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Environmental Engineering Commons

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Full-Text Articles in Environmental Engineering

The Seasonal Effects Of Photovoltaic Cells On Sedum Eco Roof Substrate Moisture, Brook M. Thompson Oct 2020

The Seasonal Effects Of Photovoltaic Cells On Sedum Eco Roof Substrate Moisture, Brook M. Thompson

University Honors Theses

This paper investigates a combined PV eco roof system and analyzes the soil moisture levels in front of the panels and directly underneath the PV Cells on an experimental ecoroof platform in Portland, Oregon. The purpose of the study was to examine how PV Cells create differences in the moisture level of the soil on the ecoroof. Four moisture sensors were set in different quadrants in four experimental testbeds, and the moisture level data was recorded from October 18th, 2018 to September 10th, 2019. The study found that in with heavy rainfall, the front of the …


Sea Level, Tidal, And River Flow Trends In The Lower Columbia River Estuary, 1853-Present, Stefan Talke, Andrew Mahedy, David A. Jay, Patrick Lau, Conrad Hilley, Amanda Hudson Feb 2020

Sea Level, Tidal, And River Flow Trends In The Lower Columbia River Estuary, 1853-Present, Stefan Talke, Andrew Mahedy, David A. Jay, Patrick Lau, Conrad Hilley, Amanda Hudson

Civil and Environmental Engineering Faculty Publications and Presentations

Few tidal records are available pre-1900 for the Pacific Ocean. We improve data coverage by recovering historical tabulations and digitizing analog tide rolls from Astoria, Oregon for 1853-1876. Nearly 13,500 overlapping images of tides from 1855-1870 were digitized at a 6 minute resolution using a line-finding algorithm. Available hourly and high/low tabulations were also digitized, as were nearby hourly records from 1933-1943. Uncertainty was assessed by evaluating manual staff measurements, historical documents, and leveling surveys. Results suggest that uncertainty in mean sea level varies from ± 0.07m (early 1850s) to ± 0.03m (1867-1876) and is driven primarily by datum and …