A decomposition analysis is used to investigate the main factors influencing the CO2 emissions of European transport activities for the period 2001-2008. The decomposition method developed by Sun [1] has been used to investigate the carbon dioxide emissions intensity, the energy intensity, the structural changes and the economy activity growth effects for the water and the aviation transport sectors. The analysis is based on Eurostat data and results are presented for 14 Member States, Norway and EU27. Results indicate that economic growth has been the main factor behind the carbon dioxide emissions increase in EU27 both for water and aviation transport activities. (C) 2012 Elsevier Ltd. All rights reserved.