Geography (from

Greek Greek may refer to: Greece Anything of, from, or related to Greece, a country in Southern Europe: *Greeks, an ethnic group. *Greek language, a branch of the Indo-European language family. **Proto-Greek language, the assumed last common ancestor ...

: , ''geographia''. Combination of Greek words ‘Geo’ (The Earth) and ‘Graphien’ (to describe), literally "earth description") is a field of

science Science is a systematic endeavor that Scientific method, builds and organizes knowledge in the form of Testability, testable explanations and predictions about the universe. Science may be as old as the human species, and some of the earli ...

devoted to the study of the lands, features, inhabitants, and phenomena of

Earth Earth is the third planet from the Sun and the only astronomical object known to harbor life. While large volumes of water can be found throughout the Solar System, only Earth sustains liquid surface water. About 71% of Earth's surfa ...

. The first recorded use of the word γεωγραφία was as a title of a book by Greek scholar Eratosthenes (276–194 BC). 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. While geography is specific to Earth, many concepts can be applied more broadly to other celestial bodies in the field of planetary science. One such concept, the

first law of geography The First Law of Geography, according to Waldo Tobler Waldo Rudolph Tobler (November 16, 1930 – February 20, 2018) was an American-Swiss geographer and cartographer. Tobler's idea that "Everything is related to everything else, but near things ...

, proposed by

Waldo Tobler Waldo Rudolph Tobler (November 16, 1930 – February 20, 2018) was an American-Swiss geographer and cartographer. Tobler's idea that "Everything is related to everything else, but near things are more related than distant things" is referred to ...

, is "everything is related to everything else, but near things are more related than distant things." Geography has been called "the world discipline" and "the bridge between the human and the

physical sciences Physical science is a branch of natural science that studies non-living systems, in contrast to life science. It in turn has many branches, each referred to as a "physical science", together called the "physical sciences". Definition Phy ...

Introduction

Geography is a systematic study of the Earth, its features, and phenomena that take place on it. For something to fall into the domain of geography, it generally needs some sort of spatial component that can be placed on a

map A map is a symbolic depiction emphasizing relationships between elements of some space, such as objects, regions, or themes. Many maps are static, fixed to paper or some other durable medium, while others are dynamic or interactive. Although ...

, such as coordinates, place names, or addresses. This has led to geography being associated with

cartography Cartography (; from grc, χάρτης , "papyrus, sheet of paper, map"; and , "write") is the study and practice of making and using maps. Combining science, aesthetics and technique, cartography builds on the premise that reality (or an i ...

and place names. Although many geographers are trained in

toponymy Toponymy, toponymics, or toponomastics is the study of ''toponyms'' ( proper names of places, also known as place names and geographic names), including their origins, meanings, usage and types. Toponym is the general term for a proper name of ...

and cartology, this is not their main preoccupation.

Geographers A geographer is a physical scientist, social scientist or humanist whose area of study is geography, the study of Earth's natural environment and human society, including how society and nature interacts. The Greek prefix "geo" means "earth" a ...

study the Earth's spatial and temporal distribution of phenomena, processes, and features as well as the

interaction Interaction is action that occurs between two or more objects, with broad use in philosophy and the sciences. It may refer to: Science * Interaction hypothesis, a theory of second language acquisition * Interaction (statistics) * Interactions o ...

of humans and their environment. Because space and place affect a variety of topics, such as economics, health,

climate Climate is the long-term weather pattern in an area, typically averaged over 30 years. More rigorously, it is the mean and variability of meteorological variables over a time spanning from months to millions of years. Some of the meteorologi ...

, 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 their spatial patterns. Geography is specific to the planet Earth, and other celestial bodies are specified, such as "geography of Mars," or given another name, such as

areography Areography, also known as the geography of Mars, is a subfield of planetary science that entails the delineation and characterization of regions on Mars. Areography is mainly focused on what is called physical geography on Earth; that is the dis ...

in the case of Mars. Geography as a discipline can be split broadly into three main branches:

human geography Human geography or anthropogeography is the branch of geography that studies spatial relationships between human communities, cultures, economies, and their interactions with the environment. It analyzes spatial interdependencies between social i ...

physical geography Physical geography (also known as physiography) is one of the three main branches of geography. Physical geography is the branch of natural science which deals with the processes and patterns in the natural environment such as the atmosphere, ...

, and

technical geography Technical geography is one of three main branches of geography and involves using, studying, and creating tools to obtain, analyze, interpret, and understand spatial information. The other two branches, human geography and physical geography, can ...

Human geography Human geography or anthropogeography is the branch of geography that studies spatial relationships between human communities, cultures, economies, and their interactions with the environment. It analyzes spatial interdependencies between social i ...

largely focuses on the

built environment The term built environment refers to human-made conditions and is often used in architecture, landscape architecture, urban planning, public health, sociology, and anthropology, among others. These curated spaces provide the setting for human a ...

and how humans create, view, manage, and influence space.

Physical geography Physical geography (also known as physiography) is one of the three main branches of geography. Physical geography is the branch of natural science which deals with the processes and patterns in the natural environment such as the atmosphere, ...

examines the natural environment, and how

organism In biology, an organism () is any living system that functions as an individual entity. All organisms are composed of cells (cell theory). Organisms are classified by taxonomy into groups such as multicellular animals, plants, and ...

s, climate,

soil Soil, also commonly referred to as earth or dirt Dirt is an unclean matter, especially when in contact with a person's clothes, skin, or possessions. In such cases, they are said to become dirty. Common types of dirt include: * Debri ...

, water, and landforms produce and interact. The difference between these approaches led to the development of

integrated geography Integrated geography (also referred to as integrative geography, environmental geography or human–environment geography) is where the branches of human geography and physical geography overlap to describes and explain the spatial aspects of int ...

, which combines physical and human geography and concerns the interactions between the environment and humans.

Technical geography Technical geography is one of three main branches of geography and involves using, studying, and creating tools to obtain, analyze, interpret, and understand spatial information. The other two branches, human geography and physical geography, can ...

involves studying and developing the tools and techniques used by geographers, such as

remote sensing Remote sensing is the acquisition of information about an object or phenomenon without making physical contact with the object, in contrast to in situ or on-site observation. The term is applied especially to acquiring information about Eart ...

, cartography, and geographic information system.

Core concepts

Space

For something to exist in the realm of geography, it must be able to be described spatially. Thus, space is the most fundamental concept at the foundation of geography. The concept is so basic, that geographers often have difficulty defining exactly what it is, and instead assume that everyone knows what they are talking about. At its most fundamental,

absolute space Absolute may refer to: Companies * Absolute Entertainment, a video game publisher * Absolute Radio, (formerly Virgin Radio), independent national radio station in the UK * Absolute Software Corporation, specializes in security and data risk manage ...

is the exact site, or spatial coordinates, of objects, persons, places, or phenomena under investigation. We exist in space. Absolute space leads to the view of the world as a photograph, with everything frozen in place when the coordinates were recorded. Today, geographers are trained to remember that the world is not the static image that appears on a map; and instead, the dynamic space where all processes interact and take place.

Place

Place is one of the most complex terms in geography. In human geography, place is the synthesis of the coordinates on the Earth's surface, the activity and use that occurs, has occurred, and will occur at the coordinates, and the meaning ascribed to the space by human individuals and groups. This can be extraordinarily complex, as different spaces may have different uses at different times and mean different things to different people. In physical geography, a place includes all of the physical phenomena that occur in space, including the lithosphere, atmosphere, hydrosphere, and biosphere. Places do not exist in a vacuum and instead have complex spatial relationships with each other, and place is concerned how a location is situated in relation to all other locations. As a discipline then, the term place in geography includes all spatial phenomena occurring at a location, the diverse uses and meanings humans ascribe to that location, and how that location impacts and is impacted by all other locations on Earth.

Time

Time is usually thought to be within the domain of history, however, it is of significant concern in the discipline of geography. In physics, space and time are not separated, and are combined into the concept of

spacetime In physics, spacetime is a mathematical model that combines the three dimensions of space and one dimension of time into a single four-dimensional manifold. Spacetime diagrams can be used to visualize relativistic effects, such as why differ ...

. Geography is subject to the laws of physics, and in studying things that occur in space, time must be considered. Time in geography is more than just the historical record of events that occurred at various discrete coordinates; but also includes modeling the dynamic movement of people, organisms, and things through space. Time facilitates movement through space, ultimately allowing things to flow through a system. The amount of time an individual, or group of people, spends in a place will often shape their attachment and perspective to that place. Time constrains the possible paths that can be taken through space, given a starting point, possible routes, and rate of travel. Visualizing time over space is challenging in terms of cartography, and includes Space-Prism, advanced 3D geovisualizations, and animated maps.

Scale

Scale in the context of a map is the ratio between a distance measured on the map and the corresponding distance as measured on the ground. This concept is fundamental to the discipline of geography, not just cartography, in that phenomena being investigated appear different depending on the scale used. Scale is the frame that geographers use to measure space, and ultimately to try and understand a place.

Laws of geography

In general, some dispute the entire concept of laws in geography and the social sciences. These criticisms have been addressed by Tobler and others. However, this is an ongoing source of debate in geography and is unlikely to be resolved anytime soon. Several laws have been proposed, and Tobler's first law of geography is the most generally accepted in geography. Some have argued that geographic laws do not need to be numbered. The existence of a first invites a second, and many have proposed themselves as that. It has also been proposed that Tobler's first law of geography should be moved to the second and replaced with another. A few of the proposed laws of geography are below: *

Tobler's first law of geography The First Law of Geography, according to Waldo Tobler, is "everything is related to everything else, but near things are more related than distant things." This first law is the foundation of the fundamental concepts of spatial dependence and spati ...

: "Everything is related to everything else, but near things are more related than distant" *

Tobler's second law of geography The second law of geography, according to Waldo Tobler, is "the phenomenon external to a geographic area of interest affects what goes on inside." Background Tobler's second law of geography, "the phenomenon external to a geographic area of inte ...

: "The phenomenon external to a geographic area of interest affects what goes on inside." *

Arbia's law of geography Arbia’s law of geography states, "Everything is related to everything else, but things observed at a coarse spatial resolution are more related than things observed at a finer resolution." Originally proposed as the 2nd law of geography, this is ...

: "Everything is related to everything else, but things observed at a coarse spatial resolution are more related than things observed at a finer resolution." * The uncertainty principle: "That the geographic world is infinitely complex and that any representation must therefore contain elements of uncertainty, that many definitions used in acquiring geographic data contain elements of vagueness, and that it is impossible to measure location on the Earth's surface exactly."

Sub-disciplines

Geography is a branch of inquiry that focuses on spatial information on Earth. It is an extremely broad topic and can be broken down multiple ways. There have been several approaches to doing this, including "four traditions of geography" and into distinct branches. The Four traditions of geography are often used to divide the different historical approaches geographers have taken to the discipline. In contrast, the branches of geography are used to describe contemporary geographers' approaches.

Four traditions of geography

Geography is an extremely broad field. Because of this, many view the various definitions of geography proposed over the decades as inadequate. To address this, William D. Pattison proposed the concept of the "Four traditions of Geography" in 1964. These traditions are the Spatial or Locational Tradition, the Man-Land or Human-Environment Interaction Tradition, the Area Studies or Regional Tradition, and the Earth Science Tradition. These concepts are broad sets of geography philosophies bound together within the discipline. They are one of many ways geographers organize the major sets of thoughts and philosophies within the discipline.

Spatial or locational tradition

The spatial or locational tradition is concerned with employing quantitative methods to describe the spatial characteristics of a location. The spatial tradition seeks to use the spatial characteristics of a location or phenomena to understand and explain it. The contributors to this tradition were historically cartographers, but it now encompasses what we call technical geography and geographic information science.

Area studies or regional tradition

The area studies or regional tradition is concerned with the description of the unique characteristics of the earth's surface, resulting in each area from the combination of its complete natural or elements, as of physical and human environment. 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 Regionalisation is the tendency to form decentralised regions. Regionalisation or land classification can be observed in various disciplines: *In agriculture, see Agricultural Land Classification. *In biogeography, see Biogeography#Biogeographi ...

, which covers the proper techniques of space

delimitation Boundary delimitation (or simply delimitation) is the drawing of boundaries, particularly of electoral precincts, states, counties or other municipalities.

into regions.

Human-Environment interaction tradition

The Human Environment Interaction tradition (originally the Man-Land), also known as

Integrated geography Integrated geography (also referred to as integrative geography, environmental geography or human–environment geography) is where the branches of human geography and physical geography overlap to describes and explain the spatial aspects of int ...

, is concerned with the description of the spatial interactions between humans and the

natural world ''Natural World'' is a strand of British wildlife documentary programmes broadcast on BBC Two and BBC Two HD and regarded by the BBC as its flagship natural history series. It is the longest-running documentary in its genre on British televis ...

. It requires an understanding of the traditional aspects of physical and human geography, like how human societies conceptualize the environment. Integrated geography has emerged as a bridge between human and physical geography due to the increasing specialization of the two sub-fields. Since the changing of the human relationship with the environment as a result of

globalization Globalization, or globalisation (English in the Commonwealth of Nations, Commonwealth English; American and British English spelling differences#-ise, -ize (-isation, -ization), see spelling differences), is the process of foreign relation ...

and

technological change Technological change (TC) or technological development is the overall process of invention, innovation and diffusion of technology or processes.From ''The New Palgrave Dictionary otechnical change by S. Metcalfe. •biased and biased techno ...

, 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.

Earth science tradition

The Earth science tradition is largely concerned with what is generally referred to as physical geography. The tradition focuses on understanding the spatial characteristics of natural phenomena. Some argue the Earth science tradition is a subset of the spatial tradition, however the two are different enough in their focus and objectives to warrant separation.

Branches of geography

Research and careers in geography today are highly multidisciplinary. Geography is often organized into three branches:

, and

. Geographers rarely focus on just one of these topics, often using one as their primary focus and then incorporating data and methods from the other branches. Geographers are more likely to identify closely with a specific branch when describing themselves to lay people than with grand traditions. Human geography is concerned with studying people and their communities, cultures, economies, and interactions with the environment by studying their relations with and across space and place. Physical geography is concerned with the study of processes and patterns in the natural environment like the atmosphere,

hydrosphere The hydrosphere () is the combined mass of water found on, under, and above the surface of a planet, minor planet, or natural satellite. Although Earth's hydrosphere has been around for about 4 billion years, it continues to change in shape. This ...

biosphere The biosphere (from Greek βίος ''bíos'' "life" and σφαῖρα ''sphaira'' "sphere"), also known as the ecosphere (from Greek οἶκος ''oîkos'' "environment" and σφαῖρα), is the worldwide sum of all ecosystems. It can also ...

, and

geosphere There are several conflicting usages of geosphere, variously defined. It may be taken as the collective name for the lithosphere, the hydrosphere, the cryosphere, and the atmosphere. The different collectives of the geosphere are able to exchange ...

. Technical geography is interested in studying and applying techniques and methods to store, process, analyze, visualize, and use spatial data. These branches use similar geographic philosophies, concepts, and tools and often overlap significantly.

Physical

Physical geography (or physiography) focuses on geography as an Earth science. It aims to understand the physical problems and the issues of lithosphere,

, atmosphere,

pedosphere The pedosphere (from Greek ''pedon'' "ground" or "earth" and ''sphaira'' "sphere") is the outermost layer of the Earth that is composed of soil and subject to soil formation processes. It exists at the interface of the lithosphere, atmosphere, h ...

, and global

flora Flora is all the plant life present in a particular region or time, generally the naturally occurring (indigenous (ecology), indigenous) native plant, native plants. Sometimes bacteria and fungi are also referred to as flora, as in the terms '' ...

and

fauna Fauna is all of the animal life present in a particular region or time. The corresponding term for plants is ''flora'', and for fungi, it is ''funga''. Flora, fauna, funga and other forms of life are collectively referred to as ''Biota (ecology ...

patterns (

). Physical geography is the study of earth's seasons,

, atmosphere,

, streams, landforms, and oceans. Physical geographers will often work in identifying and monitoring the use of natural resources. File:Línea de Wallace.jpg, Biogeography File:Cyclone Catarina from the ISS on March 26 2004.JPG,

Climatology Climatology (from Greek , ''klima'', "place, zone"; and , ''-logia'') or climate science is the scientific study of Earth's climate, typically defined as weather conditions averaged over a period of at least 30 years. This modern field of study ...

and

meteorology Meteorology is a branch of the atmospheric sciences (which include atmospheric chemistry and physics) with a major focus on weather forecasting. The study of meteorology dates back millennia, though significant progress in meteorology did no ...

File:90 mile beach.jpg, Coastal geography File:Gavin Plant.JPG, Environmental management File:Delicate Arch LaSalle.jpg, Geomorphology File:Receding glacier-en.svg,

Glaciology Glaciology (; ) is the scientific study of glaciers, or more generally ice and natural phenomena that involve ice. Glaciology is an interdisciplinary Earth science that integrates geophysics, geology, physical geography, geomorphology, c ...

File:Meander.svg,

Hydrology Hydrology () is the scientific study of the movement, distribution, and management of water on Earth and other planets, including the water cycle, water resources, and environmental watershed sustainability. A practitioner of hydrology is call ...

and

hydrography Hydrography is the branch of applied sciences which deals with the measurement and description of the physical features of oceans, seas, coastal areas, lakes and rivers, as well as with the prediction of their change over time, for the primar ...

File:Khajuraho-landscape.jpg,

Landscape ecology Landscape ecology is the science of studying and improving relationships between ecological processes in the environment and particular ecosystems. This is done within a variety of landscape scales, development spatial patterns, and organizatio ...

File:World11.jpg, Oceanography File:Pangea interpretacion.png, alt=a view of the supercontinent of pangea breaking up,

Palaeogeography Palaeogeography (or paleogeography) is the study of historical geography, generally physical landscapes. Palaeogeography can also include the study of human or cultural environments. When the focus is specifically on landforms, the term pal ...

File:Soil profile.jpg,

Pedology Pedology (from Greek: πέδον, ''pedon'', "soil"; and λόγος, ''logos'', "study") is a discipline within soil science which focuses on understanding and characterizing soil formation, evolution, and the theoretical frameworks for modeling ...

File:Milankovitch Variations sv.png,

Quaternary science Quaternary science is the study which represents the systematic study of the Quaternary Period commonly known as the ice age. The Quaternary Period is a time period that started around 2.58 million years ago and continues today. This perio ...

Human

Human geography (or anthropogeography) is a branch of geography that focuses on studying patterns and processes that shape human society. It encompasses the human, political, cultural, social, and economic aspects. In industry, human geographers often work in city planning, public health, or business analysis. File:Spatial Contextual Awareness Fig 2.png,

Cognitive geography Cognitive geography is an interdisciplinary study of cognitive science and geography. It aims to understand how humans view space, place, and environment. It involves formalizing factors that influence our spatial cognition to create a more eff ...

File:Qichwa conchucos 01.jpg,

Cultural geography Cultural geography is a subfield within human geography. Though the first traces of the study of different nations and cultures on Earth can be dated back to ancient geographers such as Ptolemy or Strabo, cultural geography as academic study first ...

File:Pepsi in India.jpg,

Development geography Development geography is a branch of geography which refers to the standard of living and its quality of life of its human inhabitants. In this context, development is a process of change that affects peoples' lives. It may involve an improvement ...

File:Christaller model 1.jpg,

Economic geography Economic geography is the subfield of human geography which studies economic activity and factors affecting them. It can also be considered a subfield or method in economics. There are four branches of economic geography. There is, primary secto ...

File:Star of life.svg,

Health geography Health geography is the application of geographical information, perspectives, and methods to the study of health, disease, and health care. Medical geography, a sub-discipline of or sister field of health geography, Oxford Bibliographies entry of ...

File:British Empire 1897.jpg,

Historical geography Historical geography is the branch of geography that studies the ways in which geographic phenomena have changed over time. It is a synthesizing discipline which shares both topical and methodological similarities with history, anthropology, eco ...

File:UN General Assembly.jpg, Political geography and Geopolitics File:Pyramide Comores.PNG,

Population geography Population geography relates spatial variations in the distribution, composition, migration, and growth of populations to the terrain. Population geography involves demography in a geographical perspective. It focuses on the characteristics of po ...

Demography Demography () is the statistical study of populations, especially human beings. Demographic analysis examines and measures the dimensions and dynamics of populations; it can cover whole societies or groups defined by criteria such as edu ...

File:ReligionSymbol.svg, Religion geography File:US-hoosier-family.jpg, Social geography File:Gare du Nord USFRT (Paris Metro).png,

Transportation geography Transport geography or transportation geography is a branch of geography that investigates the movement and connections between people, goods and information on the Earth's surface. Aims and scope Transportation geography detects, describes, and ...

File:Tourists-2.jpg,

Tourism geography Tourism geography is the study of travel and tourism, as an industry and as a social and cultural activity. Tourism geography covers a wide range of interests including the environmental impact of tourism, the geographies of tourism and leisure ec ...

File:New-York-Jan2005.jpg,

Urban geography Urban geography is the subdiscipline of geography that derives from a study of cities and urban processes. Urban geographers and urbanists examine various aspects of urban life and the built environment. Scholars, activists, and the public have ...

Various approaches to the study of human geography have also arisen through time and include: *

Behavioral geography Behavioral geography is an approach to human geography that examines human behavior by separating it into different parts. In addition, behavioral geography is an ideology/approach in human geography that makes use of the methods and assumptions of ...

Culture theory Culture theory is the branch of comparative anthropology and semiotics (not to be confused with cultural sociology or cultural studies) that seeks to define the heuristic concept of culture in operational and/or scientific terms. Overview In t ...

* Feminist geography * Geosophy

Technical

Technical geography concerns studying and developing tools, techniques, and statistical methods employed to collect, analyze, use, and understand spatial data. Technical geography is the most recently recognized of the branches. As academic fields increasingly specialize in their nature, technical geography has emerged as a branch of geography specializing in geographic methods and thought. The emergence of technical geography has brought new relevance to the broad discipline of geography by serving as a set of unique methods for managing the interdisciplinary nature of the discipline. While human and physical geographers use the techniques employed by technical geographers, technical geography is more concerned with the fundamental spatial concepts and technologies than the nature of the data. A technical geographer might work as a GIS analyst or create general reference maps incorporating human and natural features. File:The Cartographic Process.png,

Cartography Cartography (; from grc, χάρτης , "papyrus, sheet of paper, map"; and , "write") is the study and practice of making and using maps. Combining science, aesthetics and technique, cartography builds on the premise that reality (or an i ...

File:Australian Census 2011 demographic map - Australia by SLA - BCP field 2715 Christianity Anglican Persons.svg,

Digital mapping Digital mapping (also called digital or computer cartography) is the process by which a collection of spatial data is compiled and formatted into a virtual image on a computer. The primary function of this technology is to produce maps that give a ...

File:Worldwind.png,

Geoinformatics Geoinformatics is the science and the technology which develops and uses information science infrastructure to address the problems of geography, cartography, geosciences and related branches of science and engineering, such as Land Surveying. ...

File:Fig 4.4.png, Geographic information science File:Geoservices server with apps.png, Geographic information systems File:Euclidean Voronoi diagram.svg,

Geostatistics Geostatistics is a branch of statistics focusing on spatial or spatiotemporal datasets. Developed originally to predict probability distributions of ore grades for mining operations, it is currently applied in diverse disciplines including p ...

File:Survey instruments-2.png,

Geomatics Geomatics is defined in the ISO/TC 211 series of standards as the " discipline concerned with the collection, distribution, storage, analysis, processing, presentation of geographic data or geographic information". Under another definition, it ...

File:gislayers.jpg,

Geovisualization Geovisualization or geovisualisation (short for geographic visualization), also known as cartographic visualization, refers to a set of tools and techniques supporting the analysis of geospatial data through the use of interactive visualization. Li ...

File:GPS-IIR.jpg,

Global Positioning System The Global Positioning System (GPS), originally Navstar GPS, is a satellite-based radionavigation system owned by the United States government and operated by the United States Space Force. It is one of the global navigation satellite sy ...

File:Meridian convergence and spehrical excess.png,

Geodesy Geodesy ( ) is the Earth science of accurately measuring and understanding Earth's figure (geometric shape and size), orientation in space, and gravity. The field also incorporates studies of how these properties change over time and equivale ...

File:World map of submarine cables.png,

Internet GIS Internet GIS, or Internet geographic information systems, is a term that refers to a broad set of technologies and applications that employ the Internet to access, analyze, visualize, and distribute spatial data. Introduction Internet GIS is an ...

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Map algebra Map algebra is an algebra for manipulating geographic data, primarily Field (geography) , fields. Developed by Dr. Dana Tomlin and others in the late 1970s, it is a set of primitive operations in a geographic information system (GIS) which allows ...

Image:Alpha2000.jpg,

Photogrammetry Photogrammetry is the science and technology of obtaining reliable information about physical objects and the environment through the process of recording, measuring and interpreting photographic images and patterns of electromagnetic radiant ima ...

File:Remote Sensing Illustration.jpg,

Remote Sensing Remote sensing is the acquisition of information about an object or phenomenon without making physical contact with the object, in contrast to in situ or on-site observation. The term is applied especially to acquiring information about Earth ...

File:Example_krig.png,

Spatial analysis Spatial analysis or spatial statistics includes any of the formal techniques which studies entities using their topological, geometric, or geographic properties. Spatial analysis includes a variety of techniques, many still in their early deve ...

File:Sample of time geographical description.png,

Time geography Time geography or time-space geography is an evolving transdisciplinary perspective on spatial and temporal processes and events such as social interaction, ecological interaction, social and environmental change, and biographies of individuals. T ...

File:Smartphone with navigation map app.jpg,

Web mapping Web mapping or an online mapping is the process of using maps, usually created through geographic information systems (GIS), on the Internet, more specifically in the World Wide Web (WWW). A web map or an online map is both served and consumed, t ...

Related fields

Planetary science Planetary science (or more rarely, planetology) is the scientific study of planets (including Earth), celestial bodies (such as moons, asteroids, comets) and planetary systems (in particular those of the Solar System) and the processes of their f ...

: 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

planet A planet is a large, rounded astronomical body that is neither a star nor its remnant. The best available theory of planet formation is the nebular hypothesis, which posits that an interstellar cloud collapses out of a nebula to create a you ...

s of the

Solar System The Solar SystemCapitalization of the name varies. The International Astronomical Union, the authoritative body regarding astronomical nomenclature, specifies capitalizing the names of all individual astronomical objects but uses mixed "Solar S ...

and even beyond. The study of systems larger than the Earth itself usually forms part of

Astronomy Astronomy () is a natural science that studies astronomical object, celestial objects and phenomena. It uses mathematics, physics, and chemistry in order to explain their origin and chronology of the Universe, evolution. Objects of interest ...

Cosmology Cosmology () is a branch of physics and metaphysics dealing with the nature of the universe. The term ''cosmology'' was first used in English in 1656 in Thomas Blount (lexicographer), Thomas Blount's ''Glossographia'', and in 1731 taken up in ...

. The study of other planets is usually called planetary science. Alternative terms such as

areography (geography of Mars) Areography, also known as the geography of Mars, is a subfield of planetary science that entails the delineation and characterization of regions on Mars. Areography is mainly focused on what is called physical geography on Earth; that is the dis ...

have been employed to describe the study of other celestial objects. Ultimately, geography may be considered a subdiscipline within planetary science.

Techniques

All geographic research and analysis start with asking the question "where," followed by "why there." Geographers start with the fundamental assumption set forth in

, that "everything is related to everything else, but near things are more related than distant things." As spatial interrelationships are key to this synoptic science, maps are a key tool. Classical

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: * Analytical – Asks ''why'' we find features and populations in a specific geographic area. * Descriptive – Simply specifies the locations of features and populations. * Regional – Examines systematic relationships between categories for a specific region or location on the planet. * Systematic – Groups geographical knowledge into categories that can be explored globally.

Quantitative methods

Quantitative methods in geography became particularly influential in the discipline during the 1950s and 60s. These methods revitalized the discipline in many ways, allowing scientific testing of hypotheses and proposing scientific geographic theories and laws.

Geomatics

is concerned with the application of computers to the traditional spatial techniques used in

and

topography Topography is the study of the forms and features of land surfaces. The topography of an area may refer to the land forms and features themselves, or a description or depiction in maps. Topography is a field of geoscience and planetary sci ...

. Similar to the terms

geographic information science Geographic information science or geographical information science (GIScience or GISc) is the scientific discipline that studies geographic information, including how it represents phenomena in the real world, how it represents the way humans unders ...

and technical geography, geomatics emerged from the

quantitative revolution The quantitative revolution (QR) was a paradigm shift that sought to develop a more rigorous and systematic methodology for the discipline of geography. It came as a response to the inadequacy of regional geography to explain general spatial dynam ...

in geography in the mid-1950s. Today, geomatics methods include

spatial analysis Spatial analysis or spatial statistics includes any of the formal techniques which studies entities using their topological, geometric, or geographic properties. Spatial analysis includes a variety of techniques, many still in their early deve ...

, geographic information systems (GIS),

, and

global positioning system The Global Positioning System (GPS), originally Navstar GPS, is a satellite-based radionavigation system owned by the United States government and operated by the United States Space Force. It is one of the global navigation satellite sy ...

s (GPS). Geomatics has revitalized some geography departments, especially in Northern America, where the subject had a declining status during the 1950s. Because of this, many have proposed it may be a third branch in geography, in addition to physical and human.

Quantitative cartography

Cartography is the art, science, and technology of making maps. Cartographers study the Earth's surface representation 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 Cognitive psychology is the scientific study of mental processes such as attention, language use, memory, perception, problem solving, creativity, and reasoning. Cognitive psychology originated in the 1960s in a break from behaviorism, which ...

and

ergonomics Human factors and ergonomics (commonly referred to as human factors) is the application of psychological and physiological principles to the engineering and design of products, processes, and systems. Four primary goals of human factors learnin ...

to understand which symbols convey information about the Earth most effectively and

behavioural psychology Behaviorism is a systematic approach to understanding the behavior of humans and animals. It assumes that behavior is either a reflex evoked by the pairing of certain antecedent stimuli in the environment, or a consequence of that individual ...

to induce the readers of their maps to act on the information. They must learn

geodesy Geodesy ( ) is the Earth science of accurately measuring and understanding Earth's figure (geometric shape and size), orientation in space, and gravity. The field also incorporates studies of how these properties change over time and equivale ...

and fairly advanced mathematics to understand how the

shape of the Earth Figure of the Earth is a term of art in geodesy that refers to the size and shape used to model Earth. The size and shape it refers to depend on context, including the precision needed for the model. A sphere is a well-known historical approxim ...

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

Geographic information systems (GIS) deal with storing 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 Computer science is the study of computation, automation, and information. Computer science spans theoretical disciplines (such as algorithms, theory of computation, information theory, and automation) to Applied science, practical discipli ...

and

database In computing, a database is an organized collection of data stored and accessed electronically. Small databases can be stored on a file system, while large databases are hosted on computer clusters or cloud storage. The design of databases sp ...

systems. GIS has revolutionized the field of cartography: nearly all mapmaking is now done with the assistance of some form of

GIS software A GIS software program is a computer program to support the use of a geographic information system, providing the ability to create, store, manage, query, analyze, and visualize geographic data, that is, data representing phenomena for which lo ...

. The science of using GIS software and GIS techniques to represent, analyse, and predict the spatial relationships is called ''

'' (GISc).

Remote sensing

Remote sensing is the art, science, and technology of obtaining information about Earth's features from measurements made at a distance. Remotely sensed data comes in many forms, such as

satellite imagery Satellite images (also Earth observation imagery, spaceborne photography, or simply satellite photo) are images of Earth collected by imaging satellites operated by governments and businesses around the world. Satellite imaging companies sell ima ...

aerial photography Aerial photography (or airborne imagery) is the taking of photographs from an aircraft or other airborne platforms. When taking motion pictures, it is also known as aerial videography. Platforms for aerial photography include fixed-wing aircra ...

, and data obtained from hand-held sensors. Geographers increasingly use remotely sensed data to obtain information about the Earth's

land surface Terrain or relief (also topographical relief) involves the vertical and horizontal dimensions of land surface. The term bathymetry is used to describe underwater relief, while hypsometry studies terrain relative to sea level. The Latin wo ...

, 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 The electromagnetic spectrum is the range of frequencies (the spectrum) of electromagnetic radiation and their respective wavelengths and photon energies. The electromagnetic spectrum covers electromagnetic waves with frequencies ranging from ...

, and (e) facilitates studies of how features/areas change over time. Remotely sensed data may be analyzed independently or in conjunction with other digital data layers (e.g., in a geographic information system). Remote sensing aids in land use, land cover (LULC) mapping, by helping to determine both what is naturally occurring on a piece of land and what human activities are taking place on it.

Geostatistics

deal with

quantitative data Quantitative research is a research strategy that focuses on quantifying the collection and analysis of data. It is formed from a deductive approach where emphasis is placed on the testing of theory, shaped by empiricist and positivist philosop ...

analysis, specifically the application of a statistical methodology to the exploration of geographic phenomena. Geostatistics is used extensively in a variety of fields, including

hydrology Hydrology () is the scientific study of the movement, distribution, and management of water on Earth and other planets, including the water cycle, water resources, and environmental watershed sustainability. A practitioner of hydrology is calle ...

, geology, petroleum exploration, weather analysis,

urban planning Urban planning, also known as town planning, city planning, regional planning, or rural planning, is a technical and political process that is focused on the development and design of land use and the built environment, including air, water, ...

, logistics, and

epidemiology Epidemiology is the study and analysis of the distribution (who, when, and where), patterns and determinants of health and disease conditions in a defined population. It is a cornerstone of public health, and shapes policy decisions and evidenc ...

. The mathematical basis for geostatistics derives from

cluster analysis Cluster analysis or clustering is the task of grouping a set of objects in such a way that objects in the same group (called a cluster) are more similar (in some sense) to each other than to those in other groups (clusters). It is a main task of ...

linear discriminant analysis Linear discriminant analysis (LDA), normal discriminant analysis (NDA), or discriminant function analysis is a generalization of Fisher's linear discriminant, a method used in statistics and other fields, to find a linear combination of features ...

and non-parametric statistical tests, and a variety of other subjects. Applications of geostatistics rely heavily on geographic information systems, particularly for the

interpolation In the mathematical field of numerical analysis, interpolation is a type of estimation, a method of constructing (finding) new data points based on the range of a discrete set of known data points. In engineering and science, one often has a n ...

(estimate) of unmeasured points. Geographers are making notable contributions to the method of quantitative techniques.

Qualitative methods

Qualitative geography is descriptive rather than numerical or statistical in nature. They add context to concepts, and explore human concepts like beliefs and perspective that are difficult or impossible to quantify. Human geography is much more likely to employ qualitative methods than physical. Increasingly, technical geographers are attempting to employ GIS methods to qualitative datasets.

Qualitative cartography

Qualitative cartography employs many of the same software and techniques as quantitative. It may be employed to inform on map practices, or to visualize perspectives and ideas that are not strictly quantitative in nature.

Ethnography

Ethnographical research techniques are used by human geographers. In

cultural geography Cultural geography is a subfield within human geography. Though the first traces of the study of different nations and cultures on Earth can be dated back to ancient geographers such as Ptolemy or Strabo, cultural geography as academic study first ...

, there is a tradition of employing

qualitative research Qualitative research is a type of research that aims to gather and analyse non-numerical (descriptive) data in order to gain an understanding of individuals' social reality, including understanding their attitudes, beliefs, and motivation. This ...

techniques, also used in

anthropology Anthropology is the scientific study of humanity, concerned with human behavior, human biology, cultures, societies, and linguistics, in both the present and past, including past human species. Social anthropology studies patterns of behavi ...

and sociology.

Participant observation Participant observation is one type of data collection method by practitioner-scholars typically used in qualitative research and ethnography. This type of methodology is employed in many disciplines, particularly anthropology (incl. cultural an ...

and in-depth interviews provide human geographers with qualitative data.

History

The concept of geography is present in all cultures, and therefore the history of the discipline is a series of competing narratives, with concepts emerging at various points across space and time. The oldest known

world map A world map is a map of most or all of the surface of Earth. World maps, because of their scale, must deal with the problem of map projection, projection. Maps rendered in two dimensions by necessity distort the display of the three-dimensiona ...

s date back to

ancient Babylon ''Bābili(m)'' * sux, 𒆍𒀭𒊏𒆠 * arc, 𐡁𐡁𐡋 ''Bāḇel'' * syc, ܒܒܠ ''Bāḇel'' * grc-gre, Βαβυλών ''Babylṓn'' * he, בָּבֶל ''Bāvel'' * peo, 𐎲𐎠𐎲𐎡𐎽𐎢 ''Bābiru'' * elx, 𒀸𒁀𒉿𒇷 ''Babi ...

from the 9th century BC. The best known

Babylonia Babylonia (; Akkadian: , ''māt Akkadī'') was an ancient Akkadian-speaking state and cultural area based in the city of Babylon in central-southern Mesopotamia (present-day Iraq and parts of Syria). It emerged as an Amorite-ruled state c. ...

n world map, however, is the ''

Imago Mundi ''Imago Mundi'', or in full ''Imago Mundi: International Journal for the History of Cartography'', is a semiannual peer-reviewed academic journal about mapping, established in 1935 by Leo Bagrow. It covers the history of early maps, cartography, ...

'' of 600 BC. The map as reconstructed by

Eckhard Unger Eckhard Unger (Landsberg an der Warthe, 11 April 1884 – 24 July 1966) was a German assyriologist. Unger who was the curator of the Istanbul museum described the remains of Balawat Gates that are still in the Istanbul Museum. Unger was fully aw ...

shows

Babylon ''Bābili(m)'' * sux, 𒆍𒀭𒊏𒆠 * arc, 𐡁𐡁𐡋 ''Bāḇel'' * syc, ܒܒܠ ''Bāḇel'' * grc-gre, Βαβυλών ''Babylṓn'' * he, בָּבֶל ''Bāvel'' * peo, 𐎲𐎠𐎲𐎡𐎽𐎢 ''Bābiru'' * elx, 𒀸𒁀𒉿𒇷 ''Babi ...

on the

Euphrates The Euphrates () is the longest and one of the most historically important rivers of Western Asia. Tigris–Euphrates river system, Together with the Tigris, it is one of the two defining rivers of Mesopotamia ( ''the land between the rivers'') ...

, surrounded by a circular landmass showing

Assyria Assyria (Neo-Assyrian cuneiform: , romanized: ''māt Aššur''; syc, ܐܬܘܪ, ʾāthor) was a major ancient Mesopotamian civilization which existed as a city-state at times controlling regional territories in the indigenous lands of the A ...

Urartu Urartu (; Assyrian: ',Eberhard Schrader, ''The Cuneiform inscriptions and the Old Testament'' (1885), p. 65. Babylonian: ''Urashtu'', he, אֲרָרָט ''Ararat'') is a geographical region and Iron Age kingdom also known as the Kingdom of Va ...

, and several cities, in turn surrounded by a "bitter river" (

Oceanus In Greek mythology, Oceanus (; grc-gre, , Ancient Greek pronunciation: , also Ὠγενός , Ὤγενος , or Ὠγήν ) was a Titan son of Uranus and Gaia, the husband of his sister the Titan Tethys, and the father of the river gods a ...

), 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. In contrast to the ''Imago Mundi'', an earlier Babylonian

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. The ideas of

Anaximander Anaximander (; grc-gre, Ἀναξίμανδρος ''Anaximandros''; ) was a pre-Socratic Greek philosopher who lived in Miletus,"Anaximander" in ''Chambers's Encyclopædia''. London: George Newnes, 1961, Vol. 1, p. 403. a city of Ionia (in moder ...

(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 A gnomon (; ) is the part of a sundial that casts a shadow. The term is used for a variety of purposes in mathematics and other fields. History A painted stick dating from 2300 BC that was excavated at the astronomical site of Taosi is the ol ...

, the simple, yet efficient Greek instrument that allowed the early measurement of

latitude In geography, latitude is a coordinate that specifies the north– south position of a point on the surface of the Earth or another celestial body. Latitude is given as an angle that ranges from –90° at the south pole to 90° at the north pol ...

Thales Thales of Miletus ( ; grc-gre, Θαλῆς; ) was a Greek mathematician, astronomer, statesman, and pre-Socratic philosopher from Miletus in Ionia, Asia Minor. He was one of the Seven Sages of Greece. Many, most notably Aristotle, regarded him ...

is also credited with the prediction of eclipses. The foundations of geography can be traced to ancient cultures, such as the ancient, medieval, and early modern

Chinese Chinese can refer to: * Something related to China * Chinese people, people of Chinese nationality, citizenship, and/or ethnicity **''Zhonghua minzu'', the supra-ethnic concept of the Chinese nation ** List of ethnic groups in China, people of ...

. The

Greeks The Greeks or Hellenes (; el, Έλληνες, ''Éllines'' ) are an ethnic group and nation indigenous to the Eastern Mediterranean and the Black Sea regions, namely Greece, Cyprus, Albania, Italy, Turkey, Egypt, and, to a lesser extent, oth ...

, who were the first to explore geography as both art and science, achieved this through

Philosophy Philosophy (from , ) is the systematized study of general and fundamental questions, such as those about existence, reason, knowledge, values, mind, and language. Such questions are often posed as problems to be studied or resolved. Some ...

, and

Literature Literature is any collection of written work, but it is also used more narrowly for writings specifically considered to be an art form, especially prose fiction, drama, and poetry. In recent centuries, the definition has expanded to include ...

, or through

Mathematics Mathematics is an area of knowledge that includes the topics of numbers, formulas and related structures, shapes and the spaces in which they are contained, and quantities and their changes. These topics are represented in modern 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 Parmenides of Elea (; grc-gre, Παρμενίδης ὁ Ἐλεάτης; ) was a pre-Socratic Greek philosopher from Elea in Magna Graecia. Parmenides was born in the Greek colony of Elea, from a wealthy and illustrious family. His dates a ...

Pythagoras Pythagoras of Samos ( grc, Πυθαγόρας ὁ Σάμιος, Pythagóras ho Sámios, Pythagoras the Samos, Samian, or simply ; in Ionian Greek; ) was an ancient Ionians, Ionian Ancient Greek philosophy, Greek philosopher and the eponymou ...

Anaxagoras Anaxagoras (; grc-gre, Ἀναξαγόρας, ''Anaxagóras'', "lord of the assembly"; 500 – 428 BC) was a Pre-Socratic Greek philosopher. Born in Clazomenae at a time when Asia Minor was under the control of the Persian Empire, ...

was able to demonstrate that the profile of the Earth was circular by explaining

eclipse An eclipse is an astronomical event that occurs when an astronomical object or spacecraft is temporarily obscured, by passing into the shadow of another body or by having another body pass between it and the viewer. This alignment of three ce ...

s. 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. The first rigorous system of

latitude and longitude The geographic coordinate system (GCS) is a spherical or ellipsoidal coordinate system for measuring and communicating positions directly on the Earth as latitude and longitude. It is the simplest, oldest and most widely used of the various ...

lines is credited to

Hipparchus Hipparchus (; el, Ἵππαρχος, ''Hipparkhos''; BC) was a Greek astronomer, geographer, and mathematician. He is considered the founder of trigonometry, but is most famous for his incidental discovery of the precession of the equi ...

. He employed a

sexagesimal Sexagesimal, also known as base 60 or sexagenary, is a numeral system with sixty as its base. It originated with the ancient Sumerians in the 3rd millennium BC, was passed down to the ancient Babylonians, and is still used—in a modified form� ...

system that was derived from

Babylonian mathematics Babylonian mathematics (also known as ''Assyro-Babylonian mathematics'') are the mathematics developed or practiced by the people of Mesopotamia, from the days of the early Sumerians to the centuries following the fall of Babylon in 539 BC. Babyl ...

. The meridians were subdivided into 360°, with each degree further subdivided into 60 (

minutes Minutes, also known as minutes of meeting (abbreviation MoM), protocols or, informally, notes, are the instant written record of a meeting or hearing. They typically describe the events of the meeting and may include a list of attendees, a state ...

). To measure the longitude at different locations on Earth, he suggested using eclipses to determine the relative difference in time. The extensive mapping by the

Romans Roman or Romans most often refers to: *Rome, the capital city of Italy * Ancient Rome, Roman civilization from 8th century BC to 5th century AD *Roman people, the people of ancient Rome *''Epistle to the Romans'', shortened to ''Romans'', a lette ...

as they explored new lands would later provide a high level of information for

Ptolemy Claudius Ptolemy (; grc-gre, Πτολεμαῖος, ; la, Claudius Ptolemaeus; AD) was a mathematician, astronomer, astrologer, geographer, and music theorist, who wrote about a dozen scientific treatises, three of which were of importanc ...

to construct detailed

atlas An atlas is a collection of maps; it is typically a bundle of maps of Earth or of a region of Earth. Atlases have traditionally been bound into book form, but today many atlases are in multimedia formats. In addition to presenting geographic ...

es. He extended the work of

, using a grid system on his maps and adopting a length of 56.5 miles for a degree. From the 3rd century onwards,

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). Chinese geographers such as

Liu An Liú Ān (, c. 179–122 BC) was a Han dynasty Chinese prince, ruling the Huainan Kingdom, and an advisor to his nephew, Emperor Wu of Han (武帝). He is best known for editing the (139 BC) ''Huainanzi'' compendium of Daoist, Confucianist, and ...

Pei Xiu Pei Xiu (224–271), courtesy name Jiyan, was a Chinese cartographer, geographer, politician, and writer of the state of Cao Wei during the late Three Kingdoms period and Jin dynasty of China. He was very much trusted by Sima Zhao, and p ...

Jia Dan Jia Dan (, 730 – 805), courtesy name Dunshi () and formally Duke Yuanjing of Wei (), was a Chinese cartographer, military general, and politician from Cangzhou, Hebei during the Tang dynasty. Background Jia Dan was born in 730, during the reign ...

Shen Kuo Shen Kuo (; 1031–1095) or Shen Gua, courtesy name Cunzhong (存中) and pseudonym Mengqi (now usually given as Mengxi) Weng (夢溪翁),Yao (2003), 544. was a Chinese polymathic scientist and statesman of the Song dynasty (960–1279). Shen wa ...

Fan Chengda Fan Chengda (, 1126–1193), courtesy name Zhineng (), was a Chinese geographer, poet, and politician. Known as one of the best-known Chinese poets of the Song Dynasty, he served as a government official, and was an academic authority in geography, ...

Zhou Daguan Zhou Daguan (; French: Tcheou Ta-Kouan; c. 1270–?) was a Chinese diplomat of the Yuan dynasty of China, serving under Temür Khan (Emperor Chengzong of Yuan). He is most well known for his accounts of the customs of Cambodia and the Angkor tem ...

, and

Xu Xiake Xu Xiake (, January 5, 1587 – March 8, 1641), born Xu Hongzu (), courtesy name Zhenzhi (), was a Chinese travel writer and geographer of the Ming dynasty (1368–1644), known best for his famous geographical treatise, and noted for his bravery ...

wrote important treatises, yet by the 17th century advanced ideas and methods of Western-style geography were adopted in China. PtolemyWorldMap

During the

Middle Ages In the history of Europe, the Middle Ages or medieval period lasted approximately from the late 5th to the late 15th centuries, similar to the post-classical period of global history. It began with the fall of the Western Roman Empire a ...

, the

fall of the Roman empire The fall of the Western Roman Empire (also called the fall of the Roman Empire or the fall of Rome) was the loss of central political control in the Western Roman Empire, a process in which the Empire failed to enforce its rule, and its vas ...

led to a shift in the evolution of geography from Europe to the

Islamic world The terms Muslim world and Islamic world commonly refer to the Islamic community, which is also known as the Ummah. This consists of all those who adhere to the religious beliefs and laws of Islam or to societies in which Islam is practiced. In ...

Muslim geographers Medieval Islamic geography and cartography refer to the study of geography and cartography in the Muslim world during the Islamic Golden Age (variously dated between the 8th century and 16th century). Muslim scholars made advances to the map-maki ...

such as

Muhammad al-Idrisi Abu Abdullah Muhammad al-Idrisi al-Qurtubi al-Hasani as-Sabti, or simply al-Idrisi ( ar, أبو عبد الله محمد الإدريسي القرطبي الحسني السبتي; la, Dreses; 1100 – 1165), was a Muslim geographer, cartograp ...

produced detailed world maps (such as

Tabula Rogeriana The ''Nuzhat al-mushtāq fī ikhtirāq al-āfāq'' ( ar, نزهة المشتاق في اختراق الآفاق, lit. "The Book of Pleasant Journeys into Faraway Lands"), commonly known in the West as the ''Tabula Rogeriana'' (lit. "''The Book of ...

), while other geographers such as

Yaqut al-Hamawi Yāqūt Shihāb al-Dīn ibn-ʿAbdullāh al-Rūmī al-Ḥamawī (1179–1229) ( ar, ياقوت الحموي الرومي) was a Muslim scholar of Byzantine Greek ancestry active during the late Abbasid period (12th-13th centuries). He is known fo ...

Abu Rayhan Biruni Abu Rayhan Muhammad ibn Ahmad al-Biruni (973 – after 1050) commonly known as al-Biruni, was a Khwarazmian Iranian in scholar and polymath during the Islamic Golden Age. He has been called variously the "founder of Indology", "Father of Co ...

Ibn Battuta Abu Abdullah Muhammad ibn Battutah (, ; 24 February 13041368/1369),; fully: ; Arabic: commonly known as Ibn Battuta, was a Berbers, Berber Maghrebi people, Maghrebi scholar and explorer who travelled extensively in the lands of Afro-Eurasia, ...

, and

Ibn Khaldun Ibn Khaldun (; ar, أبو زيد عبد الرحمن بن محمد بن خلدون الحضرمي, ; 27 May 1332 – 17 March 1406, 732-808 AH) was an Arab The Historical Muhammad', Irving M. Zeitlin, (Polity Press, 2007), p. 21; "It is, of ...

provided detailed accounts of their journeys and the geography of the regions they visited. Turkish geographer

Mahmud al-Kashgari Mahmud ibn Husayn ibn Muhammed al-Kashgari, ''Maḥmūd ibnu 'l-Ḥusayn ibn Muḥammad al-Kāšġarī'', , tr, Kaşgarlı Mahmûd, ug, مەھمۇد قەشقىرى, ''Mehmud Qeshqiri'' / Мәһмуд Қәшқири uz, Mahmud Qashg'ariy / М ...

drew a world map on a linguistic basis, and later so did

Piri Reis Ahmet Muhiddin Piri ( 1465 – 1553), better known as Piri Reis ( tr, Pîrî Reis (military rank), Reis or ''Hacı Ahmet Muhittin Pîrî Bey''), was a Navigation, navigator, Geography in medieval Islam, geographer and Cartography, cartographer. ...

(

Piri Reis map The Piri Reis map is a world map compiled in 1513 by the Ottoman admiral and cartographer Piri Reis. Approximately one third of the map survives; it shows the western coasts of Europe and North Africa and the coast of Brazil with reasonable accu ...

). Further, Islamic scholars translated and interpreted the earlier works of the

and the

and established the

House of Wisdom The House of Wisdom ( ar, بيت الحكمة, Bayt al-Ḥikmah), also known as the Grand Library of Baghdad, refers to either a major Abbasid public academy and intellectual center in Baghdad or to a large private library belonging to the Abba ...

Baghdad Baghdad (; ar, بَغْدَاد , ) is the capital of Iraq and the second-largest city in the Arab world after Cairo. It is located on the Tigris near the ruins of the ancient city of Babylon and the Sassanid Persian capital of Ctesiphon ...

for this purpose. Abū Zayd al-Balkhī, originally from

Balkh ), named for its green-tiled ''Gonbad'' ( prs, گُنبَد, dome), in July 2001 , pushpin_map=Afghanistan#Bactria#West Asia , pushpin_relief=yes , pushpin_label_position=bottom , pushpin_mapsize=300 , pushpin_map_caption=Location in Afghanistan ...

, founded the "Balkhī school" of terrestrial mapping in

. Suhrāb, a late tenth century Muslim geographer accompanied a book of geographical coordinates, with instructions for making a rectangular world map with

equirectangular projection The equirectangular projection (also called the equidistant cylindrical projection or la carte parallélogrammatique projection), and which includes the special case of the plate carrée projection (also called the geographic projection, lat/lon ...

or cylindrical equidistant projection.

(976–1048) first described a polar equi-

azimuthal equidistant projection The azimuthal equidistant projection is an azimuthal map projection. It has the useful properties that all points on the map are at proportionally correct distances from the center point, and that all points on the map are at the correct azimut ...

of the

celestial sphere In astronomy and navigation, the celestial sphere is an abstract sphere that has an arbitrarily large radius and is concentric to Earth. All objects in the sky can be conceived as being projected upon the inner surface of the celestial sphere, ...

. 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 The Indian subcontinent is a list of the physiographic regions of the world, physiographical region in United Nations geoscheme for Asia#Southern Asia, Southern Asia. It is situated on the Indian Plate, projecting southwards into the Indian O ...

. He often combined astronomical readings and mathematical equations to develop methods of pin-pointing locations by recording degrees of

and

longitude Longitude (, ) is a geographic coordinate that specifies the east–west position of a point on the surface of the Earth, or another celestial body. It is an angular measurement, usually expressed in degrees and denoted by the Greek letter l ...

. He also developed similar techniques when it came to measuring the heights of mountains, depths of the

valley A valley is an elongated low area often running between Hill, hills or Mountain, mountains, which will typically contain a river or stream running from one end to the other. Most valleys are formed by erosion of the land surface by rivers ...

s, and expanse of the

horizon The horizon is the apparent line that separates the surface of a celestial body from its sky when viewed from the perspective of an observer on or near the surface of the relevant body. This line divides all viewing directions based on whether i ...

. He also discussed

and the

planetary habitability Planetary habitability is the measure of a planet's or a natural satellite's potential to develop and maintain environments hospitable to life. Life may be generated directly on a planet or satellite endogenously or be transferred to it from ...

of the Earth. He also calculated the

of Kath,

Khwarezm Khwarazm (; Old Persian: ''Hwârazmiya''; fa, خوارزم, ''Xwârazm'' or ''Xârazm'') or Chorasmia () is a large oasis region on the Amu Darya river delta in western Central Asia, bordered on the north by the (former) Aral Sea, on the ...

, using the maximum altitude of the Sun, and solved a complex

geodesic In geometry, a geodesic () is a curve representing in some sense the shortest path ( arc) between two points in a surface, or more generally in a Riemannian manifold. The term also has meaning in any differentiable manifold with a connection. ...

equation to accurately compute the

Earth's circumference Earth's circumference is the distance around Earth. Measured around the Equator, it is . Measured around the poles, the circumference is . Measurement of Earth's circumference has been important to navigation since ancient times. The first know ...

, which was close to modern values of the Earth's circumference. His estimate of 6,339.9 km for the

Earth radius Earth radius (denoted as ''R''🜨 or R_E) is the distance from the center of Earth to a point on or near its surface. Approximating the figure of Earth by an Earth spheroid, the radius ranges from a maximum of nearly (equatorial radius, deno ...

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 Abu Rayhan Muhammad ibn Ahmad al-Biruni (973 – after 1050) commonly known as al-Biruni, was a Khwarazmian Iranian in scholar and polymath during the Islamic Golden Age. He has been called variously the "founder of Indology", "Father of Co ...

developed a new method of using

trigonometric Trigonometry () is a branch of mathematics that studies relationships between side lengths and angles of triangles. The field emerged in the Hellenistic world during the 3rd century BC from applications of geometry to astronomical studies. ...

calculations based on the angle between a

plain In geography, a plain is a flat expanse of land that generally does not change much in elevation, and is primarily treeless. Plains occur as lowlands along valleys or at the base of mountains, as coastal plains, and as plateaus or uplands ...

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. Alexander von Humboldt-selfportrait

The European

Age of Discovery The Age of Discovery (or the Age of Exploration), also known as the early modern period, was a period largely overlapping with the Age of Sail, approximately from the 15th century to the 17th century in European history, during which seafarin ...

during the 16th and the 17th centuries, where many new lands were discovered and accounts by European explorers such as

Christopher Columbus Christopher Columbus * lij, Cristoffa C(or)ombo * es, link=no, Cristóbal Colón * pt, Cristóvão Colombo * ca, Cristòfor (or ) * la, Christophorus Columbus. (; born between 25 August and 31 October 1451, died 20 May 1506) was a ...

Marco Polo Marco Polo (, , ; 8 January 1324) was a Venetian merchant, explorer and writer who travelled through Asia along the Silk Road between 1271 and 1295. His travels are recorded in ''The Travels of Marco Polo'' (also known as ''Book of the Marv ...

, and

James Cook James Cook (7 November 1728 Old Style date: 27 October – 14 February 1779) was a British explorer, navigator, cartographer, and captain in the British Royal Navy, famous for his three voyages between 1768 and 1779 in the Pacific Ocean an ...

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 meridians should be was only part of the problem. It was left to

John Harrison John Harrison ( – 24 March 1776) was a self-educated English Carpentry, carpenter and clockmaker who invented the marine chronometer, a long-sought-after device for solving the History of longitude, problem of calculating longitude while at s ...

to solve it by inventing the chronometer H-4 in 1760, and later in 1884 for the

International Meridian Conference The International Meridian Conference was a conference held in October 1884 in Washington, D.C., in the United States, to determine a prime meridian for international use. The conference was held at the request of U.S. President Chester A. ...

to adopt by convention the

Greenwich meridian The historic prime meridian or Greenwich meridian is a geographical reference line that passes through the Royal Observatory, Greenwich, Royal Observatory, Greenwich, in London, England. The modern IERS Reference Meridian widely used today ...

as zero meridians. The 18th and 19th centuries were the times when geography became recognized as a discrete

academic discipline An academy ( Attic Greek: Ἀκαδήμεια; Koine Greek Ἀκαδημία) is an institution of secondary or tertiary higher learning (and generally also research or honorary membership). The name traces back to Plato's school of philosophy ...

, and became part of a typical university curriculum in Europe (especially Paris and

Berlin Berlin ( , ) is the capital and largest city of Germany by both area and population. Its 3.7 million inhabitants make it the European Union's most populous city, according to population within city limits. One of Germany's sixteen constitue ...

). The development of many geographic societies also occurred during the 19th century, with the foundations of the

Société de Géographie The Société de Géographie (; ), is the world's oldest geographical society. It was founded in 1821 as the first Geographic Society. Since 1878, its headquarters have been at 184 Boulevard Saint-Germain, Paris. The entrance is marked by two gig ...

in 1821, the

Royal Geographical Society The Royal Geographical Society (with the Institute of British Geographers), often shortened to RGS, is a learned society and professional body for geography based in the United Kingdom. Founded in 1830 for the advancement of geographical scien ...

in 1830,

Russian Geographical Society The Russian Geographical Society (russian: Ру́сское географи́ческое о́бщество «РГО»), or RGO, is a learned society based in Saint Petersburg, Russia. It promotes geography, exploration and nature protection wi ...

in 1845,

American Geographical Society The American Geographical Society (AGS) is an organization of professional geographers, founded in 1851 in New York City. Most fellows of the society are Americans, but among them have always been a significant number of fellows from around the ...

in 1851, and the

National Geographic Society The National Geographic Society (NGS), headquartered in Washington, D.C., United States, is one of the largest non-profit scientific and educational organizations in the world. Founded in 1888, its interests include geography, archaeology, and ...

in 1888. The influence of

Immanuel Kant Immanuel Kant (, , ; 22 April 1724 – 12 February 1804) was a German philosopher and one of the central Enlightenment thinkers. Born in Königsberg, Kant's comprehensive and systematic works in epistemology, metaphysics, ethics, and ...

Alexander von Humboldt Friedrich Wilhelm Heinrich Alexander von Humboldt (14 September 17696 May 1859) was a German polymath, geographer, naturalist, explorer, and proponent of Romantic philosophy and science. He was the younger brother of the Prussian minister, p ...

Carl Ritter Carl Ritter (August 7, 1779September 28, 1859) was a German geographer. Along with Alexander von Humboldt, he is considered one of the founders of modern geography. From 1825 until his death, he occupied the first chair in geography at the Univer ...

, and

Paul Vidal de la Blache #REDIRECT Paul Vidal de La Blache #REDIRECT Paul Vidal de La Blache {{redirect category shell, {{R from move{{R from other capitalisation ...

{{redirect category shell, {{R from move{{R from other capitalisation ...

Introduction

Core concepts

Space

Place

Time

Scale

Laws of geography

Sub-disciplines

Four traditions of geography

Spatial or locational tradition

Area studies or regional tradition

Human-Environment interaction tradition

Earth science tradition

Branches of geography

Physical

Human

Technical

Related fields

Techniques

Quantitative methods

Geomatics

Quantitative cartography

Geographic information systems

Remote sensing

Geostatistics

Qualitative methods

Qualitative cartography

Ethnography

History

Notable geographers

Institutions and societies

Publications

See also

References

External links