Transportation and gas emissions
Greenhouse effect

It is now commonplace to say that emissions of greenhouse gases (GHGs) cause, by their accumulation in the atmosphere, a gradual rise in temperatures of a magnitude likely to trigger a real climate change with very serious consequences in many parts of the globe. Considerable and globally coordinated efforts are needed to prevent such a scenario, or at least limit its severity, as agreed by the 196 parties that approved the agreement concluding the COP 21 held in Paris in December 2015. This agreement is only a step. It must now be ratified by a sufficient number of States and translated into effective measures.
Although transport is far from being the only activity contributing to emissions, its share is massive and is therefore necessarily one of the fields where substantial reductions must be achieved. Among the main sectors of activity, the contribution of transport to emissions from European Union countries is 22% (see figure). There is also the French singularity, because of the low emissions of its energy sector. It follows that in proportion the other sectors are more contributors than in the European average, and in particular the transport which accounts for 33% of the emissions in France.

Emission of greenhouse gases (in CO2 equivalent)
in Europe and France (2012) –
Breakdown by economic sector (%)
Greenhouse gas emissions, average by country, in Europe (t / y / capita, 2012)

The importance of transport is all the greater as it is the only activity that increases its emissions despite efforts, some of which have been launched for a long time already, to reduce them: the progress here is more difficult and therefore require special attention and solutions – technical, organizational, regulatory, policy, behavioral solutions, etc. – more innovative or more radical than in other areas.

Evolution of GHG emissions by sector

Finally, transport emissions are distributed very unequally between modes of transport. Given its leading role on the European continent, the road is the source of 72% of emissions. This is also due to its own energy efficiency, lower than that of the railway, the waterway or shipping for the transport of cargo in large quantities. In political terms, we find here the traditional question of « modal shift » (of the road to alternative modes), which we note the low achievement or failure to date. As a result, the bulk of the GHG reductions due to transportation must be within the highway itself, capable of considerable progress, without neglecting the alternatives offered by other transport technologies and their intermodal combinations.

Share of the different modes in the emissions of
transport in Europe (%)

The comparison of diagnoses and solutions sought in different European countries shows great diversity. Scientific and technical research, as well as forecasting and planning, are very uneven. In some cases, public policies aim to influence the behavior of transport users (passengers, freight forwarders), improve the supply of services and renew the equipment used for better energy and environmental efficiency. In others, transport policy is explicitly linked to an industrial policy, so that the national economy can produce as quickly as possible new materials that meet the need to reduce transport GHG emissions.
These concerns are obviously present at the community level. In 2010, the Commission’s Communication « Europe 2020: A strategy for smart, sustainable and inclusive growth » 1 aimed, by 2020, for a 20% reduction in GHGs compared with 1990, the scope of the renewable energy in all energy at 20% and finally an improvement in energy efficiency of 20%. These objectives are being achieved, despite the increase in transportation emissions.
In July 2016, the Commission published: « A European Strategy for Low Emissions Mobility » 2. As a follow-up to « Europe 2020 », this communication deepens transportation issues in overall GHG reduction efforts. The French viewpoints (with the « Low Carbon National Strategy: SNBC » of January 20153 and the « Strategy for the Development of Clean Mobility » of June 20164) converge with these orientations, which we hope will be implemented effectively.
Michel Savy
Professor Emeritus at the University of Paris Est
(Paris School of Urban Planning, Ecole des Ponts-ParisTech) Director of OPSTE