The Geography of Transport Systems

Previous Next


Attributes of the Terrestrial Space


Absolute and Relative Barriers


The Geographical Space of Maritime Transportation


Polar Shipping Routes
Detailed PDF Map


Global Wind Patterns


Seasonal Variations of Global Wind Patterns

th_greatcircle.gif (2308 bytes)
The Great Circle Distance
Detailed PDF Map


Great Circle Distance Calculator


Site and Situation

th_concplace.gif (1578 bytes)
The Spatial Structure and Transportation


Transportation Networks and Geographical Specialization


Transportation Networks and Geographical Segregation


Space / Time Convergence


Regional Space / Time Convergence (London - Edinburgh, New York - Boston)


Days Required to Circumnavigate the Globe


Mail Delivery Times between New York and San Francisco, 1840-2000 (in days)


Cumulative Distribution of per Capita Trip Rate for all Modes by Trip Distance, 1995


Space / Time Convergence of the World Transport System

th_meantraveltime.gif (1466 bytes)
Home-to-Work Commute Profile, United States, 1983-2003


Great Circle Distance Calculator (Excel)


Chapter 1 - Concepts (PowerPoint)

Transportation and Space

Author : Dr. Jean-Paul Rodrigue and Dr. Claude Comtois

1. Physical Constraints

Transport geography is concerned with movements that take place over space. The physical features of this space impose major constraints on transportation systems, in terms of what mode can be used, the extent of the service, its costs, capacity and reliability. Three basic spatial constraints of the terrestrial space can be identified:

From a geometrical standpoint, the sphericity of the earth determines the great circle distance (Great Circle Distance Calculator); the least distance line between two points on a sphere. This feature explains the paths followed by major intercontinental maritime and air routes.

2. Transportation and the Spatial Structure

The concepts of site and situation are fundamental to geography and to transportation. While the site refers to the geographical characteristics of a specific location, its situation concerns its relationships in regard to other locations. Thus, all locations are relative to one another but situation is not a constant attribute as transportation developments change levels of accessibility, and thus the relations between locations. The development of a location reflects the cumulative relationships between transport infrastructure, economic activities and the built-environment. The following factors are particularly important in shaping the spatial structure:

Many contemporary transportation networks are inherited from the past, notably transport infrastructures. Even if over the last two hundred years new technologies have revolutionized transportation in terms of speed, capacity and efficiency, the spatial structure of many networks has not much changed. This inertia in the spatial structure of some transportation networks can be explained by two major factors:

While physical and historical considerations are at play, the introduction of new transport technology or the addition of new transport infrastructure are leading to a transformation of existing networks. Recent developments in transport systems such as container shipping, jumbo aircrafts and the extensive application of information technology to transport management have created a new transport environment and a new spatial structure. These transport infrastructures have intensified global interactions and modified the relative location of places. In this highly dynamic context, two processes are taking place at the same time:

The continuous evolution of transportation technology may not necessarily have expected effects on the spatial structure, as two forces are at play; concentration and dispersion. A common myth tends to relate transportation solely as a force of dispersion, favoring the spread of activities in space. This is not always the case. In numerous instances, transportation is a force of concentration, notably for business activities. Since transport infrastructures are generally expensive to build, they are established first to service the most important locations. Even if it was a strong factor of dispersion, the automobile has also favored the concentration of several activities at specific places and in large volumes. Shopping centers are a relevant example of this process where central locations emerge in a dispersed setting.

3. Space / Time Relationships

One of the most basic relationships of transportation involves how much space can be overcome within a given amount of time. The faster the mode, the larger the distance that can be overcome within the same amount of time. Transportation, notably improvements in transport systems, changes the relationship between time and space. When this relationship involves easier, faster and cheaper access between places, this result is defined as a space / time convergence because the amount of space that can be overcome for a similar amount of time increases significantly. Significant regional and continental gains were achieved during the 18th and 19th centuries with the establishment of national and continental railway systems as well as with the growth of maritime shipping, a process which continued into the 20th century with air and road transport systems. The outcome has been significant differences in space / time relationships, mainly between developed and developing countries, reflecting differences in the efficiency of transport systems.

At the international level, globalization processes have been supported by improvements in transport technology. The result of more than 200 years of technological improvements has been a space / time collapse of global proportions in addition to the regional and continental processes previously mentioned. This enabled the extended exploitation of the advantages of the global market, notably in terms of resources and labor. Significant reductions in transport and communication costs occurred concomitantly. There is thus a relationship between the rate of a space / time collapse on the integration of a region in global trade. Five major factors are of particular relevance in this process:

However, space / time convergence can also be inverted under specific circumstances, which means that a process of space / time divergence takes place. For instance, congestion is increasing in many metropolitan areas, implying additional delays for activities such as commuting. Traffic in congested urban areas is moving at the same speed that it did one hundred years ago on horse carriages. Air transportation, despite having dramatically contributed to the space / time convergence is also experiencing growing delays. Flight times are getting longer between many destinations, mainly because of takeoff, landing and gate access delays. Airlines are simply posting longer flight times to factor in congestion. An express mail package flown from Washington to Boston in about an hour (excluding delays at takeoff and landing due to airport congestion) can have an extra one hour delay as it is carried from Logan Airport to downtown Boston, a distance of only two miles. More stringent security measures at airports have also imposed additional delays, which tends to penalize more short distance flights. The "last mile" can be the longest in many transport segments.

Copyright © 1998-2008, Dr. Jean-Paul Rodrigue, Dept. of Economics & Geography, Hofstra University. For personal or classroom use ONLY. This material (including graphics) is not public domain and cannot be published, in whole or in part, in ANY form (printed or electronic) and on any media without consent. Permission MUST be requested prior to use.

04/23/08