Collaborative Research: The Drivers of Regionally Coherent Meridional Variability Across the Australian and Asian Monsoons Over the Common Era

The Eastern Hemisphere tropics and subtropics are highly sensitive to variations in regional monsoon precipitation, which provides the majority of freshwater for the ~40% of the world population who reside there. Understanding interannual to multidecadal variations in the monsoon is critical for managing water resources. This project will compile data from cave deposits, corals and tree rings, as well as develop new records from caves in the Philippines and northern Australia, to produce a reconstruction of the behavior of the Austral-Asian monsoon for the last 1000 years. This reconstruction will guide a set of climate model simulations to identify the drivers of monsoon variability. The results will improve decadal prediction the Austral-Asian monsoon. The project will support the participation of a postdoc and undergraduate students in the research, an art-science collaboration, K-12 education, and public outreach to primary and secondary students in Iowa, California, New Mexico and Northern Australia. The goal of this project is to synthesize existing data from stalagmites, corals and tree rings with new cave records from the Philippines and northern Australia to reconstruct the Austral-Asian monsoon for the last 1000 years. The resulting multi-proxy reconstruction will guide a suite of climate model simulations, including large ensembles and isotope-enabled models, to identify drivers of monsoon variability and quantify the relative contributions of external (solar, aerosol, greenhouse gas) and internal (tropical basin interactions) forcings. The results will improve decadal prediction the Austral-Asian monsoon. The project will support the participation of a postdoc and undergraduate students in the research, an art-science collaboration, K-12 education, and public outreach to primary and secondary students in Iowa, California, New Mexico and Northern Australia. This award reflects NSF's statutory mission and has been deemed worthy of support through evaluation using the Foundation's intellectual merit and broader impacts review criteria.