Modelling the Impacts of Climate Change on the Hydrodynamics and Biogeochemistry of Lake Simcoe, Hamilton Harbour and the Bay of Quinte
Loading...
Authors
Bolkhari, Hadiseh
Date
2014-10-03
Type
thesis
Language
eng
Keyword
DYRESM-CAEDYM , ELCOM-CAEDYM , Climate Change , Algal Blooms , Cyanobacteria
Alternative Title
Abstract
This thesis focuses on 3 Ontario water bodies (Hamilton Harbour, the Bay of Quinte and Lake Simcoe), which are vital for economic and recreational activities, yet are threatened by eutrophication, which leads to low dissolved oxygen concentrations (hypoxia) and harmful algae blooms. Among them, Hamilton Harbour and Bay of Quinte are listed as Great Lakes Areas of Concerns (AOCs). To develop effective Remedial Action Plans (RAPs) the potential impacts of climate change on the water quality problems must be assessed. The main objective of this study is to predict the effects of future climate change on the water quality and the implications for lake restoration through computational modeling. A vertical one-dimensional (1D) computational model, Dynamic Reservoir Simulation Model (DYRESM) coupled to Computational Aquatic Ecosystem Dynamics Model (CAEDYM) was applied to Lake Simcoe and Hamilton Harbour. We forecasted the response of the Lake to two greenhouse gas GCM emissions scenarios (A2 and B1). There is a relatively small difference between A2 and B1 predictions. According to the simulations, Lake Simcoe will be stratified 4.5 days per decade longer until 2100 and the length of hypoxia will increase from 55 days to ~100 days. Hamilton Harbor, will be stratified approximately 6 days per decade longer by 2100 and the hypoxic period is projected to increase from 150 days to 200 days. In Lake Simcoe, the mean surface cyanobacteria biomass during the stratified season is simulated to increase from ~ 0.2 ugL-1 to ~1 ug L-1 by 2066 as a consequence of a warming climate.
The three-dimensional (3D) hydrodynamic Estuary and Lake Computer Model (ELCOM) combined with CAEDYM was applied to Bay of Quinte. The model results were comprehensively validated against the observed physical (temperature), chemical (nutrients) and biological (phytoplankton biomass) parameters. The model was then forced for the periods of 2000-2004 and 2066-2070, with North American Regional Climate Change Assessment Program (NARCCAP) meteorological data. The simulations show an increase in surface temperature of 2-3.5C with minimal simulated effects on cyanobacteria. The average May-October TP concentrations in present and future simulations are higher than the RAP target (~0.1 mg L-1), from loads to the upper Bay, and biomass is consistently below the RAP target range (<4 ug L-1) in the
iii
middle and lower sections of the Bay and above the target (10-15 ug L-1) in the upper reaches during 2000 to 2004. In future simulations, the average phytoplankton biomass will increase to (6-8 ug L-1), being mostly high in the upper Bay (14-15 ug l-1). If predicted changes in surface water temperatures are realized under climate change, the phosphorus concentrations of inputs to the Bay would need to be decreased by ~50%, compared to present values, to maintain recommended RAP phytoplankton concentrations
Description
Thesis (Ph.D, Civil Engineering) -- Queen's University, 2014-10-03 09:59:17.652
Citation
Publisher
License
This publication is made available by the authority of the copyright owner solely for the purpose of private study and research and may not be copied or reproduced except as permitted by the copyright laws without written authority from the copyright owner.