RAPID: Transfer of critical analytical capabilities to measure the isotopic and elemental composition of air in ice cores

About This Grant

Ice cores provide detailed records of Earth’s recent geologic past, with the oldest records currently extending back in time six million years. Critically, ice cores preserve a direct sample of the atmosphere, allowing scientists to reconstruct its past composition. From such measurements we now understand past natural changes in greenhouse gas concentrations and their relationship to the ice age cycles. Ice core measurements of the major atmospheric gases (nitrogen, oxygen, argon) and their isotopic composition provide important information about past global photosynthesis, past conditions at the ice core site, and they can help determine the age of the ice samples. The US research community has lost the capability to perform these measurements over the last year due to retirements and recent instrument failure. The objective of the project is to retain these critical analytical capabilities for the US ice core community and to train the next generation researchers in their use. The work supports a graduate student, contributing to development of the STEM (science, technology, engineering and mathematics) workforce. The project centers around knowledge transfer from scientists at Scripps Institution of Oceanography (SIO), where these techniques were perfected, to scientists at Oregon State University (OSU). OSU has a dual-inlet isotope-ratio mass spectrometer with the correct cup configuration for the analysis, but no experience with the sample preparation and calibration. The project supports: travel between SIO and OSU for knowledge transfer focused on the sample preparation and analytical techniques; method development at OSU to implement the experience that was developed at SIO over the last decades; training of a graduate student at OSU to perform the measurements; and a measurement campaign to analyze ice core samples from two East Antarctic ice cores. The ice cores to be analyzed are the European-drilled Dronning Maud Land ice core, for the purpose of calibrating the ice core “water isotope thermometer”, and from a US-drilled core from Dome C to help constrain long-term changes to the galactic cosmic ray flux. The analytical capabilities retained under this proposal are critical to the success of several ongoing and future US ice coring projects. This award reflects NSF's statutory mission and has been deemed worthy of support through evaluation using the Foundation's intellectual merit and broader impacts review criteria.