My work has largely focused on the following question: how did landscapes respond to climate variability during glacial-interglacial cycles? I’ve used lake sediment cores to address this question, invoking multiple physical, geochemical, and biological analyses. This builds a history of environmental change within the lake basin, and can help determine whether or not the site was sensitive to global climate events. Below are descriptions and resources on multi-proxy projects I’ve completed in North American regions.
The Last Glacial in subalpine Southern California
My Ph.D. research at UCLA Geography was based on analyzing multiple proxies from a ~125,000-year old core from the San Bernardino Mountains. Baldwin Lake is a sensitive site in a mediterrean-desert ecotone, and analyses showed high amplitude changes in lake level, moisture availability, erosion, wildfire, and forest structure. I proposed that summer insolation and North Atlantic warming were likely climatic drivers in Southern California’s mountains prior to the Last Glacial Maximum. This interpretation was based upon physical and geochemical results published in Quaternary Science Reviews this year. Pollen, charcoal, and stable isotope results are forthcoming.
Some resources for the ~27 m Baldwin Lake core:
Glover et al. (2017) QSR data supplement [.xls file]
BDL12 sed/strat short summary [.pdf]
BDL12 photos and descriptions [.zip file]
Timing of Midwest Deglaciation
I had my start in lake coring and analysis while pursuing my M.S. at the University of Cincinnati. Radiocarbon ages from a series of small-basin cores throughout Ohio and Indiana showed that landscape exposure (and therefore deglaciation) occurred rapidly, within 2-3,000 years of the ice sheet’s maximum extent.
Glover et al. (2011) Ohio-Indiana radiocarbon data [.csv file]
includes a few corrections since publication
My animation of Ohio-Indiana deglaciation, visualizing retreat of the ice margin (based on Dyke, 2004) and exposure of these small basins: