Busan Atmosphere Cryosphere Ocean Conference BACO-25: Our Interconnected Earth

The IUGG Associations for Atmosphere, Oceans and Cryosphere - IAMAS, IAPSO and IACS - held a Joint Scientific Assembly in Busan, South Korea, from 20 to 25 July 2025. This was the first joint assembly of all three associations since 2009, when they met in Montreal, Canada. It was the first time any of the associations had been hosted in Korea. And it had been two decades since any of them had met in Asia. Busan was a great choice!The Local Organizing Committee, chaired by Prof. Kyung-Ja Ha of Pusan National University, oversaw the successful organization of the event. The assembly brought together 1,725 participants in total, including 1,282 researchers and 443 invited participants and individuals involved in side events, exhibitions, media coverage, and volunteer work. Participants came from 46 countries across Asia, Europe, North America, South America, Africa, and Oceania. IAMAS had 736 participants, IAPSO 321, and IACS 225. Survey data from 951 respondents revealed that Early Career Scientists, defined as those within 10 years of receiving their PhD, accounted for approximately 25% of participants. The demographic profile skewed young, with 66% of attendees in their 20s and 30s.The scientific program was organized by Prof. Seon-Ki Park (Chair), the Secretaries General from all three Associations, and the Local Organizing Committee. Reflecting the theme "Our Interconnected Earth," the scientific program emphasized integrated approaches to climate systems, addressing climate change and environmental challenges through collaborative, transdisciplinary research.