The Indian Ocean is unique among the other tropical ocean basins due to the seasonal reversal of monsoon winds and concurrent ocean currents, lack of steady easterlies that result in a relatively deep thermocline along the equator, low-latitude connection to the neighboring Pacific and a lack of northward heat export due to the Asian continent. These characteristics shape the Indian Ocean’s air-sea interactions, as well as its variability on (intra)seasonal, interannual, and decadal timescales. They also make the basin and its surrounding regions, which are home to a third of the global population, particularly vulnerable to anthropogenic climate change: robust trends in heat transport and freshwater fluxes have been observed in recent decades in the Indian Ocean and Maritime Continent region. Advances have recently been made in our understanding of the Indian Ocean’s circulation, interactions with adjacent ocean basins, and its role in regional and global climate. Nonetheless, significant gaps remain in understanding, observing, modeling, and predicting Indian Ocean variability and change across a range of timescales.

This session invites contributions based on observations, modelling, theory, and palaeo proxy reconstructions in the Indian Ocean that focus on understanding recent observed and projected changes in Indian Ocean physical and biogeochemical properties and their impacts on ecological processes, links between Indian Ocean variability and monsoon systems on (intra)seasonal to interannual timescales, interactions and exchanges between the Indian Ocean and other ocean basins, natural decadal variability, and extreme events. Contributions are sought in particular that address research on the Indian Ocean grand challenges highlighted in the recent IndOOS Decadal Review, and as formulated by the Climate and Ocean: Variability, Predictability, and Change (CLIVAR), the Sustained Indian Ocean Biogeochemistry and Ecosystem Research (SIBER), and the International Indian Ocean Expedition 2 (IIOE-2) programs.