Mobility is fundamental to economic and social activities such as commuting, manufacturing, or supplying energy. Each movement has an origin, a potential set of intermediate locations, a destination, and a nature which is linked with geographical attributes. Transport systems composed of infrastructures, modes and terminals are so embedded in the socio-economic life of individuals, institutions and corporations that they are often invisible to the consumer. This is paradoxical as the perceived invisibility of transportation is derived from its efficiency. Understanding how mobility is linked with geography is main the purpose of this book. The third edition of The Geography of Transport Systems has been revised and updated to provide an overview of the spatial aspects of transportation. This text provides greater discussion of security, energy, green logistics, as well as new and updated case studies, a revised content structure, and new figures. Each chapter covers a specific conceptual dimension including networks, modes, terminals, freight transportation, urban transportation and environmental impacts. A final chapter contains core methodologies linked with transport geography such as accessibility, spatial interactions, graph theory and Geographic Information Systems for transportation (GIS-T). This book provides a comprehensive and accessible introduction to the field, with a broad overview of its concepts, methods, and areas of application. The accompanying website for this text contains a useful additional material, including digital maps, PowerPoint slides, databases, and links to further reading and websites. The website can be accessed at: http://people.hofstra.edu/geotrans This text is an essential resource for undergraduates studying transport geography, as well as those interest in economic and urban geography, transport planning and engineering.

The process of economic development is characterized by substantial reallocations of resources across sectors. In this paper, we construct a multi-sector model in which there are barriers to the movement of labor from low-productivity traditional agriculture to modern sectors. With the barrier in place, we show that improvements in productivity in modern sectors (including agriculture) or reductions in transportation costs may lead to a rise in agricultural employment and through terms-oftrade effects may harm subsistence farmers if the traditional subsistence sector is larger than a critical level. This suggests that policy advice based on the earlier literature needs to be revised. Reducing barriers to mobility (through reductions in the cost of skill acquisition and institutional changes) and improving the productivity of subsistence farmers needs to precede policies designed to increase the productivity of modern sectors or decrease transportation costs.

Global warming continues to gain importance on the international agenda and calls for action are heightening. Yet, there is still controversy over what must be done and what is needed to proceed. Policy Implications of Greenhouse Warming describes the information necessary to make decisions about global warming resulting from atmospheric releases of radiatively active trace gases. The conclusions and recommendations include some unexpected results. The distinguished authoring committee provides specific advice for U.S. policy and addresses the need for an international response to potential greenhouse warming. It offers a realistic view of gaps in the scientific understanding of greenhouse warming and how much effort and expense might be required to produce definitive answers. The book presents methods for assessing options to reduce emissions of greenhouse gases into the atmosphere, offset emissions, and assist humans and unmanaged systems of plants and animals to adjust to the consequences of global warming.

The Transportation Research Board (TRB) and the Division on Earth and Life Studies (DELS) have released the pre-publication version of TRB Special Report 290, The Potential Impacts of Climate Change on U.S. Transportation, which explores the consequences of climate change for U.S. transportation infrastructure and operations. The report provides an overview of the scientific consensus on the current and future climate changes of particular relevance to U.S. transportation, including the limits of present scientific understanding as to their precise timing, magnitude, and geographic location; identifies potential impacts on U.S. transportation and adaptation options; and offers recommendations for both research and actions that can be taken to prepare for climate change. The book also summarizes previous work on strategies for reducing transportation-related emissions of carbon dioxide--the primary greenhouse gas--that contribute to climate change. Five commissioned papers used by the committee to help develop the report, a summary of the report, and a National Academies press release associated with the report are available online. DELS, like TRB, is a division of the National Academies, which include the National Academy of Sciences, National Academy of Engineering, Institute of Medicine, and National Research Council.