Show simple item record

dc.contributor.advisorKingston, Daniel
dc.contributor.advisorCullen, Nicolas
dc.contributor.authorJobst, Andreas Maximilian
dc.date.available2017-05-29T01:42:45Z
dc.date.copyright2017
dc.identifier.citationJobst, A. M. (2017). The potential impacts of climate change on the hydro-climate of the Clutha/Mata-Au catchment (Thesis, Doctor of Philosophy). University of Otago. Retrieved from http://hdl.handle.net/10523/7334en
dc.identifier.urihttp://hdl.handle.net/10523/7334
dc.description.abstractThe water resources of the Clutha/Mata-Au catchment have an important economic value (i.e. hydropower and irrigation) for New Zealand/Aotearoa. Climate change is expected to alter both temperature and precipitation, which will then impact seasonal streamflow and water management. However, up to this point no attempt has been made to model coherently the driving natural processes as well as the major water management components. The aim of this dissertation is to assess the potential impacts of climate change on the hydro-climate of the Clutha catchment. An integral part of this study is the implementation of the fully distributed hydrological model WaSiM, which uses process oriented routines and also contains water management modules. To ensure a robust description of the meteorological drivers, existing techniques (e.g. trivariate thin-plate spline) were combined with novel elements (e.g. multi-layer lapse rate model). As a result, realistic spatial estimates of air temperature and precipitation were generated with a higher accuracy than existing products. An extensive validation of WaSiM revealed a good to very good performance when simulating daily and monthly flow during the historic period (1992-2012) at the key sites of the catchment (outflows of natural lakes and catchment outlet). Two versions of WaSiM, only differing in their snow model, were then forced with eight Regional Climate Model (RCM) simulations, stemming from two emission scenarios and four General Circulation Models (GCMs). The RCM data sets were bias corrected using both linear transformation and quantile mapping, and downscaled to the WaSiM grid (1 km2). The hydrological projections encompass substantial increases in streamflow during winter (+22 to +76% by the 2090s) and a decline in summer for most scenarios (-43 to +2% by the 2090s), with similar changes for hydropower production. The dominant drivers are increasing winter precipitation (+25 to +76% by the 2090s) and substantial decreases in the snow storage (due to temperature increase). Additionally, some of the main sources of uncertainty in hydrological projections were investigated. A quantitative approach identified GCM structure as the dominant uncertainty source followed by emission scenario, bias correction and snow model. It can be concluded that the new baseline meteorological dataset, model framework and ensemble of hydrological projections developed here constitutes the most comprehensive assessment of 21st century climate change impacts in the Clutha catchment to date, and as such also provides a new benchmark for future studies.
dc.format.mimetypeapplication/pdf
dc.language.isoen
dc.publisherUniversity of Otago
dc.rightsAll items in OUR Archive are provided for private study and research purposes and are protected by copyright with all rights reserved unless otherwise indicated.
dc.subjectclimate change
dc.subjecthydrology
dc.subjectdownscaling
dc.subjectinterpolation
dc.subjectNew Zealand
dc.subjecthydrological model
dc.titleThe potential impacts of climate change on the hydro-climate of the Clutha/Mata-Au catchment
dc.typeThesis
dc.date.updated2017-05-29T00:59:28Z
dc.language.rfc3066en
thesis.degree.disciplineGeography
thesis.degree.nameDoctor of Philosophy
thesis.degree.grantorUniversity of Otago
thesis.degree.levelDoctoral
otago.openaccessOpen
 Find in your library

Files in this item

Thumbnail

This item appears in the following Collection(s)

Show simple item record