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This review paper examines the greenhouse gas (GHG) emission reduction targets postulated by a range of organizations seeking to reduce the consequences of global climate change and how, or if, the global tourism sector can achieve its share of those targets. It takes both existing estimates of current tourism GHG emissions and emissions projected in a business-as-usual scenario through to 2035 and contrasts them with the "aspirational" emission reduction targets proclaimed by the sector. Analysis reveals that with current high-growth emission trends in tourism, the sector could become a major global source of GHGs in the future if other economic sectors achieve significant emission reductions. Success in achieving emission reductions in tourism is found to be largely dependent on major policy and practice changes in air travel, and stated tourism emission reduction targets do not appear feasible without volumetric changes considering the limited technical emission reduction potential currently projected for the aviation sector. The opportunities and challenges associated with a shift towards a low-carbon global economy are anticipated to transform tourism globally and in all respects. Much greater consideration and dissemination of these issues is required to inform future tourism development and travel decisions.
In order to gain a more mature share in the future energy supply, green gas supply chains face some interesting challenges. In this thesis green gas supply chains, based on codigestion of cow manure and maize, are considered. The produced biogas is upgraded to natural gas quality and injected into the existing distribution gas grid and thus replacing natural gas. Literature research showed that relatively much attention has been paid up to now to elements of such supply chains. Research into digestion technology, agricultural aspects of (energy) crops and logistics of biomass are examples of this. This knowledge is indispensable, but how this knowledge should be combined to help understand how future green gas systems may look like, remains a white spot in the current knowledge. This thesis is an effort to fill this gap. A practical but sound way of modeling green gassupply chains was developed, taking costs and sustainability criteria into account. The way such supply chains can deal with season dependent gas demand was also investigated. This research was further expanded into a geographical model to simulate several degrees of natural gas replacement by green gas. Finally, ways to optimize green gas supply chains in terms of energy efficiency and greenhouse gas reduction were explored.
Energy efficiency, greenhouse gas reduction and cost price of a green gas supply chain were evaluated. This supply chain is based on co-digestion of dairy cattle manure and maize, biogas upgrading and injection into a distribution gas grid. A defined reference scenario reflects the current state of practice, assuming that input energy is from fossil origin. Possible improvements of this reference scenario were investigated. For this analysis two new definitions for energy input-output ratio were introduced; one based on input of primary energy from all origin, and one related to energy from fossil origin only. Switching from fossil to green electricity significantly improves the energy efficiency (both definitions) and greenhouse gas reduction. Preventing methane leakage during digestion and upgrading, and re-using heat within the supply chain show smaller improvements on these parameters as well as on cost price. A greenhouse gas reduction of more than 80 % is possible with current technology. To meet this high sustainability level, multiple improvement options will have to be implemented in the green gas supply chain. This will result in a modest decrease of the green gas cost price.
PBL is the initiator of the Work Programme Monitoring and Management Circular Economy 2019-2023, a collaboration between CBS, CML, CPB, RIVM, TNO, UU. Holidays and mobility are part of the consumption domains that PBL researches, and this project aims to calculate the environmental gains per person per year of the various circular behavioural options for both holiday behaviour and daily mobility. For both behaviours, a range of typical (default) trips are defined and for each several circular option explored for CO2 emissions, Global warming potential and land use. The holiday part is supplied by the Centre for Sustainability, Tourism and Transport (CSTT) of the BUas Academy of Tourism (AfT). The mobility part is carried out by the Urban Intelligence professorship of the Academy for Built Environment and Logistics (ABEL).The research question is “what is the environmental impact of various circular (behavioural) options around 1) holidays and 2) passenger mobility?” The consumer perspective is demarcated as follows:For holidays, transportation and accommodation are included, but not food, attractions visited and holiday activitiesFor mobility, it concerns only the circular options of passenger transport and private means of transport (i.e. freight transport, business travel and commuting are excluded). Not only some typical trips will be evaluated, but also the possession of a car and its alternatives.For the calculations, we make use of public databases, our own models and the EAP (Environmental Analysis Program) model developed by the University of Groningen. BUAs projectmembers: Centre for Sustainability, Tourism and Transport (AT), Urban Intelligence (ABEL).
In the Glasgow declaration (2021), the tourism sector promised to reduce its CO2 emissions by 50% and reduce them to zero by 2050. The urgency is felt in the sector, and small steps are made at company level, but there is a lack of insight and overview of effective measures at global level.This study focuses on the development of a necessary mix of actions and interventions that the tourism sector can undertake to achieve the goal of a 50% reduction in greenhouse gases by 2030 towards zero emissions by 2050. The study contributes to a better understanding of the paths that the tourism sector can take to achieve this and their implications for the sector. The aim of the report is to spark discussion, ideas and, above all, action.The study provides a tool that positively engages the sector in the near and more distant future, inspires discussion, generates ideas, and drives action. In addition, there will be a guide that shows the big picture and where the responsibilities lie for the reduction targets. Finally, the researchers come up with recommendations for policymakers, companies, and lobbyists at an international and European level.In part 1 of the study, desk research is used to lay the foundation for the study. Here, the contribution of tourism to global greenhouse gas emissions is mapped out, as well as the image and reputation of the sector on climate change. In addition, this section describes which initiatives in terms of, among other things, coalitions and declarations have already been taken on a global scale to form a united front against climate change.In part 2, 40 policies and measures to reduce greenhouse gas emissions in the sector are evaluated in a simulation. For this simulation, the GTTMdyn simulation model, developed by Paul Peeters from BUAS, is used which works on a global scale and shows the effect of measures on emissions, tourism, transport, economy, and behaviour. In this simulation, the researchers can 'test' measures and learn from mistakes. In the end one or more scenarios will; be developed that reach the goals of 50% reduction in 2030 and zero emissions in 2050. In part 3, the various actions that should lead to the reduction targets are tested against the impacts on the consequences for the global tourism economy, its role in providing leisure and business opportunities and the consequences for certain destinations and groups of industry stakeholders. This part will be concluded with two workshops with industry experts to reflect on the results of the simulation.Part 4 reports the results of the study including an outline of the consequences of possibly not achieving the goal. With this, the researchers want to send a warning signal to stakeholders who may be resistant to participating in the transition.
Client: Blue Plan regional activity centre (UNEP/MAP), subcontracted through TEC Conseille, Marseille As part of a regional workshop organized by the Blue Plan in July 2008, one of the conclusions of the Group "Tourism and Climate Change” was the need for saving energy in tourism transportation and particularly of air transport, as air transport is responsible for the largest share of greenhouse gas emissions caused by tourism. In the period 1998-2005, the share of international arrivals by air in the Mediterranean area rose from 23% to 40%, respectively, or in numbers, from 47 to 122 million tourists. Some countries, particularly islands, almost entirely depend on air transport for their international tourism. For example in 2005 air transport is used by 87%, 78%, 73%, 64% and 51% of international tourists arriving in, respectively, Israel, Egypt, Spain, Tunisia and Morocco. According to Plan Bleu forecasts on international arrivals, assuming that the share of air transport remains the same, the number of tourists travelling by plane will reach over 158 million by 2025. Given the role of aviation in the emissions of greenhouse gases (GHG), such a development is clearly not sustainable in the light of the necessary reduction of emissions to avoid dangerous climate change. The overall aim of the study is to inform policy makers and entrepreneurs in both destination and in origin countries, on possible options to reduce emissions of greenhouse gases from air travel, while at the same time not impairing the economic development of tourism. To do this, CSTT has developed a tourism scenario model for all countries with Mediterranean coasts describing inbound and outbound international tourism and domestic tourism by all available transport modes and giving both contributions to GDP and total GHG emissions. This model responses to global mitigation policies (increasing the cost of carbon emissions) as well as national policies (taxes, subsidies and changes in transport quality per transport mode). Using the model both global and national policies can be assessed as well as the risks of global mitigation policies for specific countries.