Grant: $376,672 - National Science Foundation - May. 26, 2009
50% voted satisfied - 50% voted not satisfied - 2 vote(s) cast
Award Description: Conventional measurements of the stable isotope ratios of water are the cornerstone of polar ice core research, due to their strong and well-understood relationship with local temperature. An additional parameter, 17O-excess, obtained from the high-precision measurement of both 18O/16O and 17O/16O in ice core H2O provides information highly complementary to these traditional measurements. 17O-excess is independent of temperature but depends strongly on the humidity of the ocean surface where moisture evaporates. It therefore offers great potential as a powerful new tool for evaluating climate conditions in the past. In particular, it provides the opportunity to disentangle the effects of source humidity and temperature, changes during transport, and local site temperature, on ice core water isotope records. To date, a complete ice core 17O-excess profile has been obtained only on one ice core, at Vostok in East Antarctica. We propose to obtain an 17O-excess profile from the WAIS Divide ice core, currently being drilled in West Antarctica. WAIS Divide is appealing for comparison with Vostok because it is located in a very different moisture transport regime, and will be influenced by potentially quite different changes in sea ice and atmospheric circulation. Furthermore, the high snowfall rate at WAIS Divide will allow for seasonal analyses to be conducted, which will provide important new constraints on our theoretical understanding of 17O-excess. We will combine our 17O-excess measurements with the oxygen and hydrogen isotopes analyses already being produced in our laboratory to obtain the best possible measures of both local ice sheet temperature, source temperature, and source humidity through time.
Project Description: This grant supports the development of a sample prepations system for the measurement of the rare isotope "Delta"17O in ice core samples from West Antarctica and eventually for making those measurements. We have designed, ordered parts and largely built (~85%) the sample preparation system. We have also identified and admitted a graduate student who will work on this project.
Jobs Summary: PROFESSOR-Requires outstanding, mature scholarship and research as evaluated in terms of national or international recognition, and evidenced by accomplishments in full range of academic responsibilities. (Total jobs reported: 0)
Project Status: Less Than 50% Completed
This award's data was last updated on May. 26, 2009. Help expand these official descriptions using the wiki below.