ACDI Seminar Series: Water Resources Modelling to support an assessment of the economic impacts of climate change in South Africa
ACDI ADAPTATION SEMINAR SERIES
Join us for a lunch-time, weekly seminar series where we will hear from and engage with various academics and practitioners working in the climate change adaptation space.
Where: Environmental and Geographical Sciences, Studio 5, Upper Campus, University of Cape Town.
When: Wednesday, 12 March 2014 from 13h00-14h00.
“WATER RESOURCES MODELLING TO SUPPORT AN ASSESSMENT OF THE ECONOMIC IMPACTS OF CLIMATE CHANGE IN SOUTH AFRICA” James Cullis
The objective of this study was to investigate the potential impacts of climate change on the economy of South Africa using an integrated modelling framework of impacts through the water supply and infrastructure channels. Hybrid frequency distributions (HFD) of all possible climate futures were obtained from the output of all General Circulation Models (GCMs). Over 6000 possible climate futures were thinned to 367 for an Unconstrained Emissions (UCE) and a Level 1 stabilisation (L1S) scenario. These scenarios were used as the inputs to a rainfall-runoff and irrigation demand model resulting in frequency distributions of possible impacts on catchment run-off, irrigation demands and dryland crop yields for South African. A national scale water resources yield model was developed and used to assess the possible impacts of these changes on the water supply to urban, bulk industry, hydropower, and irrigation sectors. In general the GCMs show drying in the east of the country and wetting in the west. On the whole irrigation demands are likely to increase with increasing evaporative demand, except where these are off-set by increasing precipitation. As a result of the priority of urban and industrial supply, the greatest impact in areas of reducing yield will be felt in the agricultural sector. The use of HFDs rather than individual model outputs provides managers with a sense of the potential risk of extreme scenarios resulting from climate change. The results of this study show that while adopting a L1S scenario does not results in major changes in the median value of expected impacts by 2050, there is a reduction in the risk associated with extreme scenarios at both ends of the spectrum. The results also show the potential for the well developed and integrated water supply system in South Africa to mitigate potential climate change impacts, resulting in reduced economic impacts through the water sector..
Dr. James Cullis is a water resources engineer specialising in water resources planning and management in Africa. He is currently an associate in the water resources group at Aurecon, based in Cape Town, South Africa. After graduating with a BSc. In civil engineering from the University of Cape Town James spent three years as a Rhodes Scholar at Oxford University in the UK. During this period he obtained a second degree in Politics, Philosophy and Economics and an MSc. in Environmental Change and Management. His MSc. thesis looked at the concept of water poverty mapping. James returned to South Africa and started work as an engineer in the water resources group of Ninham Shand consulting engineers. He worked on a number of projects including engineering design, water resources studies, and the development of water related policy for the Department of Water Affairs. After five years, James moved with his family to the USA to complete his PhD at the University of Colorado. His research focused on eco-hydraulics and in particular the interaction between river dynamics and the growth and removal of benthic algae in high gradient streams. During this time James spent six weeks in the McMurdo dry valleys of Antarctica. In 2011, James returned to South Africa as an associate at Aurecon. He is currently involved in a number of water related projects in Africa including feasibility studies, water resources planning, and the evaluation of climate change impacts and the potential for adaptation and sustainable development. James is a registered professional engineer and is married with three children living in Cape Town, South Africa.
*Bring your lunch along, refreshments will be provided