WaRisCo

I am proud to lead this excellent African-German team of WaRisCo, which in co-design with key stakeholders will build resilience to mega-floods and multi-year droughts in a changing climate.

Dr. Sophie Biskop

WaRisCo brings together state-of-the-art climate and hydrological modelling capabilities from Germany and South Africa, to project the likelihood of two of the biggest climate change risks South Africa may face in a warmer world: a ‘day-zero drought’ in Gauteng, and mega-flooding in KwaZulu-Natal.

Prof. Dr. Francois Engelbrecht

Abstract

Southern Africa is projected to become drastically warmer and likely also drier, but with more extreme rainfall events in the east. WaRisCo will explore two of the biggest risks that climate change poses to South Africa:

1. the risk of a day-zero drought in the Gauteng province – an event with potentially disastrous socio-economic and environmental impacts, and
2. the risk of mega-flooding in the Durban region – such floods may be catastrophic in terms of the number of human lives lost.

WaRisCo will develop a comprehensive hydrological modelling system integrating km-scale regional climate data and explorative land-use scenarios, enabling a step-up in the projection of future drought and flood risk in South Africa. Working with key stakeholders, WaRisCo will work towards anticipatory Disaster Risk Reduction (DRR) and climate change adaptation strategies.

Impact

WaRisCo is the first project to directly explore the probability of occurrence of mega drought and flood disasters in South Africa’s Gauteng and KwaZulu-Natal Provinces. Based on this scientific foundation, the research team will develop adaption options to these risks in co-design with key stakeholders in national and local government. Key national implementation stakeholders are the Department of Water and Sanitation and the National Disaster Management Centre, and at the local level, the City of Johannesburg and the South African Cities Network. A particular focus of the project will be the development of climate-smart DRR plans that cater for events unprecedented in the historical record. WaRisCo will offer wide benefits to several sectors, including industry, agriculture and water.

Focal points of the project

• Integrated hydrological model development
• Generating climate change projections at cloud permitting scale
• Development of explorative land use/ management and cover (LUMCC) scenarios
• Projections and assessment of future hydro-climate hazards
• Co-design & co-development of Disaster Risk Reduction (DRR) and adaptation strategies
• Capacity development

WP 1: Integrated Hydrological Model Development

Lead partners: FSU Jena, SYDRO, ARC

WP 1 will combine hydrological modelling with regional climate projections (WP 2) and explorative LUMCC scenarios (WP 3) to develop i) drought-focused models for the Integrated Vaal River System including water transfers between dams and considering management decisions, and ii) flood-focused models for the flood-prone rivers in the Durban region. Three hydrological modelling platforms will be utilised for process- based simulation at river basin scales, namely JAMS/J2000, TALSIM and PITMAN.

WP 2: Generating Climate Change Projections at Cloud Permitting Scale

Lead partners: Hereon-GERICS, Wits-GCI

WP 2 will generate a new set of climate change projections with a very high temporal and spatial resolution at the km-scale for the case study region. Two Regional Climate Models (RCMs), namely CCAM (Wits- GCI) and REMO-NH (Hereon-GERICS), will be used to generate climate projections at a spatial resolution as fine as 3 km. The novel RCM data will serve as input for the hydrological model system.

WP 3: Development of explorative LUMCC
Scenarios

Lead partners: MLU-Hal, Wits-GCI

WP 3 will model land use/management and cover changes (LUMCC) within the context of impacts on hydrological and local climate parameters through changes in evapotranspiration, percolation, runoff, soil-moisture, and subsequently streamflow. Detailed scenarios of future LUMCC in the Integrated Vaal and KwaZulu- Natal River Systems will be developed by implementing different model types relevant for different scales (local to regional).

WP 4: Projections and Assessment of Future Hydro-Climate Hazards

Lead partners: FSU Jena, SYDRO, Wits-GCI, Hereon-GERICS, ARC, MLU-Hal

WP 4 will project changes in the frequency, duration and intensity of hydro-climate hazards, such as extreme floods and multi-year droughts, for different periods in the future, different levels of global warming and as a function of LUMCC. WP 4 will provide tangible outputs related to flood and drought risks that will be the basis for the disaster risk assessment across various sectors.

WP 5: Co-Design and Co-Development of DRR and Adaptation Strategies

Lead partners: MA, FSU Jena, Hereon-GERICS, SYDRO, Wits-GCI, ARC, MLU-Hal, Implementation partners

The research team will engage with key stakeholders towards the co-design of the research outputs for maximum uptake in DRR plans and long-term adaptation strategies, in both the Gauteng Province and Durban region. Moreover, we will co-develop a user-friendly web-based information system, named ‘Safe-Water’, and a transfer concept to ensure the transferability of this project to other hotspots of interest.  

WP 6: Capacity Development

Lead partners: Wits-GCI, FSU Jena, Hereon-GERICS, SYDRO, MLU-Hal

An important aspect of this project is the accompanying capacity building for young researchers, policy-makers and implementation partners throughout the duration of the project. The German and African partners will jointly support bi-national supervised masters and doctoral degrees through bilateral sandwich programmes offered by DAAD. In addition, the project will provide tailor-made capacity building for policy makers and implementation partners to understand the complexity of hydro-climatic extremes.