Increasing demand on the accuracy of 5-day forecast to subseasonal to seasonal (S2S) and climate prediction requires advanced research on coupled modeling between the atmosphere, ocean, land, sea ice, and hydrology. Initialization of these models is an important aspect of forecasting in the coupled system. This session solicits contributions on impacts of new data types on coupled process modeling, impacts of initialization across the coupled interface, coupled data assimilation, and other aspects of initialization in the coupled modeling framework. Submissions representing all spatial scales (i.e., global, regional, mesoscale) are encouraged.