Acquisition of a continuous flow isotope ratio mass analyzer for tropical paleoclimatology

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0929983Evans"This award is funded under the American Recovery and Reinvestment Act of 2009 (Public Law 111-5)." This award will facilitate the purchase of a continuous flow isotope ratio mass spectrometer. Requested is a Thermo Delta V with Conflo-IV interface. This instrument is being requested to increase sample sensitivity (and thereby decrease necessary sample size) and because current departmental instrument resources are fully committed. The instrument will be interfaced with existing peripherals These include a Gasbench-II and PAL-80 autosampler allowing carbonate and water prep, and a Costech High Temperature Generator/Elemental Combustion System (HTG/ECS). The PI will assume overall operation, maintenance and oversight responsibility. A half-time laboratory manager will be hired on grant support to assist with instrument operation, maintenance and training. Students will also play a major role. UMd will contribute funds towards the purchase of this instrument. In addition, the University will renovate space to include an IRMS and wet lab within the Department of Geology. The PI will use this instrument for research in two broad themes, Tropical isotope dendroclimatology, and Coral chronologies of interdecadal ocean/atmosphere climate variability. Under the first theme, the PI intends to better understand seasonality in tropical climate regions through oxygen isotopic compositions in trees lacking annual rings. Oxygen isotopes can be used as a proxy for convective rainfall. The in-house developed system allows high sample throughput and rapid analyses so that very high resolution isotope proxy data can be generated. Preliminary results show good correlation between isotope climate reconstructions and ENSO events. Under the second theme (coral chronologies), enhanced sample processing techniques offer precision comparable to dual-inlet measurements in a continuous flow mode. This allows high-resolution carbon and oxygen isotope measurements from coral samples at a rate of ~120 per day. Multi-decadal proxy measurements can thus be made to better understand past climates (and model current and future ones). While forming the basis of the PI?s analytical laboratory at UMd, this instrument will be the foundation of a climate science curriculum offering broad student training. The laboratory will sponsor high school students and provide analytical possibilities for the senior capstone research program and "Earth, Life and Time" Scholars program. The PI will promote women and minorities in his program (of which he has been very successful in the past). ***