Pratigya Polissar

Research projects are focussed on the causes, and the temperature, rainfall, and ecosystem response to, warm periods in Earth history with emphasis on the past twenty million years. This research includes reconstructing the concentration of atmospheric CO2 in the past using geochemical and isotopic measurements, and determining changes in rainfall patterns and ecosystems from molecular biomarker distributions and isotopic compositions. Projects use lake and ocean sediments and involve organic geochemical and compound -specific isotopic measurements of organic biomarker molecules. These observations from past warm periods are used to test theory and models of climate sensitivity and climate change.