Time-Geography

Time-geography refers to a set of concepts and a way of thinking that offer a notational system to describe and analyze individuals’ and populations’ existence, coexistence, constraints, and conflicts in time-space. The time-geographic approach was originally presented in the late 1960s by Torsten Hägerstrand, a well-known professor of human geography at Lund University, Sweden. Time-geography captures complex processes of change on different scales in time and space and is therefore useful for analyzing various topics and problems.

The time-geographic lines of thought are directly linked to Hägerstrand's experiences as the son of an elementary schoolteacher who sought to impart “knowledge about their home district.” Hägerstrand found the prevailing academic thinking, which grouped phenomena according to their degree of similarity, to be deficient; his alternative approach was to group phenomena according to their proximity in time and space.

The theoretical roots of time-geography are found in Hägerstrand's thorough empirical fieldwork in Asby parish in Southern Sweden. He and his wife spent several summers biking there searching for houses (or their remains) abandoned by emigrants to the United States during the 19th century. Then, the dominant understanding [Page 2838]among researchers was that each empty house had been the home of an emigrant family. The Asby fieldwork made Hägerstrand question this view, since the resource base surrounding the empty houses was too poor for subsistence—much less for buying a ticket to America. By studying the population in the Asby parish books, individual by individual, he concluded that the emigrant families were those that were relatively well-off but still too poor to find in Asby a place better than their American dream. They sold their houses, and a chain of movements started, with poorer families moving from low-income houses to better ones. As a result, farms that operated under the subsistence level were left empty. Following the individual inhabitants of the houses was the only way to find out who left which house for a better life in America. Houses and people come in many different kinds, but they must be considered together to reevaluate the dominating theory.

In time-geography, the two dimensions of time and space (place, region) are united into a time-space in which processes involving different phenomena can be discerned, irrespective of whether such phenomena are living or nonliving. Each individual is born or created at some point in time, exists during a time period, and dies. This process describes a time-space biography of an individual human being, but since time-geography also includes nonliving phenomena, the more general concept of individual path (trajectory) is introduced. Individuals of the same bounded region (time-space) constitute a population. A bounded region can be defined at different scales: the globe as a whole, a continent, a country, or any locality on the globe. In each region in time-space, individuals (from one or more populations) get in touch with other individuals, and when they move (or are moved), they decouple from one bundle of individuals with whom they were in touch and couple with another bundle. Time-geography facilitates analysis of opportunities for individuals to get in touch with one another and of the constraints on and consequences of such coupling, and it provides tools for dynamic life cycle analysis. For example, environmental problems may be described by the extraction (decoupling) of raw materials in a region and their transportation to a place where they are manufactured (put into new combinations). Manufacturing is performed at a place by labor, using tools and machines according to procedures that steer the work process, constituting a pocket of local order. Then the product is decoupled from the manufacturing location, transported, and sold. Through the sale, the output is coupled with the customer, who uses the product for reaching the goals of his or her projects. Eventually, the output is worn out, decoupled from the customer, and put in touch with other worn-out individual products at a waste collection center or maybe recycled.

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