Ice surface reconstruction and energy balance modeling of alpine glaciers Public Deposited

http://ir.library.oregonstate.edu/concern/graduate_thesis_or_dissertations/t435gg85q

Descriptions

Attribute NameValues
Creator
Abstract or Summary
  • Glacial deposits on San Francisco Mountain, Arizona, were mapped in order to provide constraints on ice extents in separate valleys for late Pleistocene glacial events. Qualitative and semi-quantitative relative dating methods were employed in order to correlate moraines between drainages and to provide a basis for distinguishing between separate glacial events within drainages. Morphologic and surficial weathering characteristics that were measured include degree of moraine dissection, moraine crestal width, moraine inner and outer slope angle, surface boulder frequency, percentage of weathered surface boulders, percentage of pitted surface boulders, maximum pit depth, and percentage of split boulders. Results of the relative dating study support past studies that differentiate 3 separate drift sequences on the mountain. Five separate glacier surfaces were reconstructed from the mapped moraine crests, four for the most recent glaciation, and one for the intermediate glacial event. ELAs from the reconstructed glaciers range from 3140 to 3400 meters. In addition, a numerical model was developed that uses an energy balance approach to calculate annual ablation over a glacier surface. The energy balance approach used in the model was designed to allow the model to test sensitivity of former glaciers to changes in temperature or precipitation. Required model inputs include a two-dimensional elevation map of the glacier surface and surrounding topography, as well as climate records that include daily values of air temperature, wind speed, precipitation, atmospheric vapor pressure, incoming shortwave radiation, and incoming longwave radiation. Model outputs include the net specific balance and equilibrium line altitude of the glacier. Model simulations of mass balance are compared with observed data from the 1990 ablation season at Haut Glacier d'Arolla, Valais, Switzerland. Calculated ablation values closely match observed values, thereby supporting the validity of the model. A preliminary model run was also accomplished for the 5 Pleistocene glaciers reconstructed on San Francisco Mountain, Arizona, using output from a regional climate model as input. The model delivers a glacier that is nearly in mass balance for one of the reconstructions.
Resource Type
Date Available
Date Copyright
Date Issued
Degree Level
Degree Name
Degree Field
Degree Grantor
Commencement Year
Advisor
Academic Affiliation
Non-Academic Affiliation
Subject
Rights Statement
Peer Reviewed
Language
Digitization Specifications
  • File scanned at 300 ppi (Monochrome, 24-bit Color) using ScandAll PRO 1.8.1 on a Fi-6770A in PDF format. CVista PdfCompressor 4.0 was used for pdf compression and textual OCR.
Replaces
Additional Information
  • description.provenance : Approved for entry into archive by Patricia Black(patricia.black@oregonstate.edu) on 2012-08-24T20:49:35Z (GMT) No. of bitstreams: 1 PoellotColinDaniel2001.pdf: 3216301 bytes, checksum: 34fa8c646e0a078f4c67cd18b87eb1c5 (MD5)
  • description.provenance : Made available in DSpace on 2012-08-24T20:49:35Z (GMT). No. of bitstreams: 1 PoellotColinDaniel2001.pdf: 3216301 bytes, checksum: 34fa8c646e0a078f4c67cd18b87eb1c5 (MD5) Previous issue date: 2000-06-05
  • description.provenance : Approved for entry into archive by Patricia Black(patricia.black@oregonstate.edu) on 2012-08-24T20:47:14Z (GMT) No. of bitstreams: 1 PoellotColinDaniel2001.pdf: 3216301 bytes, checksum: 34fa8c646e0a078f4c67cd18b87eb1c5 (MD5)
  • description.provenance : Submitted by Kaylee Patterson (kdpscanner@gmail.com) on 2012-08-24T18:24:13Z No. of bitstreams: 1 PoellotColinDaniel2001.pdf: 3216301 bytes, checksum: 34fa8c646e0a078f4c67cd18b87eb1c5 (MD5)

Relationships

In Administrative Set:
Last modified: 08/09/2017

Downloadable Content

Download PDF
Citations:

EndNote | Zotero | Mendeley

Items