Acquisition of an Analytical Facility for High-Resolution Paleoclimatology

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This award will help enable the acquisition of a suite of laboratory instruments at the University of Arizona (UA) to develop high-resolution records of climate variability on seasonal to multi-decadal time scales. The new instruments will help build analytical capacity at UA to facilitate the development of new cross-disciplinary linkages and collaborative research efforts in paleoclimatology. They will support the activities of a diverse group of researchers working in the Laboratory for Tree Ring Research (LTRR), the Department of Geosciences, the Institute for the Study of Planet Earth (ISPE), the NSF-Arizona Accelerator Mass Spectrometry facility, and several other smaller research groups and individuals in the departments of Physics, Atmospheric Sciences, and Hydrology and Water Resources. The proposed instrumentation includes a continuous flow isotope ratio mass spectrometer (CF -IRMS), a microdensitometer, a scanning micro-x-ray fluorescence spectrometer (scanning micron XRF), a laser particle size analyzer, and an inductively coupled atomic emission spectrometer (ICP-AES). The first two instruments will provide new resources to the Laboratory of Tree-Ring Research that will enable researchers to map latewood density, a proxy for summer temperatures, at an unprecedented 5-micron resolution and with rapid throughput. This will enable the development of centuries-long tree-ring based climate records even in species exhibiting extremely narrow bands. The CF-IRMS is a versatile instrument that will, among other applications, provide an automated high throughput system for measuring stable isotopes in 50-100 gram samples of tree cellulose, permitting reconstruction of past patterns of rainfall in tropical trees lacking annual ring structure. The laser particle size analyzer will provide the capability to derive detailed information about sediment transport mechanisms, provenance, and physical and limnological conditions from sediments. This can be used to infer information about atmospheric circulation and the hydrologic budget. The scanning micron XRF instrument gives the researchers the ability to non-destructively derive rapid and detailed elemental compositional information on very fine spatial scales from many different types of paleoclimate archives, including whole sediment cores. Similarly, the ICP-AES will enable the rapid generation of precise elemental records from marine or terrestrial archives such as corals, mollusks, and speleothems.The ability to develop high-resolution records of climate variability facilitated by the instruments funded with this award would help provide a better understanding of the potential effects on human populations of abrupt climate change and of the interactions between human activity and climate. The researchers plan to capitalize on the new facility to create a more integrated paleoclimate research and training program at the University of Arizona. They also plan to design a new course intended to train undergraduate and graduate students in paleoclimate methods and applications - a hands-on course that will not only enable more use of the instrumentation, but also lead to the development of a new methods and applications manual for use by students on campus and beyond.