GEOGRAPHY

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Physical map of Earth with political borders as
of 2016
Geography (from Greek: γεωγραφία, geographia,
literally "earth description") [1] is a field of
science devoted to the study of the lands,
features, inhabitants, and phenomena of the
Earth and planets. [2] The first person to use the
word γεωγραφία was Eratosthenes (276–194
BC). [3] Geography is an all-encompassing
discipline that seeks an understanding of Earth
and its human and natural complexities —not
merely where objects are, but also how they
have changed and come to be.
Geography is often defined in terms of two
branches: human geography and physical
geography . [4][5] Human geography deals with
the study of people and their communities,
cultures, economies, and interactions with the
environment by studying their relations with and
across space and place. [6] Physical geography
deals with the study of processes and patterns
in the natural environment like the atmosphere ,
hydrosphere, biosphere , and geosphere.
The four historical traditions in geographical
research are: spatial analyses of natural and the
human phenomena, area studies of places and
regions, studies of human-land relationships, and
the Earth sciences . [7] Geography has been called
"the world discipline" [8] and "the bridge between
the human and the physical sciences". [9]
Introduction
Geography is a systematic study of the Universe
and its features. Traditionally, geography has
been associated with cartography and place
names. Although many geographers are trained
in toponymy and cartology , this is not their main
preoccupation. Geographers study the space and
the temporal database distribution of
phenomena, processes, and features as well as
the interaction of humans and their
environment. [10] Because space and place affect
a variety of topics, such as economics , health,
climate , plants and animals, geography is highly
interdisciplinary. The interdisciplinary nature of
the geographical approach depends on an
attentiveness to the relationship between
physical and human phenomena and its spatial
patterns. [11]
Geography as a discipline can be split broadly
into two main subsidiary fields: human
geography and physical geography . The former
largely focuses on the built environment and how
humans create, view, manage, and influence
space. The latter examines the natural
environment, and how organisms , climate, soil ,
water , and landforms produce and interact. [14]
The difference between these approaches led to
a third field, environmental geography, which
combines physical and human geography and
concerns the interactions between the
environment and humans. [10]
Branches
Physical geography
Main article: Physical geography
Physical geography (or physiography) focuses on
geography as an Earth science . It aims to
understand the physical problems and the issues
of lithosphere , hydrosphere, atmosphere ,
pedosphere , and global flora and fauna patterns
( biosphere).
Physical geography can be divided into
many broad categories, including:
Biogeography
Climatology & meteorology
Coastal geography
Environmental management
Geodesy
Geomorphology
Glaciology
Hydrology & hydrography
Landscape ecology
Oceanography
Pedology
Palaeogeography
Quaternary science
Human geography
Main article: Human geography
Human geography is a branch of geography that
focuses on the study of patterns and processes
that shape the human society. It encompasses
the human, political, cultural, social, and
economic aspects.
Human geography can be divided into many
broad categories, such as:
Cultural geography
Development geography
Economic geography
Health geography
Historical & Time geog.
Political geog. & Geopolitics
Pop. geog. or Demography
Religion geography
Social geography
Transportation geography
Tourism geography
Urban geography
Various approaches to the study of human
geography have also arisen through time and
include:
Behavioral geography
Feminist geography
Culture theory
Geosophy
Integrated geography
Main article: Integrated geography
Integrated geography is concerned with the
description of the spatial interactions between
humans and the natural world . It requires an
understanding of the traditional aspects of
physical and human geography, as well as the
ways that human societies conceptualize the
environment. Integrated geography has emerged
as a bridge between human and physical
geography, as a result of the increasing
specialisation of the two sub-fields. Furthermore,
as the human relationship with the environment
has changed as a result of globalization and
technological change , a new approach was
needed to understand the changing and dynamic
relationship. Examples of areas of research in
environmental geography include: emergency
management , environmental management ,
sustainability, and political ecology.
Geomatics
Main article: Geomatics
Digital Elevation Model (DEM)
Geomatics is concerned with the application of
computers to the traditional spatial techniques
used in cartography and topography. Geomatics
emerged from the quantitative revolution in
geography in the mid-1950s. Today, geomatics
methods include spatial analysis , geographic
information systems (GIS) , remote sensing , and
global positioning systems (GPS) . Geomatics
has led to a revitalization of some geography
departments, especially in Northern America
where the subject had a declining status during
the 1950s.
Regional geography
Main article: Regional geography
Regional geography is concerned with the
description of the unique characteristics of a
particular region such as its natural or human
elements. The main aim is to understand, or
define the uniqueness, or character of a
particular region that consists of natural as well
as human elements. Attention is paid also to
regionalization , which covers the proper
techniques of space delimitation into regions.
Related fields
Urban planning, regional planning, and spatial
planning: Use the science of geography to
assist in determining how to develop (or not
develop) the land to meet particular criteria,
such as safety, beauty, economic
opportunities, the preservation of the built or
natural heritage, and so on. The planning of
towns, cities, and rural areas may be seen as
applied geography .
Regional science : In the 1950s, the regional
science movement led by Walter Isard arose
to provide a more quantitative and analytical
base to geographical questions, in contrast to
the descriptive tendencies of traditional
geography programs. Regional science
comprises the body of knowledge in which
the spatial dimension plays a fundamental
role, such as regional economics, resource
management , location theory , urban and
regional planning, transport and
communication , human geography, population
distribution, landscape ecology , and
environmental quality.
Interplanetary Sciences : While the discipline
of geography is normally concerned with the
Earth, the term can also be informally used to
describe the study of other worlds, such as
the planets of the Solar System and even
beyond. The study of systems larger than the
Earth itself usually forms part of Astronomy or
Cosmology. The study of other planets is
usually called planetary science. Alternative
terms such as areology (the study of Mars)
have been proposed but are not widely used.
Techniques
As spatial interrelationships are key to this
synoptic science, maps are a key tool. Classical
cartography has been joined by a more modern
approach to geographical analysis, computer-
based geographic information systems (GIS).
In their study, geographers use four interrelated
approaches:
Systematic – Groups geographical knowledge
into categories that can be explored globally.
Regional – Examines systematic relationships
between categories for a specific region or
location on the planet.
Descriptive – Simply specifies the locations
of features and populations.
Analytical – Asks why we find features and
populations in a specific geographic area.
Cartography
James Cook 's 1770 chart of New
Zealand
Main article: Cartography
Cartography studies the representation of the
Earth's surface with abstract symbols (map
making). Although other subdisciplines of
geography rely on maps for presenting their
analyses, the actual making of maps is abstract
enough to be regarded separately. Cartography
has grown from a collection of drafting
techniques into an actual science.
Cartographers must learn cognitive psychology
and ergonomics to understand which symbols
convey information about the Earth most
effectively, and behavioural psychology to induce
the readers of their maps to act on the
information. They must learn geodesy and fairly
advanced mathematics to understand how the
shape of the Earth affects the distortion of map
symbols projected onto a flat surface for
viewing. It can be said, without much
controversy, that cartography is the seed from
which the larger field of geography grew. Most
geographers will cite a childhood fascination
with maps as an early sign they would end up in
the field.
Geographic information systems
Main article: Geographic information system
Geographic information systems (GIS) deal with
the storage of information about the Earth for
automatic retrieval by a computer, in an accurate
manner appropriate to the information's purpose.
In addition to all of the other subdisciplines of
geography, GIS specialists must understand
computer science and database systems. GIS
has revolutionized the field of cartography: nearly
all mapmaking is now done with the assistance
of some form of GIS software. GIS also refers to
the science of using GIS software and GIS
techniques to represent, analyse, and predict the
spatial relationships. In this context, GIS stands
for geographic information science .
Remote sensing
Main article: Remote sensing
Remote sensing is the science of obtaining
information about Earth features from
measurements made at a distance. Remotely
sensed data comes in many forms, such as
satellite imagery , aerial photography , and data
obtained from hand-held sensors. Geographers
increasingly use remotely sensed data to obtain
information about the Earth's land surface , ocean,
and atmosphere, because it: (a) supplies
objective information at a variety of spatial
scales (local to global), (b) provides a synoptic
view of the area of interest, (c) allows access to
distant and inaccessible sites, (d) provides
spectral information outside the visible portion
of the electromagnetic spectrum, and (e)
facilitates studies of how features/areas change
over time. Remotely sensed data may be
analysed either independently of, or in
conjunction with other digital data layers (e.g., in
a geographic information system).
Quantitative methods
Main article: Geostatistics
Geostatistics deal with quantitative data analysis,
specifically the application of statistical
methodology to the exploration of geographic
phenomena. Geostatistics is used extensively in
a variety of fields, including hydrology, geology,
petroleum exploration, weather analysis, urban
planning, logistics , and epidemiology. The
mathematical basis for geostatistics derives
from cluster analysis , linear discriminant analysis
and non-parametric statistical tests , and a
variety of other subjects. Applications of
geostatistics rely heavily on geographic
information systems, particularly for the
interpolation (estimate) of unmeasured points.
Geographers are making notable contributions to
the method of quantitative techniques.
Qualitative methods
Main article: Ethnography
Geographic qualitative methods, or
ethnographical research techniques, are used by
human geographers. In cultural geography there
is a tradition of employing qualitative research
techniques, also used in anthropology and
sociology. Participant observation and in-depth
interviews provide human geographers with
qualitative data.
History
Main article: History of geography
The oldest known world maps date back to
ancient Babylon from the 9th century BC. [15]
The best known Babylonian world map, however,
is the Imago Mundi of 600 BC. [16] The map as
reconstructed by Eckhard Unger shows Babylon
on the Euphrates, surrounded by a circular
landmass showing Assyria , Urartu [17] and
several cities, in turn surrounded by a "bitter
river" (Oceanus ), with seven islands arranged
around it so as to form a seven-pointed star.
The accompanying text mentions seven outer
regions beyond the encircling ocean. The
descriptions of five of them have survived. [18] In
contrast to the Imago Mundi, an earlier
Babylonian world map dating back to the 9th
century BC depicted Babylon as being further
north from the center of the world, though it is
not certain what that center was supposed to
represent. [15]
The ideas of Anaximander (c. 610–545 BC):
considered by later Greek writers to be the true
founder of geography, come to us through
fragments quoted by his successors.
Anaximander is credited with the invention of the
gnomon , the simple, yet efficient Greek
instrument that allowed the early measurement
of latitude . Thales is also credited with the
prediction of eclipses. The foundations of
geography can be traced to the ancient cultures,
such as the ancient, medieval, and early modern
Chinese. The Greeks, who were the first to
explore geography as both art and science ,
achieved this through Cartography, Philosophy ,
and Literature , or through Mathematics . There is
some debate about who was the first person to
assert that the Earth is spherical in shape, with
the credit going either to Parmenides or
Pythagoras . Anaxagoras was able to
demonstrate that the profile of the Earth was
circular by explaining eclipses . However, he still
believed that the Earth was a flat disk, as did
many of his contemporaries. One of the first
estimates of the radius of the Earth was made
by Eratosthenes . [19]
The first rigorous system of latitude and
longitude lines is credited to Hipparchus . He
employed a sexagesimal system that was
derived from Babylonian mathematics . The
meridians were sub-divided into 360°, with each
degree further subdivided into 60 (minutes ). To
measure the longitude at different locations on
Earth, he suggested using eclipses to determine
the relative difference in time. [20] The extensive
mapping by the Romans as they explored new
lands would later provide a high level of
information for Ptolemy to construct detailed
atlases . He extended the work of Hipparchus ,
using a grid system on his maps and adopting a
length of 56.5 miles for a degree. [21]
From the 3rd century onwards, Chinese methods
of geographical study and writing of
geographical literature became much more
comprehensive than what was found in Europe at
the time (until the 13th century). [22] Chinese
geographers such as Liu An , Pei Xiu, Jia Dan,
Shen Kuo , Fan Chengda , Zhou Daguan , and Xu
Xiake wrote important treatises, yet by the 17th
century advanced ideas and methods of
Western-style geography were adopted in China.
The Ptolemy world map, reconstituted
from Ptolemy 's Geographia , written
c. 150
During the Middle Ages, the fall of the Roman
empire led to a shift in the evolution of
geography from Europe to the Islamic world . [22]
Muslim geographers such as Muhammad al-
Idrisi produced detailed world maps (such as
Tabula Rogeriana ), while other geographers such
as Yaqut al-Hamawi , Abu Rayhan Biruni, Ibn
Battuta , and Ibn Khaldun provided detailed
accounts of their journeys and the geography of
the regions they visited. Turkish geographer,
Mahmud al-Kashgari drew a world map on a
linguistic basis, and later so did Piri Reis ( Piri
Reis map). Further, Islamic scholars translated
and interpreted the earlier works of the Romans
and the Greeks and established the House of
Wisdom in Baghdad for this purpose. [23] Abū
Zayd al-Balkhī , originally from Balkh , founded the
"Balkhī school" of terrestrial mapping in
Baghdad. [24] Suhrāb, a late tenth century
Muslim geographer accompanied a book of
geographical coordinates, with instructions for
making a rectangular world map with
equirectangular projection or cylindrical
equidistant projection. [24] [ verification needed ]
Abu Rayhan Biruni (976–1048) first described a
polar equi- azimuthal equidistant projection of the
celestial sphere. [25] He was regarded as the
most skilled when it came to mapping cities and
measuring the distances between them, which he
did for many cities in the Middle East and the
Indian subcontinent . He often combined
astronomical readings and mathematical
equations, in order to develop methods of pin-
pointing locations by recording degrees of
latitude and longitude . He also developed similar
techniques when it came to measuring the
heights of mountains , depths of the valleys , and
expanse of the horizon. He also discussed
human geography and the planetary habitability
of the Earth. He also calculated the latitude of
Kath, Khwarezm, using the maximum altitude of
the Sun, and solved a complex geodesic
equation in order to accurately compute the
Earth's circumference, which was close to
modern values of the Earth's circumference. [26]
His estimate of 6,339.9 km for the Earth radius
was only 16.8 km less than the modern value of
6,356.7 km. In contrast to his predecessors,
who measured the Earth's circumference by
sighting the Sun simultaneously from two
different locations, al-Biruni developed a new
method of using trigonometric calculations,
based on the angle between a plain and
mountain top, which yielded more accurate
measurements of the Earth's circumference, and
made it possible for it to be measured by a
single person from a single location. [27]
Self portrait of Alexander von Humboldt ,
one of the early pioneers of geography
as an academic subject in modern
sense
The European Age of Discovery during the 16th
and the 17th centuries, where many new lands
were discovered and accounts by European
explorers such as Christopher Columbus, Marco
Polo , and James Cook revived a desire for both
accurate geographic detail, and more solid
theoretical foundations in Europe. The problem
facing both explorers and geographers was
finding the latitude and longitude of a
geographic location. The problem of latitude
was solved long ago but that of longitude
remained; agreeing on what zero meridian should
be was only part of the problem. It was left to
John Harrison to solve it by inventing the
chronometer H-4 in 1760, and later in 1884 for
the International Meridian Conference to adopt by
convention the Greenwich meridian as zero
meridian. [28]
The 18th and the 19th centuries were the times
when geography became recognized as a
discrete academic discipline , and became part
of a typical university curriculum in Europe
(especially Paris and Berlin). The development of
many geographic societies also occurred during
the 19th century, with the foundations of the
Société de Géographie in 1821, [29] the Royal
Geographical Society in 1830, [30] Russian
Geographical Society in 1845, [31] American
Geographical Society in 1851, [32] and the
National Geographic Society in 1888. [33] The
influence of Immanuel Kant, Alexander von
Humboldt , Carl Ritter , and Paul Vidal de la
Blache can be seen as a major turning point in
geography from a philosophy to an academic
subject.
Over the past two centuries, the advancements
in technology with computers have led to the
development of geomatics and new practices
such as participant observation and geostatistics
being incorporated into geography's portfolio of
tools. In the West during the 20th century, the
discipline of geography went through four major
phases: environmental determinism, regional
geography , the quantitative revolution, and
critical geography . The strong interdisciplinary
links between geography and the sciences of
geology and botany, as well as economics,
sociology and demographics have also grown
greatly, especially as a result of earth system
science that seeks to understand the world in a
holistic view.
Notable geographers
Main articles: List of geographers and List of
Graeco-Roman geographers
Gerardus Mercator
Eratosthenes (276–194 BC) – calculated the
size of the Earth.
Strabo (64/63 BC – c. AD 24) – wrote
Geographica, one of the first books outlining
the study of geography.
Ptolemy (c. 90–168) – compiled Greek and
Roman knowledge into the book Geographia.
Al Idrisi (Arabic: ﺃﺑﻮ ﻋﺒﺪ ﺍﻟﻠﻪ ﻣﺤﻤﺪ ﺍﻹﺩﺭﻳﺴﻲ ;
Latin: Dreses) (1100–1165/66) – author of
Nuzhatul Mushtaq.
Gerardus Mercator (1512–1594) – innovative
cartographer produced the mercator projection
Alexander von Humboldt (1769–1859) –
considered father of modern geography,
published Cosmos and founder of the sub-
field biogeography.
Carl Ritter (1779–1859) – considered father
of modern geography, occupied the first chair
of geography at Berlin University.
Arnold Henry Guyot (1807–1884) – noted the
structure of glaciers and advanced
understanding in glacier motion, especially in
fast ice flow.
Radhanath Sikdar (1813–1870) – calculated
the height of Mount Everest .
William Morris Davis (1850–1934) – father of
American geography and developer of the
cycle of erosion .
Paul Vidal de la Blache (1845–1918) –
founder of the French school of geopolitics,
wrote the principles of human geography.
John Francon Williams (1854–1911) - noted
author of The Geography of the Oceans and
other geography works.
Sir Halford Mackinder (1861–1947) – co-
founder of the LSE, Geographical Association .
Ellen Churchill Semple (1863–1932) – first
influential female geographer in the United
States.
Carl O. Sauer (1889–1975) – prominent
cultural geographer.
Walter Christaller (1893–1969) – human
geographer and inventor of Central place
theory .
Yi-Fu Tuan (born 1930) – Chinese-American
scholar credited with starting Humanistic
Geography as a discipline.
Karl W. Butzer (1934–2016) – influential
German-American geographer, cultural
ecologist and environmental archaeologist.
David Harvey (born 1935) – Marxist
geographer and author of theories on spatial
and urban geography, winner of the Vautrin
Lud Prize .
Edward Soja (1941–2015) – noted for his
work on regional development, planning and
governance along with coining the terms
Synekism and Postmetropolis; winner of the
Vautrin Lud Prize .
Michael Frank Goodchild (born 1944) –
prominent GIS scholar and winner of the RGS
founder's medal in 2003.
Doreen Massey (1944–2016) – key scholar in
the space and places of globalization and its
pluralities; winner of the Vautrin Lud Prize .
Nigel Thrift (born 1949) – originator of non-
representational theory .
Institutions and societies
American Geographical Society (US)
Anton Melik Geographical Institute (Slovenia)
American Association of Geographers (AAG)
Institute of Geographical Information Systems
(Pakistan)
Karachi Geographical Society (Pakistan)
National Geographic Society (US)
Royal Canadian Geographical Society
(Canada)
Royal Geographical Society (UK)
Russian Geographical Society (Russia)
Royal Danish Geographical Society (Denmark)
Publications
African Geographical Review
Geographical Review
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