Evaluating Climate-related Risks for Biosphere Reserves in South Africa

Climate Risk Informed Decision Analysis (CRIDA) is a bottom-up approach for climate change impact assessment on water resources at a watershed scale. As a part of UNESCO's "Be Resilient South Africa" project and CRIDA's climate change risk assessment, four biosphere reserves (Kruger-to-Canyons, Vhembe, Marico, and Cape Winelands) in South Africa were selected as pilot projects for this work. This research aims to perform a detailed stress test in the pilot areas to eventually be used for developing adaptation strategies. This work utilizes a Weather-Regime-Based Stochastic Weather Generator adopted in South Africa to identify weather regimes and expand the historical meteorological data to perform the stress test. Using the weather generator, different types and levels of incremental changes were made to the historical data based on the input from local stakeholder engagements. Both historical data and perturbations simulated by the weather generator were used as input for site-specific hydrologic models to evaluate the impact of multiple scenarios on a set of stakeholder-informed hydrological and water systems model performance indicators like fire index and environmental flow. The final contributions of the work will be response surfaces of the performance indicators that will help to support adaptation strategy and water systems policy in the region. Although this work is focused on the four biosphere reserves, the next step is to expand the technique throughout South Africa with the help of training and capacity-building sessions in the near future.