An operational activity-based method to estimate CO2 emissions from container shipping considering empty container repositioning

► An operational activity-based method is developed to estimate CO2 emissions from container shipping. ► The method is compared to the traditional aggregated activity-based method based on two case studies. ► The paper shows that the aggregated method can overestimate CO2 emissions and the operational activity-based method is more appropriate. ► It demonstrates that high port handling capacity and efficient empty container repositioning can reduce emissions in seaborne transportation.