Application of the urban airshed model in the Lower Fraser Valley, British Columbia
department or school: Science, Faculty of
department or school: Earth, Ocean and Atmospheric Sciences, Department of
data provider: DSpace
degree campus: UBCV
creator: Suzuki, Natalie M.
issued: 2009-03-24T23:03:13Z
issued: 1997
related degree: Master of Science - MSc
degree grantor: University of British Columbia
description: The Lower Fraser Valley (LFV) of outhwestern British Columbia is periodically subject to unacceptably high concentrations of ground-level ozone (O₃). To investigate the factors which influence elevated 0₃ concentrations in the LFV, a three-dimensional Eulerian model called the Urban Airshed Model was used to simulate an historical O₃episode which occurred between July 17-19, 1985. The results showed generally satisfactory model performance for predicted O₃ levels across the region, relative to model performance parameters established elsewhere. Peak unpaired accuracies ranged from -2% to -24% and normalized gross error ranged from 35.6-36.9% over the three-day simulation. However, there was a tendency for the model to underestimate O₃concentrations, as reflected in the normalized bias, which ranged from -29.1 to -31.3%. Spatial patterns of predicted O₃concentrations indicated that higher O₃concentrations were observed along the valley walls and tributary valleys than on the valley floor where most of the population resides. Overall model performance based on nitrogen dioxide levels was within established parameters, although concentrations were typically underestimated and performance at two stations was poor. As a further means of assessing model performance, 0three indicator species (NOy, 0₃/NOz and H₂O₂/HNO₃) were calculated to determine the ozone sensitivity of the modelled airshed. The findings suggest that with the exception of sites located far downwind of the major source region, conditions tended to be VOC-limited.
aggregated CHO: https://circle.library.ubc.ca/rest/handle/2429/6440
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note: A P P L I C A T I O N OF T H E U R B A N A I R S H E D M O D E L IN T H E L O W E R F R A S E R V A L L E Y , BRITISH C O L U M B I A By Natalie M . Suzuki B. A.Sc. (Chem. Eng.) University of British Columbia, 1983 Dipl. Meteorology University of British Columbia, 1991 A THESIS S U B M I T T E D IN P A R T I A L F U L F I L L M E N T O F T H E R E Q U I R E M E N T S F O R T H E D E G R E E O F M A S T E R O F S C I E N C E in T H E F A C U L T Y O F G R A D U A T E STUDIES A T M O S P H E R I C S C I E N C E We accept this thesis as conforming to the required standard T H E U N I V E R S I T Y O F BRITISH C O L U M B I A August .1997 © Natalie M . Suzuki, 1997 In presenting this thesis in partial fulfilment of the requirements for an advanced degree at the University of British Columbia, I agree that the Library shall make it freely available for reference and study. I further agree that permission for extensive copying of this thesis for scholarly purposes may be granted by the head of my department or by his or her representatives. It is understood that copying or publication of this thesis for financial gain shall not be allowed without my written permission. Atmospheric Science The University of British Columbia 2075 Wesbrook Place Vancouver, Canada V6T 1W5 Date: 9? /v?/zc Abstract The Lower Fraser Valley (LFV) of southwestern British Columbia is periodically subject to unacceptably high concentrations of ground-level ozone (O3) . To investigate the factors which influence elevated 0 3 concentrations in the L F V , a three-dimensional Eulerian model called the Urban Airshed Model was used to simulate an historical O 3 episode which occurred between July 17-19, 1985. The results showed generally satis-factory model performance for predicted O 3 levels across the region, relative to model performance parameters established elsewhere. Peak unpaired accuracies ranged from -2% to -24% and normalized gross error ranged from 35.6-36.9% over the three-day simu-lation. …
has type: Thesis/Dissertation
date issued: 1997-11
is shown at: 10.14288/1.0052636
language: eng
degree discipline: Atmospheric Science
provider: Vancouver : University of British Columbia Library
publisher: University of British Columbia
rights: For non-commercial purposes only, such as research, private study and education. Additional conditions apply, see Terms of Use https://open.library.ubc.ca/terms_of_use.
scholar level: Graduate
type: Text
identifier URI: http://hdl.handle.net/2429/6440