The Carbon Cost of Travel to a Medical Conference: Modelling the Annual Meeting of the Canadian Association of Gastroenterology.

Objectives: We estimated and compared the travel related carbon emissions of the annual meeting of the Canadian Association of Gastroenterology between the two most common geographical locations of the meeting. Methods: We modelled the car, train and flight travel journey of each registrant to two annual meetings. One was held in Toronto, close to where the majority of Gastroenterogists live, the other in Banff in the west of the country. We used validated carbon emission outputs per kilometer of travel. Results: The average per capita distance travelled to the Toronto meeting was 2845 km, resulting in 0.540 tonnes (t) of CO2equivalent (CO2e) emitted per person. When the meeting was held in Banff emissions were 41% higher than those in Toronto with an average distance travelled of 3949 km and 0.760t of CO2e emitted per person. Almost all of the travel related carbon emissions for both meetings were generated by flying. Conclusions: Even when held close to the largest population centre, there is a large environmental impact from travel to annual meetings. Importantly, choice of meeting location has a very big impact on difference in carbon emissions. Societies need to consider the site of meetings and reduce the number of in-person attendees if they wish to reduce their carbon footprint. Hybrid models participants should be considered. Our analysis also suggests, other medical societies who wish to model their annual meetings can use a simplified model, using flying distance only, to estimate travel-related emissions.