Research Opportunities in the Cobb Lab

1. How did exposure of the Sunda Shelf during the last glacial maximum affect glacial climate, and the distribution and variability of water isotopes?
   Involves: Simulating climate mean state and variability using coupled climate models forced by glacial boundary conditions; parallel simulations with isotope-equipped models; LGM proxy data-model intercomparisons.
2. What is the geochemical and climatic signature of the Toba super-eruption as recorded in cave stalagmites from Borneo?
   Involves: Ultra-high-resolution analyses of stalagmite calcite oxygen isotopes, carbon isotopes, and elemental abudances across a major excursion in Borneo stalagmite paleoclimate records that coincides with the Toba super-eruption.
3. Has recent climate change caused unprecedented changes in coral skeletal morphology and/or geochemistry?
   Involves: Working with a set of modern coral cores from the Line Islands to search for a consistent coral response to recent strong El Nino events, and comparing these signals to those recorded across strong paleo-El Nino events captured in fossil coral cores; requires close collaboration with coral reef ecologists at Georgia Tech and the Scripps Inst. of Oceanography.
4. How has East African climate evolved over the last glacial cycle?
   Involves: Exploring new and existing collections of East African stalagmite records for climate reconstruction.
5. What role to cave microbes play in determining the morphology and geochemistry of cave stalagmites? Involves: isolating, identifying, and culturing microbes that grow on the surface of cave stalagmites for geochemical studies * requires close collaboration with Georgia Tech geomicrobiologists.