The Indian Ocean received a lot of attention before the 1980s, due to its very dynamic seasonal variability in response to reversing monsoon winds. At the turn of the millennium, the discovery of the Indian Ocean Dipole and new work on the Madden-Julian Oscillation underscored the basin's importance for global climate. This invigorated efforts to improve observing systems in that basin, which has, in turn, stimulated a renewed interest in characterising and understanding biogeochemical and ecological variability. As a result, significant advances have been made in our understanding of the Indian Ocean's circulation, interactions with adjacent ocean basins, biogeochemistry and ecology, and the role of the basin in regional and global climate. Nonetheless, significant gaps remain in the observing system and our understanding. With one third of the world population living in countries around the Indian Ocean, it is also very important to better understand its response to anthropogenic climate change. This session invites contributions that address Indian Ocean variability and change across a range of timescales, based on observations, modelling, and theory. In particular, research that focuses on interactions between physical, biogeochemical, and ecological processes in the Indian Ocean and links between the Indian Ocean and other oceanic basins is encouraged. Contributions are also sought that address research on the grand challenges in the Indian Ocean system, as formulated by the Oceans and climate: variability, predictability, and change (CLIVAR), the Sustained Indian Ocean Biogeochemistry and Ecosystem Research (SIBER), and the International Indian Ocean Expedition 2 (IIOE-2) programs.

This session is dedicated to honour the late Gary Meyers. His contributions have been instrumental in advancing Indian Ocean research. Gary Meyers played a pivotal role in establishing sustained ocean observing systems in the Indian Ocean, and he made major contributions to understanding the circulation in the Indo-Pacific, including the Indonesian Throughflow, the role of the Indian Ocean for regional climate variability and change, and facilitating interdisciplinary research.

Invited speaker: Ming Feng (CSIRO, Australia)