an Amsterdam connection via NS International or Thalys. By July 2020, Lufthansa and Deutsche Bahn expanded their offer through Frankfurt Airport to 17 major cities. International conferences Most international professional or academic conference attendants travel by plane, conference travel is often regarded as an employee benefit as costs are supported by employers. By 2003, Access Grid technology had hosted several international conferences. The Tyndall Centre has reported means to change common institutional and professional practices. Flight shame In Sweden the concept of "flight shame" or "flygskam" has been cited as a cause of falling air travel. Swedish rail company SJ AB reports that twice as many Swedish people chose to travel by train instead of by air in summer 2019 compared with the previous year. Swedish airports operator Swedavia reported 4% fewer passengers across its 10 airports in 2019 compared to the previous year: a 9% drop for domestic passengers and 2% for international passengers. The estimates that 3% of the global population take regular flights. Stefan Gössling of the Western Norway Research Institute estimates 1% of the world population emits half of commercial aviation's CO2, while close to 90% does not fly in a given year. In early 2022, the European Investment Bank published the results of its 2021–2022 Climate Survey, showing that 52% of Europeans under 30, 37% of people between 30 and 64 and 25% for people aged 65 and above plan to travel by air for their summer holidays in 2022; and 27% of those under 30, 17% for people aged 30–64 and 12% for people aged 65 and above plan to travel by air to a faraway destination. Personal allowances Climate change mitigation can be backed by Personal carbon allowances (PCAs) where all adults receive "an equal, tradable carbon allowance that reduces over time in line with national targets." Everyone would have a share of allowed carbon emissions and would need to trade further emissions allowances. An alternative would be rationing everyone’s flights: an "individual cap on air travel, that people can trade with each other". See also References External links Institutional Concerns Industry Research Studies Aviation Aviation Aviation