Collaborative Research: Orbital forcing of Andean Hydroclimate from the legacy drill cores of Lake Titicaca

About This Grant

Sustainability of water supplies in the Andes Region in South America is put at risk by a warming climate, which is causing glacier retreat and contributing to the decline of lakes and reservoirs. This research project will analyze sediment cores from Lake Titicaca—the highest navigable freshwater lake in the world—and use these data to help uncover how natural Earth system processes have influenced water supply, glacier coverage, and ecosystems in the high Andes over the past 370,000 years. The findings will help explain when and why major droughts occurred in the past—and what these events can reveal about future water-related risks. Findings will be shared through a bilingual website, public presentations and outreach. All data and models will be freely available to researchers, policy makers, and local partners. By linking ancient climate events with present-day challenges, this work will help regional planners and communities understand and address future risks to water resources. This research project will develop a new record of precipitation, isotopes, temperature, and lake level spanning the past ~370,000 years using legacy drill cores from Lake Titicaca. The project will use these data to explore how the surrounding environment has changed, with a focus on understanding long-term water resource availability in the Andes. The analysis of geochemical and isotopic signals preserved in the sediments will be used to reconstruct how the regional environment responded to environmental shifts over glacial–interglacial timescales. To deepen understanding of these changes, the sediment-based environmental reconstructions will be paired with computer model simulations and AI-assisted methods for refining large-scale data to the local level. New time-slice experiments with isotope-enabled climate models spanning the last glacial cycle will help to better understand the drivers of environmental changes, including the relative roles of local and remote forcings on the South American Monsoon System, and will be a resource for future research by the paleoclimate community. This award is co-funded by the Division of Earth Sciences (EAR) and the Division of Atmospheric and Geospace Sciences (AGS). 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.