The reversion to in-person conferences in the environmental sciences post-COVID: Documenting patterns and recommending strategies to reduce carbon footprint and increase accessibility

Scientific conferences play a crucial role in facilitating knowledge exchange, collaboration, and opportunities across the global research community. The COVID-19 pandemic demonstrated that online and hybrid models are feasible at the large scale, with two major advantages: online conferencing substantially reduces carbon emissions, and enhances accessibility for early career researchers and underrepresented groups and countries in science. At the same time, limitations, like the lack of in-person social interactions, became apparent. Aiming to understand the trajectory of conferencing post-pandemic, we documented the format of 23 international conferences focused on environmental science and biodiversity from 2018 to 2024, and surveyed conference managers about future plans. We observed a strong resurgence of in-person events beginning in 2022, comprising 70 % of all conferences in this sample by 2024, alongside a decline in hybrid formats, with 2024 being the first post-pandemic year in which none of the sampled conferences were held fully online. An anonymous sample of 14 conference managers revealed varied future strategies. Some conferences plan to continue hybrid formats, although interest in online participation in such conferences appears to be waning. Others are exploring combining online and in-person components within or across years, separating some conference activities into online events, and prioritizing the engagement of people who cannot travel. Sophisticated multi-hub or social media models may provide an optimal blend of climate-friendly science and networking. We argue that post-pandemic, environmental societies should expand their missions beyond hosting in-person meetings to include public outreach and scientific training — functions particularly well-suited to online platforms. • We rated the conference format of 23 environmental societies from 2018 to 2024. • In addition, an anonymous survey of conference managers yielded 14 responses. • Since 2022 there has been a reversion of in-person events, to 70 % in 2024. • Managers' plans included online elements and in-person events, combined or separate. • The carbon and inclusivity benefits of online conferencing should not be abandoned.