Transportation research trends in environmental issues: a literature review of methodology and key subjects

Environmental issues have been a popular topic in various academic research areas including transportation. The aim of this paper is to identify major environmental research topics and research methods in the transportation field and thereby explore possible global research agenda. This paper selected a total of 1,291 papers from 51 journals based on keywords including both transport and environment. The literature survey shows that the number of environmental issue papers published in transportation journals has been growing significantly since 2007. Greenhouse gas emission is among the hottest topic in our literature survey. Little environmental research was conducted regarding maritime transport, as compared to passenger, land and aviation sectors. In terms of popular methodologies adopted to tackle environmental issues in the transportation journals, the top three methods are emission analysis, survey and simulation. There is plenty of room in conducting future transportation research in environmental topics, particularly in the maritime field.