organized defined system as “elements in standing into interacting, interrelated subsystems and relationship”. components. The word "system" also refers Simply stated, a system is any to systems of actions abstracted from the ordered interrelated set of things and their behavior of organisms (abstracted svstems) attributes, linked by flows of energy and and to systems of ideas expressed in matter, as distinct from the surrounding symbolic form (conceptual systems); but the environment outside the system. The first meaning will be intended here unless elements within a system may be arranged we specify one of the others. Concrete in a series or interwoven with one another. systems are phenomena of the physical A system comprises any number of world. They include atoms, molecules, subsystems. planets, solar systems, star systems, All systems share the following seven galaxies, and; ultimately, the entire common characteristics: universe. of all sorts are also 1. Systems have a structure that is concrete systems, as are ecological systems defined by its parts and processes. with biotic and abiotic components. The 2. Systems are generalizations of various machines people make and use as reality. well as man-machine and animal-machine 3. Systems tend to function in the same systems are also concrete systems. Below way. All systems consist of groups atoms are electrons, protons, neutrons, and of parts that interact with each other other subatomic particles. The concept of according to various cause and effect level is of major importance. Systems at any processes. given level are more like each other in many 4. The various parts of a system have ways than like systems at other levels. Total functional as well as structural system variables are measurable in the same relationships between each other. way subsystem variables are. Within levels, 5. The fact that functional relationships systems can be compared with norms exist between the parts suggests the established for their particular types to flow and transfer of some type of determine adequacy of adjustment energy or matter. Systems exchange processes. Banathy defines a perspective energy and matter internally and/or that iterates this view: matter beyond their defined “The systems view is a world-view boundary with their surrounding that is based on the discipline of System environment through various Inquiry and central to systems inquiry is the processes of input and output. concept of system. In the most general sense, system means a configuration of parts

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6. Functional relationships can only Earth System functions occur because of the presence of a Within Earth‟s systems both matter driving force. and energy are stored and retrieved, and 7. The parts that make up a system energy is transformed from one type to show some degree of integration - in another. Matter is an entity that assumes a other words the parts work well physical shape and occupies space; energy together. is a capacity to change the motion of, or to do work on, matter. Depending upon flows The Earth System of energy and matter, the systems may be The planet Earth is a mixed living closed or open (Fig. 1). and nonliving system. It is the suprasystem of an supranational systems as well as the total ecological system, with all its living and nonliving components. From the moment of its formation, it has been evolving, with the result that its present state is unlike its state in earlier geologic periods. Scientists are collecting the data that win increase their understanding of the past and Heat present states of Earth as a system. loss Earth System Study is very much an interdisciplinary concept that is mainly based upon the integration of knowledge from the traditional subjects of and Physical Geography. It involves the study of all of the Earth's major systems, which includes everything from the solid Earth to surface and near-surface processes, such as glaciation, oceanic Fig. 1: Flows in Open and Closed System circulation and climate. Earth System (After Christopherson, 1997) Science is more than just a close integration of Geoscience topics. An important part of Closed System the Earth System Science concept is to try to A system that is shut off from the explain past, present and possible future surrounding environment so that it is self- changes on the Earth resulting from contained is a closed system. Although such disturbance of its systems and interactions closed systems are rarely found in nature, between them. Earth system is essentially closed with respect to matter and resources, which are recycled within the Earth system. The only exceptions are the slow escape of lightweight gases (such as hydrogen) from

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Ahlawat, 2013 The Association for Geographical Studies the atmosphere into the space and the input level are generally damped out in long-run. of frequent but tiny meteors and cosmic and Some environmental systems exhibit meteoric dust, although major impacts from medium-term change, for example, wildlife planetoids occur every 100 million years or populations which fluctuate in number so. through periods longer than one season. Further, while dealing with the pattern of Open System systems behavior, we need to allow for lag Systems in nature are generally not time, rhythms or jumps. An example of lag self-contained. Inputs of energy and matter between input and response can be seen in flow into the system and outputs of energy day-time heating of land surface and and matter flow from the system. Earth height. In the same way, it takes time for system is open with respect to energy that rainwater from a heavy storm to become enters and exits from outside. Most Earth concentrated as floodwater in a valley systems are dynamic. storm. The lag time, considerable in human terms, is very short on the geologic time- Structure and Process of System scale. The structure, function, and history of At any time, the parts of a concrete a system interact. Structure changes as the system, living or nonliving, are arranged in system functions from moment to moment. space in a specific pattern. This spatial All these can be better understood through arrangement is the system's structure. As the feedback mechanisms and states of system. parts of the system move in relation to one another, structure changes. System change Feedback Loops can be continuous or episodic, or may As a system operates, it generates remain relatively fixed over long time outputs that influence its own operations. spans. These outputs function as “information” that Process includes both the system's is returned to various points in the system function, the often reversible actions that via pathways called feedback loops. succeed each other from moment to Feedback information can control (or at moment, and its history, the less reversible least guide) further system operations. If the or irreversible changes that alter both the feedback information discourages response structure and the function of the system. of the system, it is called . Aging of organisms, decay of mountain Further production in the system decreases ranges, and cooling of sun are historical the growth of the system. It causes self- processes. The regular beating of a heart is regulation in a natural system, stabilization functional. The scars that result from a and maintaining the system, e.g. a landslide coronary occlusion make a permanent looses energy as friction increases and slope historical change in the heart muscle. All flattens. change in a system over time is process. If feedback information encourages Some processes exhibit cyclic patterns of increased response of the system, it is called behaviour, e.g. seasonal fluctuations in lake , sometimes called the

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„snowball‟ effect. Further production in the condition described as dynamic equilibrium system stimulates the growth of the system, (Fig. 2b). These changing trends of either e.g. fire generates heat that dries air and fuel increasing or decreasing system operations increasing the fire intensity. Unchecked may appear gradual over time, e.g. long- positive feedback in a system can create a term climate changes and the present pattern runway condition. In natural systems, such of increasing temperatures in the unchecked growth will reach a critical limit, atmosphere and , or erosion and loss leading to instability, disruption, or death of of many beaches. The present rate of species organisms. extinction exhibits a downward trend in Feedback loops among subsystems, numbers of living species and change in the and to and from the environment, are found “balance of nature”. Like many of Earth‟s in all living systems. In general, lower-level systems, slopes exist in a state of dynamic systems have a more limited range of equilibrium. Inputs of energy and matter adjustments than higher level systems and, alter the balance of the system causing it to within each level, the more highly evolved periodically adjust, then re-establish and systems have a greater range than those equilibrium. Given the nature of systems to below them in the evolutionary scale. maintain their operations, they tend to resist abrupt change. System Equilibrium Most systems maintain structure and character over time. An energy and material system that remains balanced over time, where conditions are constant or recur, is in steady-state condition. When the rates of inputs and outputs in the systems are equal and the amounts of energy and matter in storage within the system are constant, the system is in steady-state equilibrium (Fig. 2 a). The concept of steady state is similar to the concepts of equilibrium and (A physiological term that applies to a state of balance of the variables of an organism). One example of a steady state that must be maintained by cells and organisms is water balance. These systems must excrete water at about the same rate that they take it in or Fig.2: System Equilibrium they suffer damage. a) Steady State (b) Dynamic However, a steady-state system (After Christopherson, 1997) fluctuating around an average value may demonstrate a changing trend over time, a

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However, a system may reach a threshold at Cascading systems: These systems receive which it can no longer maintain its and make complex inputs and outputs of character, so it lurches to a new operational matter, energy, or both, e.g. cascade of solar level through step function that is a rapid radiation wherein incoming radiation is change or jump from one state to another.. highly complex, extending on two sides of This abrupt change places the system in a visible light into infra-red and ultra-violet metastable equilibrium, e.g. a landscape ranges and radiation from Earth into space such as hillside or coastal bluff that adjusts takes place in another band of wavelength. after a sudden landslide. A new equilibrium However, complex the system may be but is eventually achieved among slope, both inputs and outputs are balanced. materials, and energy over time. The Cascading systems commonly include some threshold concept raises concern in the kind of regulator and they also provide for , especially if some storage. For example, clouds act as thermal natural systems reach such limits. The regulator for maintenance of heat balance of relatively sudden collapse of six ice shelves Earth‟s surface. Other examples of these surrounding a portion of Antarctica serves systems include cascade of precipitation on as an example of systems reaching a the land, the rock waste moving downslope threshold and changing to a new status, that toward river channels, the cascade of water of disintegration. moving through channel systems toward the sea. Whereas the internal geometry System Structures constitutes morphological system but when As the point of interest is limited to the viewpoint is extended to flow of water open Earth systems in a state limited to and sediment, then it becomes cascading condition of equilibrium or disequilibrium, a system. classification scheme is required that is independent both of function and state. It is Process-response control systems: These provided by system structure wherein Earth systems change their internal geometry systems types in increasing order of and/or behaviour in response to cascading complexity have been identified as follows: inputs. The systems involved are linked together in some way, and may have Morphological systems: They are defined components and operations in common. in terms of their internal geometry – the This process-response study is highly number, size, shape and linkages of the important in the understanding of Earth components, e.g. stream network map, systems. It deals with how things work and mineral substances forming crystals, joints also with lag time between input and in rocks, shorelines, entire continents and response, with the connection between landscape systems are identifiable by their process and form, and with tolerance limits, distinct shapes and patterns. i.e. thresholds beyond which an increase in input leads to a breakdown of system behaviour. For example, changes in lake

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Ahlawat, 2013 The Association for Geographical Studies level and area in response to increases and living) systems overlapping to form the decreases in the cascade of precipitation or realm of the biotic (living) system. Each water from surrounding land. Behavior of system loosely occupies a “shell” around lake‟s response will be different in different Earth, so each is called “sphere”. The environments of arid and humid . abiotic spheres are the atmosphere, Control systems are process-response lithosphere and . The biotic systems in which parts of the operation are sphere is called or ecosphere. controlled by intelligence. They vary greatly Because these four systems are not in scale. On a small scale a farm is also a independent units in nature, their boundaries control system wherein soil responds to must be understood as transition zones natural cascades but cropping plan is rather than sharp delimitations. controlled by decisions of farmer. 1. Atmosphere Components of Earth's Natural System The atmosphere is a thin, gaseous Earth‟s surface is a vast area of 500 veil surrounding Earth, held to the planet by million square kilometers and it has been the force of gravity, mixes with elements of described as a "heat engine" in other planetary spheres, and occupies the which matter is continually cycled by spaces or voids in soils, sediments and convection from the hot mantle to the crust rocks. Formed by gases arising from within and atmosphere and back to the mantle. Earth‟s crust and interior, and the Geologic evidence indicates that the heat exhalations of all life over time, the lower that drives these cycles and causes atmosphere is unique in the Solar system. It development of the crust and atmosphere is a combination of nitrogen (78%), oxygen has declined during the lifetime of the earth. (21%), argon (0.9%), carbon dioxide Consequently, cycling of material through (0.04%) water vapour and trace gases. The the system has slowed. Since, like all atmosphere protects life on Earth by physical systems, this one is subject to absorbing ultraviolet solar radiation, entropy, Earth will continue to cool. warming the surface through heat retention Powered by radiant energy from the sun, (greenhouse effect), and reducing water on Earth also moves in cycles from temperature extremes between day and sea and land surfaces to the atmosphere, night. The impacts of the atmosphere on the forms clouds, and falls back to the surface other spheres, and vice-versa, are typically as rain or snow. The atmosphere itself is in manifested in terms of climate. The continual motion as temperature and temperature of the Earth's atmosphere varies pressure gradients and the earth's rotation with altitude of five different atmospheric produce winds and air currents. layers (Fig. 4). The open Earth systems invariably reflect the interactions between four major 2. Hydrosphere spheres of the planetary environment. Fig. 3 The hydrosphere encompasses water shows a simple model of three abiotic (non- in all its forms. Earth‟s waters exist in the

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Ahlawat, 2013 The Association for Geographical Studies atmosphere, on the surface, and in the crust 3. Lithosphere near the surface. Collectively, these three Earth‟s crust and a portion of the areas are the home to the hydrosphere. upper mantle directly below the crust form Water of the hydrosphere exists in its all the lithosphere having a depth of about 100 three states: liquid, solid (the frozen km (Fig. 6). The crust is quite brittle ), and gaseous (water vapour). compared with the layers deep beneath the The flows and cycles of water as well as surface, which move slowly in response to changes in its states comprise the single an uneven distribution of heat and pressure. most important mechanism for interactions The lithosphere refers to the solid, inorganic between the spheres (Fig. 5). Water occurs material of the Earth, principally rock, soil, in two general chemical conditions, saline and sediment. From the Earth surface (97%) and a very little fresh. It exhibits system perspective, the most important important heat-storage properties and is an aspects of lithospheric processes are those extraordinary solvent. Among the planets in manifested at the surface, and the the Solar system, only Earth possesses water predominance of impacts of other spheres is in such quantity, adding to Earth‟s restricted to crust. An important component uniqueness among the planets. of the lithosphere is soil, which generally covers Earth‟s land surfaces; the soil layer sometimes is referred to as the Edaphosphere.

Fig. 3: Earth’s Spheres (After Christopherson, 1997) Fig. 4: Layers of Atmosphere (Source: http://ds9.ssl.berkeley.edu/ lws_gems/3/images_3/layat510.jpg)

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Various energy fluxes operate in the the mantle as new crust is formed from geomorphic system. Volcanic eruptions that upwelling magma. Tectonic strains build up carry magma from the deep interior to the and are reduced in earthquakes. Sea water surface and spew volcanic ash and gases moves in repetitive cycles between the into the atmosphere are part of this cycling ocean bottom and hot basaltic rocks below process. So too are movements of the great the sea floor, transferring dissolved minerals tectonic plates into which the crust is from lower layers to the sea. Matter divided. Their movement in relation to each circulates at rates and in temporal patterns other changes the geography of Earth. characteristic of each of these cycles. Continents change their boundaries and Therefore, the interactions between the relative positions. Plates collide to build lithosphere and other spheres are largely mountains, separate to form new seas, and controlled expressed in terms of landforms slide beneath the sea bottom to be melted in and weathered outer “skin” of the earth.

Fig. 5: Hydrological System (Source: http://www.itc.nl/ research/themes/watercycle/_pict/w atercycle.jpg)

Fig. 6: Earth's Interior Layers (After Christopherson, 1997)

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4. Biosphere/Ecosphere Earth with all its living and nonliving The intricate, interconnected web components. that links all organisms with their physical environment is the biosphere. Sometimes Interactions between spheres called the ecosphere, the biosphere is the These spheres are closely connected. area in which physical and chemical factors For example, many birds (biosphere) fly form the extent of life. The biosphere exists through the air (atmosphere), while water in the overlap among the abiotic spheres, (hydrosphere) often flows through the soil extending from the sea floor to about 8 km (lithosphere). In fact, the spheres are so into the atmosphere. Life is sustainable closely connected that a change in one within the natural limits. In turn, life sphere often results in a change in one or processes have powerfully shaped the other more of the other spheres. Such changes that three spheres through various interactive take place within an are referred processes. The biosphere evolves, re- to as events. organizes itself at times, faces extinctions, Events can occur naturally, such as and manages to flourish. The impacts of the an earthquake or a hurricane, or they can be biosphere on the inorganic spheres can be caused by humans, such as an oil spill or air equally profound, up to and including the pollution. An event can cause changes to exertion of important controls on the very occur in one or more of the spheres, and/or composition of atmosphere, and effects on an event can be the effect of changes in one the lithosphere to the point that in some or more of Earth's four spheres. This two- cases much of the regolith can be referred to way cause and effect relationship between as biomantle. an event and a sphere is called an Earth‟s biosphere is the only one interaction. Interactions also occur among known in the Solar system; thus, life as the spheres; for example, a change in the know it is unique to Earth. This entity, the atmosphere can cause a change in the Earth's biosphere, together with the hydrosphere, and vice versa. atmosphere, , and soil, forms a Interactions that occur as the result complex cybernetic system which seeks an of events such as floods and forest fires optimal physical and chemical environment impact only a local region, meaning the for life. The flow of energy causes cyclic flood waters can only travel so many miles flow of matter as explained by food chain from the original stream, and only the trees example in Fig.7 (See Box). Thus, a forest that lie within the area on fire will be ecosystem includes all living organisms. In burned. On the other hand, the effects of these ecological systems, living systems at events such as El Nino or ozone depletion levels from cells to supranational systems may cause interactions that can be observed interact with each other and with the worldwide. For example, the El Nino event- nonliving environments upon which they -a change in the ocean currents off the coast depend. Local are parts of larger of Peru-- can cause changes in weather systems up to the total ecological system of patterns all the

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A Food Chain as an example of system

A food chain models the movement of energy in an ecosystem (a form of environmental system). Figure 7 below illustrates the movement of energy in a typical food chain. In this diagram, we begin the food chain with 100,000 units of light energy from the Sun. Note, the amount of energy available at each successive level (called trophic levels) of this system becomes progressively less. Only 10 units of energy are available at the last level (carnivores) of the food chain. A number of factors limit the assimilation of energy from one level to the next.

The Sun is the original source of energy, in the form of light, for the food chain. (100,000 Units of Energy)

Plants capture approximately 1% of the available light energy from the Sun for biomass production by way of photosynthesis. Photosynthesis can be described chemically as: Light Energy + 6CO2 + 6H2O ==> C6H12O6 + 6O2 .(1,000 Units of Energy)

Herbivores consume approximately 10% of the plant biomass produced in a typical food chain. (100 Units of Energy)

Carnivores capture and consume about 10% of the energy stored by the herbivores.(10 Units of Energy)

Fig.7: Model of the Grazing Food Chain Showing the Movement of Energy through an Ecosystem. (After Pidwirny, M. (1999)

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Ahlawat, 2013 The Association for Geographical Studies way across North America, while ozone scale dislocation of human settlements and depletion above Antarctica may result in land use. increased levels of ultra-violet B radiation Thus, man has certainly not been an around the world. Understanding the unmixed blessing to the Earth system since, interactions among the earth's spheres and in his relatively brief tenure, he has shown the events that occur within the ecosystem an alarming capability to destroy not only allows people to predict the outcomes of himself but other critical components of the events. Being able to predict outcomes is system as a whole. In fact, a new sphere useful when, for example, developers wish called anthrosphere is now being given wide to know the environmental effects of a attention in the light of changing landscape project such as building an airport before and processes of Earth. At the same time, they begin construction. human systems are characterized by an Understanding the interactions that enormous capacity to process and occur in the earth system also helps people disseminate information. to prepare for the effects of natural disasters Because of the complicated such as volcanic eruptions; this connecting population, natural understanding allows people to predict resources, capital investment, food supplies, things like how far and in what direction the and pollution, change in one may produce lava will flow. unexpected and undesirable consequences in others. In addition, short and long-term Challenges and Human Policy for Earth outcomes of attempts to make adjustments System have made opposite effects, with the result Exceeding carrying capacity of some that success in the short run in controlling a parts of the Earth, depleting natural given variable may, in the long run, lead to resources faster than they can be replaced, its increase beyond its state prior to the extruded wastes of human systems polluting intervention. Earth and loss of wild habitats are The Earth sciences are now in a destroying nonhuman living systems at a period of advance in theory, experiment, rate that could extinguish 15-20% of all observation, and instrumentation that is species on Earth by the year 2000 (Council producing the necessary data. It is only now on Environmental Quality and the that we are beginning to study the major Department of State). Another threat to the chemical flux rates between the major Earth system is apparent in the increasing geospheres. It is these rate processes that amount of carbon dioxide in the ultimately provide the global buffer atmosphere. Among the possible effects of systems. We are also concerned with the even a relatively moderate warming would interface between the atmosphere and the be large regional climatic changes that radiation field of space. The conclusion would alter the location of deserts, fertile drawn from simulations is that unless world areas, and marginal lands and cause large- policy makers choose to suppress growth in the world system, the internal dynamics of

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Ahlawat, 2013 The Association for Geographical Studies the system itself will produce an undesirable Christopherson (1997) Elemental equilibrium. In its concern for similar Geosystems, 3rd Edition. Pearson Prentice problems, the United Nations has sponsored Hall, New Jersey. a global input-output analysis and a set of alternative projections of the demographic, Pidwirny, M. (1999) Introduction to System economic, and environmental states of the Theory at http//:www.PhysicalGeography. world. net There is today no worldwide Phillips, J.D. (1999) Earth Surface Systems: with the power to set policy Complexity, Order and Scale, Blackwell and secure the cooperation of the world's Pub., Oxford. nations in a unified analysis, development of a remedial plan, and implementation of Laszlo, E. (1972) The Systems View of the such a plan. Systems at the level of the World, The Natural Philosophy of the New society are the dominant human political Developments in the Sciences. New York: systems. A great deal of supranational George Brazillier. decision making goes on in the world in supranational and international Miller, J. G. and Miller, J. L. The Earth as A organizations, conferences, and meetings System, Center for the Study of Democratic among national deciders, but nations Institutions, University of California at comply with decisions of these bodies only Santa Barbara. http://www. newciv.org when they perceive that the recommended /ISSS_Primer courses of action are in their own best Odum, H. (1994) Ecological and General interests. It may well be that securing such Systems: An introduction to systems cooperation is the most important task now , Colorado University Press, facing human beings as well as our mother Colorado. Earth. Strahler, A. and Strahler, A. (2005) Physical Geography: Science and Systems of the Bibliography Human Environment, 3rd Edition John Bertalanffy, L. von. (1950) "An Outline of Wiley, New York. General Systems Theory", British Journal Wilson, A. G. (1981) Geography and the for the Philosophy of Science, Vol. 1, No. 2. Environment: Systems Analytical Methods. cited at online article on System Theory John Wiley, New York. (http://en.wikipedia.org/wiki/Systems_theor y) Wheeling Jesuit University/NASA- supported Classroom of the Future (1997) Bloom, A. L. (1998) Geomorphology: A Earth System Science, Online article at Systematic Analysis of Late Cenozoic http://www.cotf.edu/ete/ESS/ESSmain.html Landforms. Prentice Hall, New Jersey.

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