Research interests:

1. My research uses the tools of isotope geochemistry to reconstruct past climates with a focus on the hydrological history of the world’s drylands. My current projects include:
   

2. •Developing records of past water balance changes in the U.S. Great Basin using precisely dated cave and lake deposits
   

3. •Reconstructing changes in North African dust emissions associated with the beginning and end of the African Humid Period
   

4. •Refining our reconstruction and interpretation of past dust flux changes
   

5. My work primarily involves measurements of uranium and thorium isotopes, which are used for dating in terrestrial carbonates and for estimating dust accumulation rates in marine sediments. Additionally, I use helium isotopes in dust studies and oxygen and carbon isotopes and trace element concentrations in cave deposits.
   

Images: MODIS image of March 2, 2003 Saharan dust plume from http://earthobservatory.nasa.gov; A view from the top of Wheeler Peak (Nevada) on the western edge of the Bonneville Basin (photo by Jay Quade).