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Climate Impact On Groundwater Flow Processes In The Cedar Creek Watershed And Cedarburg Bog, Jackson Graham

Theses and Dissertations

A local-scale groundwater-flow model of the Cedar Creek Watershed and Cedarburg Bog area was constructed to determine the effects of future changes in temperature and precipitation on water resources. The Cedar Creek Watershed is a 330 km2 sub-basin of the Milwaukee River Watershed located about 30 km north of Milwaukee. The importance of this watershed lies in its location at the sub-continental divide separating the Mississippi River Basin from the Great Lakes Basin. The coupled steady-state and transient flow models incorporate interaction between surface water features and groundwater-surface water interactions. The 4 layer model simulates the influence of recharge on …

Assessing The Impacts Of Climate Change, Urbanization, And Filter Strips On Water Quality Using Swat, Mike Psaris, Heejun Chang

International Journal of Geospatial and Environmental Research

Precipitation changes and urban growth are two factors altering the state of water quality. Changes in precipitation will alter the amount and timing of flows, and the corresponding sediment and nutrient dynamics. Meanwhile, densification associated with urban growth will create more impervious surfaces which will alter sediment and nutrient loadings. Land and water managers rely on models to develop possible future scenarios and devise management responses to these projected changes. We use the Soil and Water Assessment Tool (SWAT) to assess potential changes in stream flow, sediment, and nutrient loads in two urbanizing watersheds in Northwest Oregon, USA. We evaluate …

Impacts Of Spatial, Environmental, And Compositional Differences On Community-Level Flowering Phenology, Isaac William Park

Theses and Dissertations

This dissertation investigates three important topics related to flowering phenology throughout the United States. First, this work evaluates the utility of herbarium records for estimating historical variation in community-level flowering phenology, and evaluate the relationship of such estimates to satellite-derived greenup timing at regional scales. This dissertation then reconstructs historical variations in flowering phenology throughout the spring, summer, and autumn across South Carolina for the years 1951 through 2009. These estimates will then be compared to seasonal temperature variations throughout this period. Finally, this dissertation develops novel herbarium-based methods to separate intraspecific phenological variations over space from changes in flowering …

Understanding The Electricity-Water-Climate Change Nexus Using A Stochastic Optimization Approach, Ivan Saavedra Antolinez

Theses and Dissertations

Climate change has been shown to cause droughts (among other

catastrophic weather events) and it is shown to be exacerbated by the

increasing levels of greenhouse gas emissions on our planet. In May 2013, CO₂ daily average concentration over the Pacific Ocean at Mauna Loa Observatory reached a dangerous milestone of 400 ppm, which has not been experienced in thousands of years in the earth's climate. These levels were attributed to the ever-increasing human activity over the last 5-6 decades. Electric power generators are documented by the U.S. Department of Energy to be the largest users of ground and …

Re-Examining An Air Mass-Based Approach To Detecting Structural Climate Change, 1948-2011, Joseph James Larsen

Theses and Dissertations

Air mass-based approaches to observing changes in climate can have considerable value beyond simple trends of temperature and moisture, providing more thorough understanding of structural climate patterns. Few methodologies have adequately characterized recent air mass modification, however. This research seeks to update and improve upon the methods of a prior study, providing new data from 1948-2011, as well as more rigorous statistical analyses. Air mass types were created, and monthly averages of temperature, dewpoint, and relative frequency were calculated for each of the air masses in all four seasons; then the time series were submitted to regression analysis. The results …

Decadal Changes And Future Projections Of Precipitation In The Metropolitan Area Of Milwaukee, Anke Petra Maria Keuser

Theses and Dissertations

This research investigated decadal changes and future projections of precipitation in the Metro Milwaukee and surrounding area, the largest urban area in Wisconsin. Spatial and temporal precipitation patterns derived for the Metro Milwaukee from the high-resolution gridded historical climatic dataset for Wisconsin were analyzed for 1950-2006. In addition, precipitation scenarios were generated via statistical downscaling of the Third Generation Coupled Global Climate Model (CGCM3) outputs. The delta method was chosen for the statistical downscaling of the CGCM3 output for the two future time periods, 2041-2070 (2050s) and 2071-2100 (2080s). The Mann-Kendall test and the Sen's slope test were applied to …