This award supports a project to develop and use a new analytical tool for ice core gas and isotope analyses based on an innovative laser spectroscopic technique. The measurements will be integrated with sample processing techniques that continuously melt vertical sections of ice core, and the ancient air that is normally wasted in such sample processing will be released and analyzed. The proposed work focuses on three climatically relevant measurements for which laser technology has sufficiently advanced that ice core applications are possible. These include the atmospheric concentration and stable isotopic composition of methane (delta 13C and delta D), the carbon monoxide mixing ratio, and the isotopic composition of the ice itself (delta D and delta 18O). The biogeochemical rationale for these choices is that methane mixing ratios are highly correlated with temperature change in the northern hemisphere and used as global stratigraphic markers in ice core studies. The methane isotopic composition is important for understanding sources and sinks of methane and addressing controversies over the stability of the large marine hydrate reservoir. Carbon monoxide, which can be measured simultaneously with methane and its isotopes, is involved in biogeochemical cycles that also control methane mixing ratios. The stable isotopes of water are basic tracers of past temperature in ice core research. The proposed work will bring new cutting-edge technology to polar research, and develop it further. The proposed isotopic methods are particularly important in this regard given that these measurements are difficult with traditional methods, the proposed work has the potential to transform isotopic studies of methane in ice. Measuring gases in air released from ice cores during continuous melting of vertical sections for other chemical measurements will save valuable time and precious ice and will ultimately generate trace atmospheric gas data in real time. The project will support both a postdoctoral researcher and a graduate student and will involve a new faculty member who is bringing significant industry experience to academia. The PIs will participate in recruitment efforts that target minority graduate students and post-docs will participate in a variety of outreach efforts, including news interviews, television documentaries, lab tours, mini-classes for gifted middle school students and a new effort with Oregon Museum of Science and Industry to build a climate exhibit.
