Engineering Commons^™

Mapping Michigan's Historic Coastlines, Ryan A. Williams

Dissertations, Master's Theses and Master's Reports

This five-year project, sponsored by the Michigan Department of Environment, Great Lakes, and Energy, is working to map how Michigan’s Great Lakes shorelines have changed over the past 80+ years. Products of this project include publicly available digital, georeferenced, historic aerial photography datasets, as well as map layers depicting the locations of historic shorelines and bluff lines from 1938, 1980, 2009, 2016, 2018, and 2020. Additional products include bluff retreat risk areas, shoreline rate of change map layers, and tools to assist in the development of future Coastal Vulnerability Index projects for the Great Lakes. All products are available as …

A Model To Predict Concentrations And Uncertainty For Mercury Species In Lakes, Ashley Hendricks

Dissertations, Master's Theses and Master's Reports

To increase understanding of mercury cycling, a seasonal mass balance model was developed to predict mercury concentrations in lakes and fish. Results indicate that seasonality in mercury cycling is significant and is important for a northern latitude lake. Models, when validated, have the potential to be used as an alternative to measurements; models are relatively inexpensive and are not as time intensive. Previously published mercury models have neglected to perform a thorough validation. Model validation allows for regulators to be able to make more informed, confident decisions when using models in water quality management. It is critical to quantify uncertainty; …

Evaluation, Improvement, And Application Of Models Of Environmental Fate And Transport Of Atmosphere-Surface Exchangeable Pollutants (Aseps), Tanvir Khan

Dissertations, Master's Theses and Master's Reports

Certain toxic, semivolatile chemicals, also known as atmosphere-surface exchangeable pollutants (ASEPs) are emitted into the environment from anthropogenic activities and natural sources. This dissertation focused on the (i) evaluation and improvement of dry particle deposition and atmosphere-surface exchange parameterizations of ASEPs for use in chemical transport models (CTMs), and (ii) application of a dynamic multimedia model to examine recovery of Lake Superior from historical inputs of polychlorinated biphenyl (PCB) compounds (a class of ASEPs) contamination.

Current knowledge has been inadequate to propose quantitative measures of the relative performance of available dry particle deposition parameterizations. In Chapter 1 of this dissertation, …