From the Preface: The purpose of this document is to motivate and coordinate U.S. participation in the Second
International Indian Ocean Expedition (IIOE-2) by outlining a core set of research priorities that
will accelerate our understanding of geologic, oceanic, and atmospheric processes and their
interactions in the Indian Ocean. These research priorities have been developed by the U.S.
IIOE-2 Steering Committee based on the outcomes of an interdisciplinary Indian Ocean science
workshop held at the Scripps Institution of Oceanography on September 11-13, 2017. The
workshop was attended by 70 scientists with expertise spanning climate, atmospheric sciences,
and multiple sub-disciplines of oceanography. Workshop participants were largely drawn from
U.S. academic institutions and government agencies, with a few experts invited from India,
China, and France to provide a broader perspective on international programs and activities and
opportunities for collaboration. These research priorities also build upon the previously
developed International IIOE-2 Science Plan and Implementation Strategy. Outcomes from the
workshop are condensed into five scientific themes: Upwelling, inter-ocean exchanges,
monsoon dynamics, inter-basin contrasts, marine geology and the deep ocean. Each theme is
identified with priority questions that the U.S. research community would like to address and the
measurements that need to be made in the Indian Ocean to address them.