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You agree that we have no liability for any damages. What is geography? To make this study more manageable, geography is divided into two main branches of study namely: Human geography Physical geography However, geography can be divided into many sub-branches representing the various factors of the earth and the environment.
Physical geography Physical geography deals with the physical characteristics of the earth such as; bodies of water, climate, soils, natural vegetation and animal life. Regional geography Regional geography looks at different regions of the earth and by using various factors, determines the similarities or differences of the regions.
What is geology? That is, where people live is thought to be of minor importance. Geographic research, however, has established the importance of "the fluid, constantly reworked local political cultures of particular places" Agnew, , p. Similarly, geographic work has highlighted the importance of place in the formation of cultural and social identities and experiences.
In this late-twentieth-century world, as Americans struggle to address the tensions and celebrate the richness of human differences—of ethnicity, race, nationality, gender, and generation—a focus on the ways that ideas about place serve to divide people but also to connect them can offer new visions for personal and social values Agnew, Geographers have also challenged the tendency of much social science research to treat the environment in which people live merely as a passive byproduct of history.
They have argued that the material characteristics of the environments in which people live reflect and influence personal, social, and environmental understandings. As the social sciences begin to take more seriously the role of symbols and images in human affairs, geography's concern with the social dimensions of landscapes has taken on new relevance and visibility.
By focusing on the tangible environments where people live and work, geographic research is part of a growing thrust within the social sciences to understand the importance of everyday life in social change e. At the same time, geographers are affecting the direction of that thrust by linking human ideas and actions to the settings in which they are embedded.
Geographic research addressing integration in place has put the discipline at the frontier of experimentation with integration as a challenge for science. Geography's experience with integration in place also has been fruitful in providing insights to issues of interest to science at large, as illustrated by the following examples of complexity and nonlinearity and central tendency and variation. Geographic research on integration in place is also important to scientific understanding of important societal issues.
Three examples are given below—on economic health, ecosystem change, and conflict and cooperation —to illustrate this importance. Places are natural laboratories for the study of complexity because places exhibit a wide array of interlocking processes and activities, as well as interconnections with other places. Nonlinear growth and decline also are found locally in part because introduced processes or activities may not encounter well-developed moderating influences.
Geographers have examined the complex and nonlinear systems of places to better understand how and why places change. This research shows that early settlement patterns can create "path dependencies" for the future evolution of settlement systems. It also shows how economic restructuring, such as the shift from mercantilism to industrial capitalism, can create "bifurcation" of settlement systems with new nodes of growth in some regions and dissipation of growth in others Borchert, , ; Conzen, ; Dunn, ; Pred, Theoretical research has identified how the complexity of spatial economic dynamics reflects disequilibrating contradictions and social conflicts, resulting in periodic attempts by the private sector and the state to overcome emerging conflicts and crises through spatial restructuring Harvey, ; Sheppard and Barnes, Geographers have applied systems theory to help understand the complex interactions between nature and society that are caused by natural hazards, including multiple adjustments and attendant feedbacks Cutter, Geographers have also examined the mechanisms of ecosystem stability and change, especially human and other agents of short-and long-term ecosystem change Zimmerer, Ideas about chaotic behavior or catastrophic events within places, additionally, have contributed to research on growth within and among cities Allen and Sanglier, ; Dendrinos, These studies illustrate geographers' contributions to a more fundamental understanding of environmental and social systems in ways that should engage ecologists, engineers, mathematicians, physicists, and other members of the scientific community.
Other geographic research has been directed toward the identification and description of patterns that may have emerged from nonlinear, complex, or chaotic dynamics. Fractal dimensions, in particular, have been used to simplify and represent the outcomes of nonlinear, chaotic, or complex dynamics Goodchild and Mark, Urban settings Batty and Longley, as well as satellite and map images Malanson et al.
Interactions in space and with nature tend to result in certain spatial and environmental regularities, leading to the study of expected outcomes, or central tendencies, across geography's domains of interest Chorley and Haggett, Geographers have recognized, however, that observable geometries in the social and physical worlds are dynamic in their nature and multidimensional in their explanation.
Certain geographic patterns reflect efficiency as in economic production systems , but only under rather narrowly defined conditions that are subject to change such as the time or cost of travel and to inherent variability.
Together, change and inherent variability often influence the observed variation, which can take the form of unsystematic departures from central tendency, changes to the central tendency itself, or alterations in the variance structure. Changes in variation can signal shifts from one system state to another; therefore, variation cannot be.
Geographic research into the nature of change and variability, as well as into central tendency, has revealed much about the dynamics of places Dendrinos, As in other sciences, geographers also have recognized that variation and central tendency are usually interdependent and cannot be evaluated or understood separately.
A geographic perspective recognizes that economic changes can create or exacerbate economic imbalances across places, whether or not the economic system overall is trending toward or away from equilibrium. A particular concern of geographers is the implications of economic change for different groups in society within a place, especially for groups distinguished by class, gender, and race.
Related issues include the composition of the work force as rooted in social forces and potentials for cooperation versus conflict see Sidebar 5.
Geographers have examined high-technology centers to evaluate their potential as models for regional growth in other areas see Sidebar 5.
They have noted that locational considerations are different for innovation centers than for other industrial activities such as branch plants e. Since labor is less mobile than capital, regional growth related to technological change is likely to follow existing patterns of labor skills, which increases the challenges for areas that do not now have competitive skill levels Malecki, Scientific concerns about environmental change have increased markedly in the past few decades.
Geographers have made important contributions to the understanding of such changes through their research on human-induced climate change, ecosystem dynamics and biodiversity, and earth surface processes. For example, human populations are increasingly concentrated in urban and suburban regions.
Land surfaces in these areas, in turn, are being transformed into highly unnatural mosaics, mosaics often dominated by interconnected and impervious patches of buildings and transportation networks. With the transformation of rural landscapes into suburban and urban landscapes comes dramatic changes in local and regional climates see Sidebar 5.
Urban heating and drying, for example, have been measured and simulated by geographers for decades e. Geographers' research not only has brought to light climatic consequences of urbanization, but their models have begun to provide a means for assessing the potential climatic impacts of future urbanization. Another focus of environmental change research involves reconstructing recent disturbance patterns and ecosystem processes in forest, shrubland, and desert communities through careful fieldwork and historical analyses see Sidebar 5.
Urbanization dramatically alters the land surface and converts preurban local or regional climates into distinctively "urban climates. Using integrated programs of fieldwork and numerical modeling, geographers have been at the forefront of assessing urban influences especially the effects of urban surface materials and morphology on local and regional climates Oke, Research by geographers also is beginning to suggest that extensive land surface changes associated with urban-and suburbanization occurring worldwide may be contributing to global climate change.
Sue Grimmond and Tim Oke have been particularly effective at integrating in-the-field measurement programs with the numerical modeling of urban climates Grimmond and Oke, ; Grimmond et al. Making and evaluating heat and moisture flux observations, as well as compiling surface character databases, their research teams have examined a number of North American cities, including Los Angeles, Chicago, Miami, Vancouver, Sacramento, Tucson, and Mexico City.
Not only have they documented the considerable variability that exists both within and between cities, but their analyses show that daily patterns of the fluxes and the timing of the peaks are remarkably similar among the cities. Their measurements further indicate that evapotranspiration is even higher than expected in many residential areas, owing to the irrigation of planted vegetation.
Evapotranspiration in other parts of the city tends to be quite low, as available energy mostly warms the urban fabric.
Grimmond and colleagues have also been able to use geographic information systems GISs to help synthesize land surface information, field measurements, and model simulations Grimmond and Souch, Their innovative approaches are revealing the often elusive source regions of the heat and moisture fluxes e. Although others have investigated source regions, Grimmond and colleagues are identifying and quantifying them more precisely than ever before and in turn are clarifying the spatial and temporal relationships between urbanization and attendant climate change.
Their results have the potential to help isolate the influences of built environments on global climate change. Geographers also are addressing ecosystem disturbance and change over longer time scales through analysis of lake sediments from a variety of ecosystems Horn, ; Liu and Fearn, ; Whitlock, The pooling of paleoenvironmental datasets over large regions has allowed geographers to map species ranges and ecosystem boundaries for selected times during the past 2 million years Wright et al.
These maps document the biotic response to past global changes and also provide a means of evaluating models of the Earth's climate system. One of the most pressing issues for global and regional environmental change is ecosystem change, including the loss of biodiversity USGCRP, For example, geographers study the distributions of plant and animal species and how these distributions are shaped by local and regional environmental conditions—including human activity—and by human-influenced migration and selection Sauer, Geography also has a long tradition of studying the spatial patterning and.
This tradition predates recent concerns about biodiversity loss. An important focus of recent geographic work has been spatial variations in the nature, recurrence, and biotic consequences of human and natural disturbances such as fires, treefalls, forest clearance, and floods Vale, This research provides essential knowledge for devising systems to preserve biodiversity at local, regional, and global scales Baker, a; Young, ; Medley, ; Savage, In their focus on Earth surface processes, geographers are paying increased attention to the nature of change itself, and the transitions between different change states.
There also is increasing interest in the flows of energy and mass through and across the Earth surface system as an avenue to understanding the underlying structure of environmental change. Geographic investigations explore such changes on time scales ranging from less than a single year to hundreds of thousands of years.
At time scales of decades to centuries, geographic work is concerned mainly with documenting changes in Earth surface systems and assessing underlying causes. One focus of geographic research, for example, involves the reconstruction of historical dimensions of glaciers through photographs and surveys in order to assess regional climate change e. Another important focus of geographic work at these time scales concerns the effects of human settlement on river systems—for example, the work of Kesel et al.
Wolman and his students on the effects of urbanization on water and sediment runoff to rivers; work beginning with Grove Karl Gilbert on the impacts of mining on river systems see also James, ; Mossa and Autin, ; work by T. Dunne and other geographers e. At time scales of 10, to , years, another concern of geographic research has been understanding connections between climatic changes and the Earth's physical response, such as the effects of orbital changes on the amount of effective solar radiation received at the Earth's surface Cervany, These so-called Orbital or Milankovitch changes have been used to explain periodic "floods" of icebergs in the northern Atlantic and other ocean surface responses Broecker, , and terrestrial changes in climate as recorded by rock varnish Liu and Dorn, Evidence for terrestrial climate change has been documented from such diverse sources as wind-deposited silts loess on the Great Plains Feng et al.
In any effort to understand how individuals and groups relate to one another, context is fundamental. Geography's concerns with the integration of phenomena in place and the positioning of one place with respect to others are key to an understanding of context; they focus attention on the importance of such matters as resources, land use, and the distribution and movements of peoples.
Geographic work highlights the connections between social forces and the material and spatial circumstances in which they are embedded. For example, geographers have shown how conflicts over water have affected everything from territorial disputes in the Middle East Kliot, to gender relations in West Africa Carney, ; Schroeder, Research into the so-called urban underclass has shown how the geographic concentration of minority populations is contributing to their alienation as a result of discrimination and suburban exclusion in the housing market, suburbanization of well-paid jobs, inadequate financing of education in central cities, and the out-migration of better-off ethnic minorities who have gained access to suburban housing markets e.
Studies along these lines contribute to larger efforts to understand the nature of social and ethnic conflicts. They point to the necessity of moving beyond sociological analysis to understand how the material and spatial attributes of specific places affect the formation and interaction of social and ethnic groups.
Such studies provide insights into connections and relationships that matter in the ongoing interdisciplinary effort to better understand the forces shaping conflict and cooperation. In many ways, geography is a science of flows. It sees the world not as a static mosaic of spatial units but as an ever-changing tapestry of landscapes, movements, and interactions. As noted in Chapter 3 , geographers recognize that "place" is defined in part by the movement of peoples, goods, and ideas from other locations.
Studies of interdependencies between places are well represented in geography's literatures. For example, for more than a generation, geography has been a leader in improving quantitative models that help to explain, predict, and optimize spatial interactions.
Contemporary work in this field seeks to incorporate behavioral dimensions of spatial interaction and to capitalize on advances in spatial econometrics. Although there has been heated debate over the meaning. Contributions by geographers to our understanding of the interdependencies between places are illustrated by studies of spatial economic flows, human migration, and watershed dynamics, as illustrated in the following subsections.
Following the basic work of Wilson and others, geographers have researched the movement of people, commodities, and capital and the spatial choice patterns of consumers in relation to alternative service sites.
This research addresses spatial interactions of individuals at the microlevel and interregional flows at the macrolevel. At the microlevel, geographers have observed that patterns of spatial interaction differ by socioeconomic class and gender Hanson, , affected by such characteristics as income, family responsibilities and geographic relationships within an extended family, and the experience and expectations of the individual and of those with whom the individual interacts.
To the extent that these effects can be modeled and generalized, they help geographers understand the operation of local labor markets, shopping patterns, and information diffusion. An interdisciplinary body of research by geographers, economists, and sociologists has indeed shown that one of the most persistent empirical correlates of commodity and population flows is distance, even in situations where standard economic and sociological variables perform inconsistently.
Geographers argue, however, that distance itself is not a datum but a social construction whose influence changes with shifts in the barriers between, and communication technologies linking, different places. Data on interactions among places e.
The problem is compounded by the multiple geographic scales at which interactions occur. For example, case-study, survey-based data suggest that trade between states in the United States has probably been increasing over the past two decades, yet more is known about each state's international trade than about its trade with other parts of the country.
Figure 5. Although spatial patterns of sales and purchases vary significantly from state to state, there is a symmetry of states' sales to and purchases from interstate regions, despite the different nature of goods imported and exported from a given state. Correlation coefficients for state firms' sales and purchases by region are on the order of 0.
Modeling of spatial interaction data is at the heart of geographic analysis. The expansion method of generating models that embed temporal or spatial shifts. This method has gained widespread use in geographic analysis, from its introduction into the literature Casetti, to its use in a range of applications and interpretations Jones and Casetti, Research by geographers and regional scientists has shown how to derive spatial interaction models based on either traditional information theory or optimal decision making theory.
This theoretical work has been extended to analysis of the interaction between consumers and suppliers of services. Spatial interaction simulations can pose "what if" questions about retail patterns and behavior similar to the questions about the flows of goods among states. Much of the literature in relatively new academic journals such as Geographical Systems; Location Science; and Computers, Environments, and Urban Systems contains illustrations of such models.
Decisions to relocate are among the more important decisions made by households, with far-reaching implications for the links between places. Conceptualization of the search and selection process by Wolpert and Brown and Moore has been formalized in a model of decision making and housing search under uncertainty Smith et al.
In addition to the advances in the Middle East , the Chinese empire in Asia also contributed immensely to geography. Until about , China was the most prosperous civilization on Earth.
The Chinese were scientifically advanced, especially in the field of astronomy. Around , they also achieved one of the most important developments in the history of geography: They were the first to use the compass for navigation al purposes.
Curiosity was awakened; a desire to trade with wealthy Asian cultures motivated a renewed interest in exploring the world. The period of time between the 15th and 17th centuries is known in the West as the Age of Exploration or the Age of Discovery. With the dawn of the Age of Discovery, the study of geography regained popularity in Europe.
The invention of the printing press in the mids helped spread geographic knowledge by making maps and chart s widely available. Improvements in shipbuilding and navigation facilitate d more exploring, greatly improving the accuracy of maps and geographic information. Greater geographic understanding allowed European powers to extend their global influence.
During the Age of Discovery, European nations established colonies around the world. Improved transportation , communication , and navigational technology allowed countries such as the United Kingdom to successfully govern colonies as far away as the Americas, Asia, Australia, and Africa. Geography was not just a subject that made colonialism possible, however.
It also helped people understand the planet on which they lived. Not surprisingly, geography became an important focus of study in schools and universities. Geography also became an important part of other academic discipline s, such as chemistry , economics , and philosophy. In fact, every academic subject has some geographic connection. Chemists study where certain chemical element s, such as gold or silver , can be found. Economists examine which nations trade with other nations, and what resource s are exchanged.
Philosophers analyze the responsibility people have to take care of the Earth. Emergence of Modern Geography Some people have trouble understanding the complete scope of the discipline of geography because, unlike most other disciplines, geography is not defined by one particular topic. Instead, geography is concerned with many different topics—people, culture, politics , settlements, plants, landform s, and much more. What distinguishes geography is that it approaches the study of diverse topics in a particular way that is, from a particular perspective.
It looks at these different distributions and arrangements at many different scales. Geography seeks to understand where things are found and why they are present in those places; how things that are located in the same or distant places influence one another over time; and why places and the people who live in them develop and change in particular ways.
But exploration no longer simply means going to places that have not been visited before. It means document ing and trying to explain the variations that exist across the surface of Earth, as well as figuring out what those variations mean for the future.
The age-old practice of mapping still plays an important role in this type of exploration, but exploration can also be done by using images from satellite s or gathering information from interviews.
Discoveries can come by using computers to map and analyze the relationship among things in geographic space, or from piecing together the multiple forces, near and far, that shape the way individual places develop. Studies of the geographic distribution of human settlements have shown how economic forces and modes of transport influence the location of towns and cities. For example, geographic analysis has pointed to the role of the U. Interstate Highway System and the rapid growth of car ownership in creating a boom in U.
The geographic perspective helped show where Americans were moving, why they were moving there, and how their new living places affected their lives, their relationships with others, and their interactions with the environment.
Geographic analyses of the spread of disease s have pointed to the conditions that allow particular diseases to develop and spread. When cholera broke out in London, England, in , Snow represented the deaths per household on a street map. Using the map, he was able to trace the source of the outbreak to a water pump on the corner of Broad Street and Cambridge Street.
The geographic perspective helped identify the source of the problem the water from a specific pump and allowed people to avoid the disease avoiding water from that pump. Investigations of the geographic impact of human activities have advanced understanding of the role of humans in transforming the surface of Earth, exposing the spatial extent of threats such as water pollution by manmade waste. For example, geographic study has shown that a large mass of tiny pieces of plastic currently floating in the Pacific Ocean is approximately the size of Texas.
Because the study of geography is so broad, the discipline is typically divided into specialties. At the broadest level, geography is divided into physical geography , human geography , geographic techniques , and regional geography. Physical Geography The natural environment is the primary concern of physical geographers, although many physical geographers also look at how humans have altered natural systems.
Some disciplines within physical geography include geomorphology , glaciology , pedology , hydrology , climatology , biogeography , and oceanography. Geomorphology is the study of landforms and the processes that shape them. Geomorphologists investigate the nature and impact of wind , ice, rivers, erosion , earthquake s, volcano es, living things, and other forces that shape and change the surface of the Earth. Glaciologists document the properties and distribution of glaciers and iceberg s.
Data collected by glaciologists has demonstrated the retreat of Arctic and Antarctic ice in the past century.
Pedologists study soil and how it is created, changed, and classified. Soil studies are used by a variety of professions, from farmer s analyzing field fertility to engineer s investigating the suitability of different areas for building heavy structures. Hydrologists study the water cycle through rainfall into streams, lake s, the soil, and underground aquifer s. Hydrologists provide insight s that are critical to building or removing dam s, designing irrigation systems, monitoring water quality , tracking drought conditions, and predicting flood risk.
For example, climatologists make predictions about El Nino , a cyclical weather phenomenon of warm surface temperature s in the Pacific Ocean. They analyze the dramatic worldwide climate changes caused by El Nino, such as flooding in Peru, drought in Australia, and, in the United States, the oddities of heavy Texas rains or an unseasonably warm Minnesota winter.
Biogeographers study the impact of the environment on the distribution of plants and animals. Geology is important, as developing the resources of a countryits explorations are requisite to make out where the coal, iron and mineral veins are concealedto discover the locnlity of building stones, and marbles, and of clays for bricks, and also to determine their extent, and the best places to commence their working. Now, let us inquire the means at command for attaining these objects.
The governments of nearly every country having any pretensions to civilization have now an org'anized body of scientific men to make these geographical and geological charts, sections and maps. IVe have a Coast Survey, and we are occasionally sending out exploring expeditions whose aim is to do the work we have mentioned.
Each State has its geologist and scientific corps for exploring and giving to the world an account of its rcsources and capabilities. Great Britain has her Ordnance Survey, and her ships of war are always carrying on this work of mapping the globe.
Germany has her great band of scientific amateurs, and the learned of each nation are voluntarily doing their utmost for the good of the world. A vast amount of labor has been done in this field by the means we have specified, but there yet remains much to be done, and we would point this out as a sphere of enterprise in which many can engage, and by first makin" a chart of their own district they may exte:d theirlabors to wider and unexplored fields.
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