Transport demand evolution in Europe - factors of change, scenarios and challenges

In the transport sector, where change comes with inertia and investments are made with a long term perspective, decision makers need to consider how the future may look like in the very long term. The work presented in this paper is a scenario analysis focusing on the evolution of transport demand towards 2050, aiming to identify related challenges for European industrial and policy players. It follows up on the work of other recent attempts to study the future of transport from a European perspective, integrating findings from these studies, updating new trends and applying a specific scenario analysis methodology relying also on expert consultation. The diversity of the scenarios created unfolds aspects of the future transport system with rather different outcomes on issues like the volume of transport, travel motives, the prevalent spatial scales of transport and logistics, people’s preferences towards different transport attributes, the relevancy of the State versus the private initiative in transport production, the level of competition, or the relative importance of environment and resource scarcity in setting an agenda for innovation and regulations. Beyond the subsequent challenges and opportunities identified in this work, the scenarios developed may be a useful basis for individual actors of distinct backgrounds to build their own specific futures, supporting them in defining strategies for the future

Airguns: Theory and operation of the marine seismic source

A detailed knowledge of the radiation field of seismic sources is essential to effective source design and source wavefield deconvolution. To understand the principles of airgun theory and operation it is necessary to follow the motion of the air bubble that is produced and released underwater by the airgun. An airgun is a mechanical device that releases a high pressure bubble of air underwater, the expansion of the air bubble generates seismic waves the water that are the source waves of the seismic waves used in reflection seismology. This monograph is about the motion of the bubble of air in the water that creates the seismic pressure wave called the airgun signature. The relevant physical principles for a single bubble are discussed first, then the dynamic behavior of the bubble is derived from the basic equations of fluid mechanics for the ocean and thermodynamics for the air. The surface ghost reflection part of the signature is derived and its behavior explained. Once the dynamics of a single bubble is understood, the behavior of an array of airgun bubbles is easy to understand, the reasons for an array are explained and detailed. The discussion then moves on to practical performance specifications in the field. The different types of airguns are discussed and their mechanical operation explained, this leads to the airgun system, a pneumatic-electrical computer controlled system on board the seismic vessel under the control of the GPS navigation system.Geological Science

GHG Mitigation Strategy in the European Transport Sector

Transport accounts for roughly one quarter of all greenhouse gas emissions (GHG) in Europe. Transport is the only sector that has not reduced its GHG in recent years. To meet the European and global targets to reduce GHG in industrialized countries by 80 to 95% until 2050 compared with 1990 requires that the transport sector is put on a pathway to drastically reduce its emissions. The chapter demonstrates that with a combined R&D and transport policy strategy, reductions of 60 to 70% of GHG until 2050 will be achievable for the European transport sector. The analysis to develop the transport strategy combines an analysis of the innovation system of the transport sector with respect to developing GHG reduction technologies of all modes and a model-based quantitative scenario exercise to assess the transport, economic and environmental impact of the scenarios. We intend to support R&D for biofuels for air transport, and R&D for cross-modal transport