Disentangling Dynamical Controls on Deglacial Hydroclimate in Eastern North America

The scientific objective of this project is to determine the sensitivity of eastern North American hydroclimate to climate forcings and feedbacks during the last deglaciation (~19,000 - 11,000 years before present). By measuring stable isotopes in leaf waxes archived in lake sediments along a latitudinal gradient, the researchers aim to track northward moisture import into eastern North America by the North Atlantic Subtropical High. These measurements will provide constraints on the sensitivity of the North Atlantic Subtropical High and hydroclimate in eastern North America to increases in greenhouse gas concentrations, ice sheet loss, and ocean heat transport variability. Presently, complex land-ocean-atmosphere couplings govern spatial precipitation patterns in eastern North America, making them difficult to disentangle. Pairing new hydroclimate reconstructions with isotope-enabled climate simulations could help unravel the controls on eastern North American hydroclimate during the last deglaciation. The potential Broader Impacts include the potential for greater understanding of changing North American hydroclimate and associated natural hazards, as well as support for early career scientists, post-doctoral scholars, undergraduate students, and ongoing partnership with the Natural Science Explorers Program at Syracuse University. 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.