Economic growth and transport: on the road to sustainability

Transport sustainability is an essential driving force towards achieving sustainable development. In particular, greenhouse gas (GHG) reduction policies cannot overlook the growing importance of the transport sector as economies expand. In this context, it is important to assess the relationship between carbon dioxide (CO2) emissions from the transport sector and economic growth, in order to design adequate transport policies. This paper tests the stated relationship for the Portuguese transport sector, using a non-linear cointegration methodology for the first time in this field. The main conclusion is that gross domestic product (GDP) and CO2 emissions from transport exhibit an increasing monotonic relationship, indicating that economic growth per se will be insufficient to mitigate the emissions. Therefore, it is necessary to search for concrete public policies that can influence both passenger travel behaviour and freight mobility plans, so as to reduce CO2 emissions without compromising economic development.