Show simple item record

dc.contributor.advisorLi, Danen_US
dc.contributor.authorEhrenfeucht, Shivanien_US
dc.date.accessioned2019-01-28T19:53:28Z
dc.date.available2019-01-28T19:53:28Z
dc.date.issued2018
dc.identifier.urihttps://hdl.handle.net/2144/33222
dc.description.abstractIce cores are a valuable component with regards to paleoclimate reconstruction due to the ability to use stable water isotopic concentrations in ice as a proxy for paleo-temperature records. It is therefore important to understand the processes and conditions under which isotopic concentrations can be altered after ice has formed. Historically, sublimation has been considered to only have a trivial impact on the isotopic record in glacial ice due to the low diffusivity of solid ice (~10-15 m2 s-1). Recent publications have shown that diffusion of impurities through ice can occur at much faster rates than the diffusivity of solid ice would imply, and have proposed that networks of unfrozen liquid (premelt) between ice grains may expedite the diffusion process. However, the application of this mode of diffusion to isotopic concentrations in ice under non-equilibrium conditions has been largely unexplored. Here I model changes in isotopic concentrations in ice using a two-dimensional diffusion mechanism, which incorporates premelt, coupled with a sublimation flux at the surface. Model results show an increase in δD at the ice surface and in near-surface ice. Concentrations exponentially decrease from the surface value to the initial concentration at depth. These results are consistent with recent experimental results.en_US
dc.language.isoen_US
dc.subjectEnvironmental scienceen_US
dc.subjectDiffusionen_US
dc.subjectGlaciologyen_US
dc.subjectIce coresen_US
dc.subjectStable water isotopic fractionationen_US
dc.subjectSublimationen_US
dc.titleModeling post-depositional changes of delta-D in ice due to sublimationen_US
dc.typeThesis/Dissertationen_US
dc.date.updated2018-12-05T02:01:26Z
etd.degree.nameM.A.en_US
etd.degree.levelmastersen_US
etd.degree.disciplineEarth & Environmenten_US
etd.degree.grantorBoston Universityen_US


This item appears in the following Collection(s)

Show simple item record