Location matters! Optimizing venue selection and attendance format to lower the carbon footprint of air travel to the Australasian College of Dermatologists ASM

The COVID-19 pandemic prompted reconsideration of how conferences are delivered, leading to a shift from in-person gatherings to virtual formats. Post-pandemic, many conferences have adopted a hybrid model, allowing in-person attendance and the option to participate via conference call or web interface, synchronously or asynchronously. Australia's vast landmass and relatively low population density means the distance between major cities is typically larger than in other countries,1 making air travel the most common modality for conference travel.2 We sought to measure the carbon footprint associated with simulated attendance in different host cities at the Australasian College of Dermatologists Annual Scientific Meeting. Our goals were to measure the emissions of an in-person gathering, compared to a hybrid attendance model, and to compare emissions by changing the venue location to optimize and reduce carbon emissions. Air-travel emissions and travel distances were sourced from the International Civil Aviation Organization.3 Dermatologist numbers and locations were provided by the Australasian College of Dermatologists.4 Virtual attendance emissions were calculated based on the most carbon-intensive scenario: high-definition video conferencing for the entire conference.5 Complete data and analyses are available as an Appendix S1. The carbon footprint for complete in-person attendance was highest in Darwin (318,726 kgCO2e), followed by Perth (278,305 kgCO2e), while Sydney had the lowest carbon footprint (97,673 kgCO2e) (Table 1). Using Sydney as a baseline, relocating the event to Melbourne, Brisbane, or Canberra resulted in an increase of less than 50% in kgCO2e, with Adelaide being slightly higher at 54%. Switching to a fully virtual conference reduces emissions by more than 99% due to the minimal environmental impact. For Perth and Darwin to match Sydney's carbon emissions, 65% of Perth's delegates and 70% of Darwin's delegates would need to attend virtually. Figure 1 presents a weighted analysis of carbon emissions and the impact of different host cities. Being the most remote and therefore requiring the highest number of dermatologists to travel via air (n = 710), Darwin resulted in the largest carbon emissions per delegate. Despite ranking fourth in the number of dermatologists needing air travel (n = 655), Perth had the second-highest carbon emissions due to the long distance. In contrast, Hobart and Canberra, with the second-largest number of dermatologists travelling by air (n = 706), had lower emissions—ranked third and sixth, respectively—due to shorter travel distances. The central finding of this study is the host city's location impacts carbon emissions significantly; the host city determines the number of dermatologists travelling by air, and the distance travelled. These emissions can be significantly reduced by optimizing the selection of host city locations. The secondary finding of this study is through the adoption of a hybrid model; emissions can be further reduced. This study has several limitations. It does not provide a full lifecycle analysis, which means it omits the energy consumption involved in operating the conference venue, including, temperature control, lighting, audio-visual equipment, catering, accommodation, ground transportation, as well as the additional energy demands from virtual attendance, such as printing educational materials and sending follow-up emails. Although lifecycle analyses would offer a more comprehensive assessment, previous studies have shown that air travel is the largest contributor to the carbon footprint of conferences.6 To address this issue, the British Association of Dermatologists, European Academy of Dermatology & Venereology, American Academy of Dermatologists and the World Congress of Dermatology - which includes all global colleges - are providing options for virtual participation. Additionally, this analysis made assumptions of all delegates travelling by air, using the most efficient flight paths, economy class travel, and does not account for the attendance of delegates' families. In-person meetings offer many benefits, such as networking, mentoring and socializing, which may be diminished in virtual settings. Engaging in discussions or asking questions can also be more challenging online than in face-to-face interactions. Additionally, delegates may experience fatigue from extended use of online platforms, commonly referred to as ‘Zoom fatigue’.7 Despite these challenges, a recent survey of scientists revealed that 74% of respondents prefer scientific meetings to be held virtually.8 Incorporating a virtual component into conferences could enhance participation and promote equity, especially for attendees from low- and middle-income countries who face systemic challenges in traveling to global health events.9 It would also benefit those with family obligations, such as childcare, or other logistical barriers.10 Currently, there are no high-quality studies comparing data retention or social networking outcomes between in-person and virtual conferences but a recent survey demonstrated that most dermatologists are willing to adopt virtual conferences. We recommend that the educational outcomes of all types of online learning are studied closely and we remain responsive to research and recommendations in this area. The factors above are all important to consider when planning a conference and the carbon footprint should be one of the considerations as well. The carbon footprint of our Annual Scientific Meeting is substantial but modifiable. By carefully considering the choice of host city, the number of delegates flying and integrating a virtual component (hybrid model), conference organizers can optimize these parameters to ensure strong attendance, while minimizing the environmental impact. None. HPS is a shareholder of MoleMap NZ Limited and e-derm consult GmbH and undertakes regular teledermatological reporting for both companies. HPS is a Medical Consultant for Canfield Scientific Inc. and a Medical Advisor for First Derm. He is also an Editorial Board member of the Australasian Journal of Dermatology and a co-author of this article. To minimize bias, he was excluded from all editorial decision-making related to the acceptance of this article for publication. The data underlying this article are available in the article and in its Appendix S1. Appendix S1 Please note: The publisher is not responsible for the content or functionality of any supporting information supplied by the authors. Any queries (other than missing content) should be directed to the corresponding author for the article.