Diagnosing the relative contributions of glacier retreat and climatic variability to streamflow trends in Illecillewaet catchment
department or school: Arts, Faculty of
department or school: Geography, Department of
data provider: DSpace
degree campus: UBCV
creator: Chai, Zijie
issued: 2023-09-01T20:06:12Z
issued: 2023
related degree: Master of Science - MSc
degree grantor: University of British Columbia
description: Glaciers make significant contributions to streamflow in western North America. However, glaciers throughout the region are losing mass and retreating, leading to concerns about summer streamflow, particularly during extended spells of warm, dry weather. An empirical analysis of climatic and streamflow trends in the Canadian portion of the Columbia River basin found a regional climate-driven decline in August streamflow, which was augmented in glacier-fed catchments by glacier retreat. The objective of this study was to use a hydrological model to quantify the relative roles of glacier retreat and climatic trends on streamflow in Illecillewaet catchment. We applied a modified version of HBV-EC within the Raven modelling framework to Illecillewaet River, located in the Columbia River headwaters, from 1977 to 2020. The model was calibrated using daily streamflow, snow water equivalent from snow pillows and geodetic glacier mass change. The model was run for 1977-2020 with four scenarios: (a) declining glacier cover based on historical imagery; (b) constant glacier extent with 1985 glacier cover; (c) constant glacier extent with 2016 glacier cover and (d) no glacier cover. Key conclusions are: (1) in the Illecillewaet catchment, where glacier cover represents about 5% of the total area, glacier ice melt can contribute between 3.5% and 41.1% to the August streamflow; (2) the analysis of glacier ice melt trends showed a small but statistically insignificant increase, attributed to the synchronous rising of the snowline along with the retreat of the glacier terminus; and (3) the decline in August streamflow appears to have been primarily driven by climate influences, particularly decreasing precipitation in August. Currently, the presence of glaciers helps offset this declining trend, but the glacier compensation effect is weakening as the glaciers retreat.
aggregated CHO: https://circle.library.ubc.ca/rest/handle/2429/85780
note: Diagnosing the relative contributions of glacier retreat andclimatic variability to streamflow trends in IllecillewaetcatchmentbyZijie ChaiB.Sc., Hohai University, 2020A THESIS SUBMITTED IN PARTIAL FULFILLMENT OF THEREQUIREMENTS FOR THE DEGREE OFMASTER OF SCIENCEinTHE FACULTY OF GRADUATE AND POSTDOCTORAL STUDIES(Geography)THE UNIVERSITY OF BRITISH COLUMBIA(Vancouver)August 2023© Zijie Chai, 2023The following individuals certify that they have read, and recommend to the Faculty ofGraduate and Postdoctoral Studies for acceptance, the thesis entitled:Diagnosing the relative contributions of glacier retreat and climatic variability tostreamflow trends in Illecillewaet catchmentsubmitted by Zijie Chai in partial fulfillment of the requirements forthe degree of Master of Sciencein GeographyExamining Committee:Robert Daniel Moore, Professor, Geography, UBCSupervisorGeorg Jost, Adjunct Professor, Geography, UBCSupervisory Committee MemberBrett Eaton, Professor, Geography, UBCAdditional examinerAdditional Supervisory Committee Members:Steven Weijs, Associate Professor, Civil Engineering, UBCSupervisory Committee MemberiiGlaciers make significant contributions to streamflow in western North America. However,glaciers throughout the region are losing mass and retreating, leading to concerns aboutsummer streamflow, particularly during extended spells of warm, dry weather. An empir-ical analysis of climatic and streamflow trends in the Canadian portion of the ColumbiaRiver basin found a regional climate-driven decline in August streamflow, which was aug-mented in glacier-fed catchments by glacier retreat. The objective of this study was to usea hydrological model to quantify the relative roles of glacier retreat and climatic trends onstreamflow in Illecillewaet catchment. We applied a modified version of HBV-EC withinthe Raven modelling framework to Illecillewaet River, located in the Columbia River head-waters, from 1977 to 2020. The model was calibrated using daily streamflow, …
has type: Thesis/Dissertation
date issued: 2023-11
is shown at: 10.14288/1.0435724
language: eng
degree discipline: Geography
provider: Vancouver : University of British Columbia Library
publisher: University of British Columbia
rights: Attribution-NonCommercial-NoDerivatives 4.0 International
rights URI: http://creativecommons.org/licenses/by-nc-nd/4.0/
scholar level: Graduate
contributor: Moore, R. Daniel
type: Text
identifier URI: http://hdl.handle.net/2429/85780