Feature Report: Sustainable Mobility

2 items of content in this feature report



The Global Transportation Sector: CO2 Emissions on the Rise

Economic globalization, higher living standards and the boom in tourism have spurred an increase in passenger and freight volumes since the end of the 20th century, a trend that is expected to continue through to 2050. The transportation sector is currently responsible for the fastest growth in CO2 emissions. 

Container ships are one illustration of the expansion of intercontinental trade. ©SHUTTERSTOCK

The global transportation sector is divided into two segments:

  • Commercial freight: This segment is expanding rapidly as a result of the rise in trade and the diversification of product value chains. Products are no longer manufactured at a single location but are usually made from components produced at different factories around the world. Freight is measured in tonne-kilometers, that is, the number of metric tons of freight transported multiplied by the number of kilometers traveled.
  • Passenger: This segment mainly comprises urban travel, which is characterized by frequent, short-distance trips. Other passenger movements include long-distance, surface trips (by road or rail) and air travel, which has been expanding steadily for several years. Passenger travel is measured in passenger-kilometers.

60%: The increase in CO2 emissions from the transportation sector expected by 2050 in the absence of mitigation measures. 

According to the International Transport Forum (ITF)1, a specialized intergovernmental organization within the Organisation for Economic Co-operation and Development (organization for economic co-operation and development (oecd)Founded in 1960, the OECD promotes policies that will improve the economic and social well-being of people around the world...), both freight and passenger volumes will see strong growth to 2050, with freight transportation demand projected to triple from 110,000 billion to around 330,000 billion tonne-kilometers and passenger transportation demand expected to more than double from 50,000 billion to over 120,000 billion passenger-kilometers. The number of motor vehicles on the road is forecast to rise from 1 billion in 2015 to 2.5 billion in 2050.

CO2 Emissions

The expansion of the global transportation sector poses a challenge in terms of co2See Carbon Dioxid emissions, since most modes of transportation rely on oil-based fuels (transportation accounts for 65% of world oil consumption). For the time being, the use of electricityForm of energy resulting from the movement of charged particles (electrons) through a conductor... as a transportation fuelFuel is any solid, liquid or gaseous substance or material that can be combined with an oxidant... is virtually limited to trains. Nearly a quarter of world CO2 emissions from fuel combustion are produced by the transportation sector.

  • Freight is responsible for 40% of total transportation emissions. About a third of this amount comes from maritime transportation, whose growth is perfectly illustrated by the boom in mega container ships, while two-thirds is attributable to road and rail traffic. Road traffic has been growing swiftly as the economic epicenter shifts to emerging markets in Asia and Africa, where rail infrastructure is lacking.
  • Of the 60% of transportation emissions relating to passenger traffic, nearly half is generated by urban travel. Consequently, urban mobility policies are set to play a key role in the fight against global warmingGlobal warming, also called planetary warming or climate change....
  • Air travel (international and domestic) accounts for just 16% of passenger transportation emissions, and sea traffic makes an insignificant contribution. This means that land-based passenger travel (urban and non-urban) is the prime source of emissions.
  • In France, the transportation sector as a whole (passenger and freight) is the largest contributor (28.9%) to greenhouse gas (ghg) Gas with physical properties that cause the Earth's atmosphere to warm up. There are a number of naturally occurring greenhouse gases... emissions (almost entirely CO2). Its share began to grow in 1990 (22%) but stabilized in 20102. Road traffic accounts for more than 95% of emissions.

According to the ITF’s baseline scenario, which is based on current carbon emissions rates and policies in effect today, emissions from global transportation will rise by 60% between 2015 and 2050. Even in the organization’s most optimistic scenario, which assumes that low-carbon technologies will have been deployed, overall emissions in 2050 will only stay at 2015 levels. This would be a remarkable feat since transportation volume is projected to double or triple over the same period, but it would still fall short of the international community’s target in terms of limiting the rise in average global temperatures.

The airline industry accounts for only 10% of global CO2 emissions from the transportation sector.

Low-Carbon Scenario Objectives

  • In the freight and urban mobility sectors, the objective is to reduce emissions in absolute terms. New technological advances in the fields of engine performance, electric motors, gas engines, conventional fuel efficiency and biofuelA fuel produced from plant or animal matter. There are currently two types of biofuel... are expected to cut emissions by two-thirds, but that will not be enough. It will also be necessary to create new user habits and new supply chain models. In terms of freight, this means implementing truck-sharing, route planning and delivery optimization measures. With regard to urban mobility, this means implementing intermodal, car-sharing and traffic management systems based on big data (see Close-Up: “Urban Mobility”). While the number of cars on the road is expected to double by 2050, cities must maintain urban vehicle usage at 2015 levels, according to the ITF.
  • Although responsible for just 10% of total mobility-related emissions, the airline industry has set itself ambitious mitigation goals. The number of passengers is expected to quadruple between 2015 and 2050, yet the industry is planning to curb emissions by 50%. To do so, it intends to reduce aircraft weight per passenger, enhance engine performance and optimize routes. Another avenue for reducing emissions is biokerosene. Currently used only very rarely, biokerosene could eventually meet more than 70% of all jet fuel supply needs. However, a major obstacle could be its cost at a time when airlines are waging fierce fare wars in an attempt to lure passengers. Airlines have also introduced carbon offset programs which, while not reducing aircraft emissions in absolute terms, may help combat climate change by providing support to sustainabilitySustainability indicates a state that is sustainable or reasonably manageable over the long term. projects, such as reforestation3.




(1) ITF Transport Outlook 2017

(2) Transportation statistics in France (in French only)

(3) Les Echos (in French only)