1. Relevance and utility of AIACC PROJECT AF07 for stakeholders and decisionmakers and for informing policy choices George Green Water Research Commission, South Africa Water Research Commission, South Africa

2. Development of Regional Climate Change Scenarios for Sub-Sahara Africa seeks to: (a) extend existing capacity among African scientists with regard to selection and implementation of methodologies for constructing regional climate-change scenarios from GCMs (b) provide a comprehensive scenario base for impact studies in Africa.

3. Project relevance and utility Relevance of objectives Relevance and utility of results and outcomes

4. Relevance of objectives from water resources perspective Plausible, scientifically-founded scenarios of climate change at appropriate scales are essential for meaningful assessments of: –potential impacts of climate change –adequacy/inadequacy of adaptation strategies, some of which may already have been developed to cope with current climate variability, especially when policy-making needs to be informed. Conversely, decision-makers and policy-makers who are uncertain about the reality or extent of projected changes in climate, would avoid thinking and acting beyond the need to cope with current climate variability. Greater confidence in ranges of probable climate changes at scales of national and local interest will, however, engender greater willingness to respond promptly and appropriately, even if the confidence bands are initially fairly broad. Therefore, Project AF07 objectives are of fundamental relevance both for policy-makers as well as for more direct users (including AIACC investigators currently engaged in assessment of impacts, vulnerabilities and adaptation options).

5. Indicator of relevance of objectives - AF07 has served as point of departure for a nationally-focused, multi- disciplinary project on climate change for the RSA water sector. Key questions relate to: Scenario plausibility, closeness to reality, confidence intervals Downscaling limits Climate change-associated climate variability (frequency, magnitude, and duration of extreme events) Likely land-use, hydrological and water yield changes and interactions (scenarios required to provide input to hydrological models sensitive to land use changes) Water-related socio-economic impacts and adaptation (relating to sustainability of water-based livelihoods) Detection and monitoring (signals, impacts, adaptation) Project being undertaken by a team of climatologists, hydrologists and social scientists from four South African universities. Objectives refined at an inception workshop involving major stakeholders, who are encouraged to interact with the project team on a continuous basis.

6. Relevance and utility of current AIACC project Progress reported suggests that Project AF07 is succeeding well in meeting its stated objectives. –There has been a dramatic increase in the capacity of African scientists to get to grips with issues related to the downscaling of climate change scenarios. –Investigators are learning how best to exploit strengths/ avoid weaknesses inherent in the GCM projections to be used for downscaling to regional and even to point scales. –Development of downscaling methods has been accomplished early enough for at least some of the current AIACC impact studies to derive some benefit from these methods.

7. Recommendation for increasing relevance/utility Possibly too late for the current round of AIACC impact studies to benefit fully from the sounder climate change scenarios made possible through AF07 However, the relevance and utility of AF07 could still be enhanced: –Through incorporating firmer climate-change scenarios in follow-on projects, especially where this is necessary for results to gain acceptance as a basis for policy-making. Consider supporting such projects. –In future projects, the generation of appropriate, project-specific, climate-change scenarios should preferably not happen outside the projects, but should rather be done as an integral part of a multi- disciplinary approach.