Department of TransportationRelated Research. A number of DOT assessment efforts that are not formally part of the USGCRP will help to improve understanding of the human dimensions of global change in the transportation sector. The DOT Federal Highway Administration worked with the National Research Council's Transportation Research Board (TRB) to support a study on the long-term effects of motor vehicle transportation on climate and ecosystems. This work focused on climate change and biodiversity, and emphasized the global nature of the problem. The National Cooperative Highway and Transit Research Programs were also involved. The results of this effort are summarized in TRBÕs Special Report #251, Toward a Sustainable Future. The Travel Model Improvement Program (TMIP) is supporting some initial efforts to strengthen the interaction between land use and transportation forecasting in the infrastructure planning process. TMIP is a cooperative venture of DOT, DOE, and EPA.