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Geography The word “geography” was adopted in the 3rd century BC by the Greek scholar Eratosthenes and means “Earth description”. Today’s geographers investigate a wide range of world issues—from the erosive power of glaciers in Iceland to the explosive growth of large metropolitan cities and the alarming rate of deforestation in the Amazon. Some geographers research the spread of infectious diseases in certain areas. Others may examine why people in different regions vote in certain patterns or tend to migrate more than others. These scientists and social scientists may spend months or years in foreign countries to understand how regional, social, economic, and other factors influence various groups of people, including indigenous peoples, minorities, women, children, or the poor. Globalization, interdependence among countries, and unequal development are becoming vital issues in today’s world of rapid change. |
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Geographers identify, analyse, and interpret the distribution and arrangement of features on the Earth’s surface. They also study the relationship of humans to their environment, which includes both physical and cultural features. Physical features include climate, land and water, and plant and animal life. Cultural features include entities that people create, such as nations, settlements, lines of communication, modes of transport, office buildings, religious shrines, and other modifications to the physical environment. Geography draws from many other sciences and social sciences, including economics, political science, history, biology, geology, mathematics, and computer science. The work of geographers is important to urban, regional, and environmental planning. Geographic education is sometimes divided into five interdependent areas. These are (1) location—a description of absolute and relative location; (2) place—natural and manufactured aspects of a location that make it unique; (3) human-environment interaction—the positive and negative effects one can have on the other; (4) movement—transport and communication; and (5) regions—the location and description of different areas. History of Geography |
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| Geography is one of the
oldest academic disciplines. Ancient peoples such as the Chinese, the
Egyptians, and the Phoenicians made long journeys and recorded their
observations of foreign lands. By 1400 BC, the shores
of the Mediterranean
Sea had been explored and charted, and during the next thousand
years, early explorers visited Great
Britain and navigated most of the African coast.
The ancient Greeks gave the western world its first formal knowledge of the structure, size, and general nature of the Earth. The Greek geographer and historian Strabo (63? BC–AD 24?) wrote a 17-volume encyclopedia entitled Geography, which served as a valuable source of information for military commanders and public administrators of the Roman Empire. During the 2nd century AD, the Greek astronomer Ptolemy compiled most Greek and Roman geographical knowledge known up to that time. He also proposed new methods of cartography. His maps showed that he understood the problems involved in projecting, or representing, a spherical Earth on a flat surface. During the Middle Ages, Europeans carried out little travel and exploration, and there was practically no advancement in geography. Among Europeans, only the Vikings of Scandinavia were active in exploration. Arabs, however, interpreted and tested the works of the earlier Greek and Roman geographers and explored Africa and the Middle East. As early as the 700s, Arab scholars were translating the works of the Greek geographers into Arabic. The translation of these Arabic texts into Latin helped spread Greek geographical learning through Europe. The most important geographer of the Arab world was al-Idrisi (1100–1165?), known for his detailed maps. Voyages and studies during the 16th century proved beyond a doubt that the Earth is a sphere. Previously, many people, including Christian leaders, believed the Earth to be flat. Branches of Geography |
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| Most geographers today
divide the science of geography into two fundamental branches: systematic
and regional geography. Systematic geography explores the physical and
cultural elements of the Earth. Regional geography looks at various areas
of the Earth, especially the combinations of physical and cultural
features that make each region unique. These two branches of geography are
really only different in their approach; they are interdependent, and most
geographers use a combination of both.
Systematic Geography |
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| Systematic geography
includes physical geography and human geography. These classifications are
made up of specialized fields.
Physical geography, which involves the study of the physical features of the Earth, includes the following branches:
Regional Geography |
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| Regional geography
examines the differences and similarities among the various regions of the
Earth.
This branch of geography seeks explanations for the diversity of
environments through the study of language, agriculture, terrain,
local economic systems, and other factors. Regional geographers may study
the development of a small area such as a city, or they may focus on large
areas, such as the Mediterranean
region or an entire continent.
Methods of Geography |
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| The chief goal of
geographers is to understand the environment and the human use of that
environment. To do this, they collect geographical data; record the
results of geographic studies in the form of charts, graphs, textbooks,
and maps; and analyse the information gathered. Geographers use a variety
of techniques and tools to achieve this goal.
Collecting Data |
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| Geographers collect data
either in the field—from observation, interviews, and measuring—or
from secondary sources—census
information, statistical surveys, maps, and photographs. Advances made
since World War II in aerial photography such as a type of remote sensing
that uses special films and techniques for obtaining multi-dimensional
views of the landscape, help geographers to study details of the Earth and
its resources. Geographers also use radar, underwater craft called
bathyspheres, and equipment that drills into the Earth’s crust
to obtain information about the features of the Earth.
Remote sensing with satellites has had a revolutionary impact on the field of geography. Information obtained from the Landsat satellite is used to map land use, manage forested land, estimate crop production, monitor grazing conditions, assess water quality, and protect wildlife. Since 1986, France’s SPOT satellites have provided images of objects as small as 100 square metres (1,076 square feet) and have produced stereoscopic images useful for topographic mapping. Earth-observing satellites have also been launched by the European Space Agency and by Japan, Russia, India, and other nations. Another revolutionary technology is the Global Positioning System (GPS), a series of satellites that provide precise information on location, altitude, and time. As of March 1994, 24 GPS satellites were in operation. GPS applications continue to grow in land, sea, air, and space navigation. The ability to enhance safety and decrease fuel consumption will make GPS an important component of travel in the international airspace system. Aeroplanes will use GPS for landing at fogbound airports; motor vehicles will use GPS as part of intelligent transport systems. Cartography |
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| One of the most important
subdivisions of geography is cartography,
the art and science of creating, using, and studying maps. Most cultures
have made and used maps at some time. People have drawn lines in the sand
and marked places and paths on animal skins, bone, ivory, bark, and paper
to help others to travel to a particular location.
The map is the most important tool of geography and can record simple data and present the results of a complicated geographical study. By reading map symbols, map users can understand not only the location but also the characteristics of features in a particular area. The earliest existing maps were made by the Babylonians in about 2300 BC. Cut on clay tiles, they were largely land surveys made for the purposes of taxation. |
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More extensive regional maps, drawn on silk and dating from the 2nd century BC, have been found in China. One of the most interesting maps is the stick chart constructed by the Marshall Islanders in the South Pacific Ocean. This chart is made of a gridwork of cane fibres arranged to show the location of islands and the direction of ocean currents, winds, and waves. In AD 1570 Abraham Ortelius, a Flemish cartographer, published the first modern atlas, Orbis Terrarum, which contained 70 maps. During the 16th century many other cartographers produced maps that incorporated the ever-increasing information brought back by navigators and explorers. Gerardus Mercator, however, stands out as the greatest cartographer of the age of discovery; his cylindrical projection of 1568 proved invaluable to all future navigators. Using a Mercator map, a navigator can plot a course simply by drawing a line between two points and reading the compass direction from the map. Although the Mercator projection represents directions faithfully, it greatly distorts sizes of land mass in the high latitudes. During the 20th century, cartography underwent a series of major technical innovations. Aerial photography, satellites, and computers have all revolutionized the creation and distribution of maps. Analyzing Geographical Information |
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| Beginning in the late
1950s, geographers made increasing use of quantitative
methods—techniques that use mathematics or statistics to analyse data.
The change in methodology in the 1950s and 1960s was so rapid that it is
sometimes called the quantitative revolution. Using quantitative methods,
geographers can study a large amount of data together with a large number
of variables and rationalize them.
Frequently, geographers collect data and form a hypothesis to explain their observations. They then test this hypothesis using quantitative methods. Sometimes the resulting theories are expressed as mathematical statements, called models. Geographical theories and models do not necessarily apply to all places at all times, but are developed instead to explain observed tendencies. Quantitative methods have been particularly useful in applications of location theory, a study of the factors that influence the location of geographical entities, such as towns or factories. A developing country, for example, may have resources to build three new hospitals in the forthcoming year. Geographers may analyse the possible locations, the distribution of the population, travel costs to and from each potential site, and other factors. Using location models, geographers could show where the hospitals should be to provide the best service for the country’s population. Many geographers do not use quantitative methods, but instead use qualitative methods, such as observation, interviewing, and description. Increasingly, geographers use a combination of methods and apply them to many new areas of geographical study. Geographic Information Systems |
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| Computers have become a
particularly useful tool in geography. Geographic information systems
(GIS), in particular, have revolutionized the study of geography. During
the 1960s the Canadian government built the first GIS, a computer system
that records, stores, and analyses geographical information. A GIS
processes large amounts of data and helps scientists to conduct research
much more quickly and accurately. A GIS can generate two- or
three-dimensional images of an area, showing such natural features as hills
and rivers
with artificial features such as roads and power lines. Scientists use GIS
images as models, making precise measurements, gathering data, and testing
ideas with the help of the computer.
Instead of dealing with flat paper maps, cartographers, geographers, and other scientists can now use a GIS to produce spectacular three-dimensional visuals for use in such advanced applications as virtual reality. The Importance of Geography |
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| Geography helps people to
understand their environment and their fellow human beings. Students of
geography learn about the physical features of the Earth
and how important it is to conserve natural
resources. Geography also deals with the similarities of and
differences between people in all parts of the world, where they live, and
how they make a living. By learning about the Earth through geography,
people can better understand and protect the world around them.
For more information on Geography, go to: |
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