My primary research interest is investigating the role that black carbon plays in current and past climate change. Black carbon is a dark absorptive particle produced by the incomplete combustion of fossil and bio-fuels. In the atmosphere black carbon absorbs energy and causes atmospheric heating, while black carbon deposited on snow and ice causes darkening of the surface, resulting in greater absorption of solar energy, heating of the snow/ice, and accelerated snow and glacier melt. Black carbon is a major contributor to observed climate warming, but remains a large source of uncertainty in analyses of climate change.
My research group works to:
To conduct this research we analyze the chemical composition of snow samples and ice cores retrieved from high elevation mountain glaciers and polar ice sheets, make direct atmospheric measurements, and characterize the optical properties of LAI. Instrumentation in my laboratory includes a Single Particle Soot Photometer (SP2), a Sunset organic-elemental carbon analyzer, a Portable UV-VIS-NIR Spectroradiometer (Spectral Evolution), a Hyperspectral Microscope (Cytoviva); and a Simultaneous Thermogravimetric Analyzer (STA 449 F5 Jupiter). My research space includes an ice core/snow walk in freezer and clean room facilities.
My laboratory now provides black carbon analytical services.
In addition to my black carbon research, I am interested in reconstructing past climate (paleoclimatology) to achieve an understanding of how the Earth’s climate system operates, and documenting recent environmental change related to human activities. By analyzing the chemistry (trace and major elements, stable isotopes, and black carbon) of ice cores, the composition of the atmosphere can be reconstructed. Through my research, I have worked in Antarctica, China (Tibetan Plateau), Nepal, Tajikistan, New Zealand, Switzerland and Washington State.