Physical Sciences and Mathematics Commons^™

Permafrost, Ice Sheets, And Sea Level, Beth Caissie, Julie Brigham-Grette

IPY STEM Polar Connections

Sea level rise and inhabited coastlines. Ice shelves and sea ice do not contribute to sea level but they can buttress the land ice sheets from rapid retreat. Causes of Sea Level Rise:

•Melting of glaciers, ice caps, ice sheets •Thermal expansion of sea water ••Small scale changes due to anthropogenic land water storage (damming rivers, over-pumping of water and fuels, wetland and forest destruction) •Relative changes in sea level due to tectonic movements (land subsidence or rebound)

A New Technique For Firn Grain-Size Measurement Using Sem Image Analysis, N.E. Spaulding, D.A. Meese, I. Baker, P.A. Mayewski

Dartmouth Scholarship

Firn microstructure is accurately characterized using images obtained from scanning electron microscopy (SEM). Visibly etched grain boundaries within images are used to create a skeleton outline of the microstructure. A pixel-counting utility is applied to the outline to determine grain area. Firn grain sizes calculated using the technique described here are compared to those calculated using the techniques of Gow (1969) and Gay and Weiss (1999) on samples of the same material, and are found to be substantially smaller. The differences in grain size between the techniques are attributed to sampling deficiencies (e.g. the inclusion of pore filler in the …

Climate Investigations Using Ice Sheet And Mass Balance Models With Emphasis On North American Glaciation, Sean David Birkel

Electronic Theses and Dissertations

This dissertation describes the application of the University of Maine Ice Sheet Model (UM-ISM) and Environmental Change Model (UM-ECM) to understanding mechanisms of ice-sheet/climate integration during ice ages. The UM-ECM, written by the author for this research, calculates equilibrium biome and snow/ice mass balance solutions for the globe based on modern input climatology and user-defined parameter values. The program was produced in conjunction with a National Science Foundation ITEST grant meant to seed inquiry-based classroom study of Earth systems using computer models. To that end, the UM-ECM serves as both a research and teaching tool. The model has a web-based …