| ACE | Action for Climate Empowerment |
| AR4 | IPCC’s Fourth Assessment Report |
| AR5 | IPCC’s Fifth Assessment Report |
| ATAG | Air Transport Action Group |
| CBA | Cost-Benefit-Analysis |
| CCS | Carbon Capture and Storage |
| CCU | Carbon Capture and Utilization |
| CDR | Carbon Dioxide Removal |
| CEO | Chief Executive Officer |
| CH4 | methane |
| CIEL | Centre for International Environmental Law |
| CO2 | carbon dioxide |
| CO2eq | carbon dioxide equivalent |
| CORSIA | Carbon Offsetting and Reduction Scheme for International Aviation |
| DESA | Department of Economic and Social Affairs |
| DRV | Deutscher Reiseverband [German Travel Association] |
| EC | European Commission |
| ECA | Emission Control Areas |
| EEA | European Economic Area |
| EU | European Union |
| EU ETS | European Union Emissions Trading Scheme |
| GAP on ESC | Global Action Program on Education for Sustainable Development |
| GDP | Gross domestic product |
| GHG | Greenhouse gases |
| GMST | Global Mean Surface Temperature |
| Gt | Gigatons [unit] |
| HDI | Human Development Index |
| IAEA | International Atomic Energy Agency |
| IATA | International Air Transport Association |
| ICAO | International Civil Aviation Organization |
| ICS | International Chamber of Shipping |
| IEA | International Energy Agency |
| IMO | International Marine Organization |
| INDCs | Intended Nationally Determined Contributions |
| IPCC | Intergovernmental Panel on Climate Change |
| LDC | Least Developed Countries |
| LEL | Lower Explosive Limit |
| LLDC | Landlocked Developing Countries |
| LOSC | UN Law of the Sea Convention |
| MCC | Mercator Research Institute on Global Commons and Climate Change |
| MEP | Member of the European Parliament |
| MEPC | Marine Environmental Protection Committee |
| micro-CHP | Micro combined heat and power |
| MP | Member of the Parliament |
| MRO | Maintenance, repair and overhaul services |
| MSC | Marine Stewardship Council |
| MW | megawatt [unit] |
| N2O | dinitrogen monoxide |
| NASA | National Aeronautics and Space Administration |
| NAZCA | Non-State Actor Zone for Climate Action |
| NDCs | Nationally Determined Contributions |
| NESS | Necessary element of a sufficient set |
| NGO | Non-governmental organization |
| OECD | Organisation for Economic Co-operation and Development |
| OPEC | Organization of Petroleum Exporting Countries |
| PGC | Principle of Generic Consistency |
| ppm | parts per million [unit] |
| RCP | Representative Concentration Pathway |
| RF | Radiative Forcing |
| RTK | Revenue Ton Kilometres, measuring the share in international transport performances |
| SIDS | Small Island Developing States |
| SR15 | IPCC’s Special Report on 1.5 degrees |
| SUV | Sport Utility Vehicle |
| t | tonne [unit] |
| TED | Technology, Entertainment, Design (e.g. talk or conference) |
| UAE | United Arab Emirates |
| UEL | Upper Explosive Level |
| UK | United Kingdom |
| UN | United Nations |
| UNCTAD | United Nations Conference on Trade and Development |
| UNDP | United Nations Development Program |
| UNEP | United Nations Environment Programme |
| UNESCO | United Nations Educational, Scientific and Cultural Organization |
| UNFCCC | United Nations Framework Convention on Climate Change |
| UNWTO | World Tourism Organization (Specialized Agency of the UN) |
| US | United States |
| VAT | Value added tax |
| vol% | volume percent or percentage by volume [unit] |
| WMO | World Meteorological Organization |
| WWF | World Wide Fund for Nature |