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. [1] Time geography "is not a subject area per se", [2] but rather an integrative ontological framework and visual language in which space and time are basic dimensions of analysis of dynamic processes. Time geography was originally developed by human geographers, but today it is applied in multiple fields related to transportation, regional planning, geography, anthropology, time-use research, ecology, environmental science, and public health. [3] According to Swedish geographer Bo Lenntorp: "It is a basic approach, and every researcher can connect it to theoretical considerations in her or his own way." [4]
The Swedish geographer Torsten Hägerstrand created time geography in the mid-1960s based on ideas he had developed during his earlier empirical research on human migration patterns in Sweden. [5] He sought "some way of finding out the workings of large socio-environmental mechanisms" using "a physical approach involving the study of how events occur in a time-space framework". [6] Hägerstrand was inspired in part by conceptual advances in spacetime physics and by the philosophy of physicalism. [7]
Hägerstrand's earliest formulation of time geography informally described its key ontological features: "In time-space the individual describes a path " within a situational context; "life paths become captured within a net of constraints, some of which are imposed by physiological and physical necessities and some imposed by private and common decisions". [8] "It would be impossible to offer a comprehensive taxonomy of constraints seen as time-space phenomena", Hägerstrand said, but he "tentatively described" three important classes of constraints:
Hägerstrand illustrated these concepts with novel forms of graphical notation (inspired in part by musical notation), [10] such as:
While this innovative visual language is an essential feature of time geography, Hägerstrand's colleague Bo Lenntorp emphasized that it is the product of an underlying ontology, and "not the other way around. The notation system is a very useful tool, but it is a rather poor reflection of a rich world-view. In many cases, the notational apparatus has been the hallmark of time geography. However, the underlying ontology is the most important feature." [12] Time geography is not only about time-geographic diagrams, just as music is not only about musical notation. Hägerstrand later explained: "What is briefly alluded to here is a 4-dimensional world of forms. This cannot be completely graphically depicted. On the other hand one ought to be able to imagine it with sufficient clarity for it to be of guidance in empirical and theoretical research." [13]
By 1981, geographers Nigel Thrift and Allan Pred were already defending time geography against those who would see it "merely as a rigid descriptive model of spatial and temporal organization which lends itself to accessibility constraint analysis (and related exercises in social engineering)." [14] They argued that time geography is not just a model of constraints; it is a flexible and evolving way of thinking about reality that can complement a wide variety of theories and research methods. In the decades since then, Hägerstrand and others have made efforts to expand his original set of concepts. [15] By the end of his life, Hägerstrand had ceased using the phrase "time geography" to refer to this way of thinking and instead used words like topoecology. [16]
Since the 1980s, time geography has been used by researchers in the social sciences, [18] the biological sciences, [19] and in interdisciplinary fields.
In 1993, British geographer Gillian Rose noted that "time-geography shares the feminist interest in the quotidian paths traced by people, and again like feminism, links such paths, by thinking about constraints, to the larger structures of society." [20] However, she noted that time geography had not been applied to issues important to feminists, and she called it a form of "social science masculinity". [21] Over the following decades, feminist geographers have revisited time geography and have begun to use it as a tool to address feminist issues. [22]
GIS software has been developed to compute and analyze time-geographic problems at a variety of spatial scales. Such analyses have used different types of network datasets (such as walking networks, highway networks, and public transit schedules) as well as a variety of visualization strategies. [23] Specialized software such as GeoTime has been developed to facilitate time-geographic visualization and visual analytics.
Time geography has also been used as a form of therapeutic assessment in mental health. [24]
Benjamin Bach and colleagues have generalized the space-time cube into a framework for temporal data visualization that applies to all data that can be represented in two dimensions plus time. [25]
In the COVID-19 pandemic, time geography approaches were applied to identify close contacts. [26] The pandemic imposed restrictions on the physical mobility of humans, which invited new applications of time geography in the increasingly virtualized post-Covid era. [27]
Human geography or anthropogeography is the branch of geography which studies spatial relationships between human communities, cultures, economies, and their interactions with the environment, examples of which include urban sprawl and urban redevelopment. It analyzes spatial interdependencies between social interactions and the environment through qualitative and quantitative methods. This multidisciplinary approach draws from sociology, anthropology, economics, and environmental science, contributing to a comprehensive understanding of the intricate connections that shape lived spaces.
Feminist geography is a sub-discipline of human geography that applies the theories, methods, and critiques of feminism to the study of the human environment, society, and geographical space. Feminist geography emerged in the 1970s, when members of the women's movement called on academia to include women as both producers and subjects of academic work. Feminist geographers aim to incorporate positions of race, class, ability, and sexuality into the study of geography. The discipline was a target for the hoaxes of the grievance studies affair.
Torsten Hägerstrand was a Swedish geographer. He is known for his work on migration, cultural diffusion and time geography.
Historical geography is the branch of geography that studies the ways in which geographic phenomena have changed over time. In its modern form, it is a synthesizing discipline which shares both topical and methodological similarities with history, anthropology, ecology, geology, environmental studies, literary studies, and other fields. Although the majority of work in historical geography is considered human geography, the field also encompasses studies of geographic change which are not primarily anthropogenic. Historical geography is often a major component of school and university curricula in geography and social studies. Current research in historical geography is being performed by scholars in more than forty countries.
Spatial analysis is any of the formal techniques which studies entities using their topological, geometric, or geographic properties. Spatial analysis includes a variety of techniques using different analytic approaches, especially spatial statistics. It may be applied in fields as diverse as astronomy, with its studies of the placement of galaxies in the cosmos, or to chip fabrication engineering, with its use of "place and route" algorithms to build complex wiring structures. In a more restricted sense, spatial analysis is geospatial analysis, the technique applied to structures at the human scale, most notably in the analysis of geographic data. It may also be applied to genomics, as in transcriptomics data.
The modifiable areal unit problem (MAUP) is a source of statistical bias that can significantly impact the results of statistical hypothesis tests. MAUP affects results when point-based measures of spatial phenomena are aggregated into spatial partitions or areal units as in, for example, population density or illness rates. The resulting summary values are influenced by both the shape and scale of the aggregation unit.
Children's geographies is an area of study within human geography and childhood studies which involves researching the places and spaces of children's lives.
Friction of distance is a core principle of geography that states that movement incurs some form of cost, in the form of physical effort, energy, time, and/or the expenditure of other resources, and that these costs are proportional to the distance traveled. This cost is thus a resistance against movement, analogous to the effect of friction against movement in classical mechanics. The subsequent preference for minimizing distance and its cost underlies a vast array of geographic patterns from economic agglomeration to wildlife migration, as well as many of the theories and techniques of spatial analysis, such as Tobler's first law of geography, network routing, and cost distance analysis. To a large degree, friction of distance is the primary reason why geography is relevant to many aspects of the world, although its importance has been decreasing with the development of transportation and communication technologies.
In the context of spatial analysis, geographic information systems, and geographic information science, a field is a property that fills space, and varies over space, such as temperature or density. This use of the term has been adopted from physics and mathematics, due to their similarity to physical fields (vector or scalar) such as the electromagnetic field or gravitational field. Synonymous terms include spatially dependent variable (geostatistics), statistical surface ( thematic mapping), and intensive property (physics and chemistry) and crossbreeding between these disciplines is common. The simplest formal model for a field is the function, which yields a single value given a point in space (i.e., t = f(x, y, z) )
Marxist geography is a strand of critical geography that uses the theories and philosophy of Marxism to examine the spatial relations of human geography. In Marxist geography, the relations that geography has traditionally analyzed — natural environment and spatial relations — are reviewed as outcomes of the mode of material production. To fully understand geographical relations, on this view, the social structure must also be examined. Marxist geography attempts to change the basic structure of society.
Geography is the study of the lands, features, inhabitants, and phenomena of Earth. 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. Geography has been called "a bridge between natural science and social science disciplines."
Quantitative geography is a subfield and methodological approach to geography that develops, tests, and uses scientific, mathematical, and statistical methods to analyze and model geographic phenomena and patterns. It aims to explain and predict the distribution and dynamics of human and physical geography through the collection and analysis of quantifiable data. The approach quantitative geographers take is generally in line with the scientific method, where a falsifiable hypothesis is generated, and then tested through observational studies. This has received criticism, and in recent years, quantitative geography has moved to include systematic model creation and understanding the limits of their models. This approach is used to study a wide range of topics, including population demographics, urbanization, environmental patterns, and the spatial distribution of economic activity. The methods of quantitative geography are often contrasted by those employed by qualitative geography, which is more focused on observing and recording characteristics of geographic place. However, there is increasing interest in using combinations of both qualitative and quantitative methods through mixed-methods research to better understand and contextualize geographic phenomena.
Anne Buttimer was an Irish geographer. She was emeritus professor of geography at University College, Dublin.
The second law of geography, according to Waldo Tobler, is "the phenomenon external to a geographic area of interest affects what goes on inside." This is an extension of his first. He first published it in 1999 in reply to a paper titled "Linear pycnophylactic reallocation comment on a paper by D. Martin" and then again in response to criticism of his first law of geography titled "On the First Law of Geography: A Reply." Much of this criticism was centered on the question of if laws were meaningful in geography or any of the social sciences. In this document, Tobler proposed his second law while recognizing others have proposed other concepts to fill the role of 2nd law. Tobler asserted that this phenomenon is common enough to warrant the title of 2nd law of geography. Unlike Tobler's first law of geography, which is relatively well accepted among geographers, there are a few contenders for the title of the second law of geography. Tobler's second law of geography is less well known but still has profound implications for geography and spatial analysis.
Technical geography is the branch of geography that involves using, studying, and creating tools to obtain, analyze, interpret, understand, and communicate spatial information.
The uncertain geographic context problem or UGCoP is a source of statistical bias that can significantly impact the results of spatial analysis when dealing with aggregate data. The UGCoP is very closely related to the Modifiable areal unit problem (MAUP), and like the MAUP, arises from how we divide the land into areal units. It is caused by the difficulty, or impossibility, of understanding how phenomena under investigation in different enumeration units interact between enumeration units, and outside of a study area over time. It is particularly important to consider the UGCoP within the discipline of time geography, where phenomena under investigation can move between spatial enumeration units during the study period. Examples of research that needs to consider the UGCoP include food access and human mobility.
The Modified Temporal Unit Problem (MTUP) is a source of statistical bias that occurs in time series and spatial analysis when using temporal data that has been aggregated into temporal units. In such cases, choosing a temporal unit can affect the analysis results and lead to inconsistencies or errors in statistical hypothesis testing.
Qualitative geography is a subfield and methodological approach to geography focusing on nominal data, descriptive information, and the subjective and interpretive aspects of how humans experience and perceive the world. Often, it is concerned with understanding the lived experiences of individuals and groups and the social, cultural, and political contexts in which those experiences occur. Thus, qualitative geography is traditionally placed under the branch of human geography; however, technical geographers are increasingly directing their methods toward interpreting, visualizing, and understanding qualitative datasets, and physical geographers employ nominal qualitative data as well as quanitative. Furthermore, there is increased interest in applying approaches and methods that are generally viewed as more qualitative in nature to physical geography, such as in critical physical geography. While qualitative geography is often viewed as the opposite of quantitative geography, the two sets of techniques are increasingly used to complement each other. Qualitative research can be employed in the scientific process to start the observation process, determine variables to include in research, validate results, and contextualize the results of quantitative research through mixed-methods approaches.
The neighborhood effect averaging problem or NEAP delves into the challenges associated with understanding the influence of aggregating neighborhood-level phenomena on individuals when mobility-dependent exposures influence the phenomena. The problem confounds the neighbourhood effect, which suggests that a person's neighborhood impacts their individual characteristics, such as health. It relates to the boundary problem, in that delineated neighborhoods used for analysis may not fully account for an individual's activity space if the borders are permeable, and individual mobility crosses the boundaries. The term was first coined by Mei-Po Kwan in the peer-reviewed journal "International Journal of Environmental Research and Public Health" in 2018.