Developing an impact-based combined drought index for monitoring crop yield anomalies in the Upper Blue Nile Basin, Ethiopia

Content: 1. Introduction 1.1 Background 1.2 Drought monitoring 1.3 Problem statement 1.4 Research objectives 1.5 Main steps in research methodology1.6 Research significance and innovation 1.7 Description of the study area 1.8 Dissertation structure 2. Spatio-temporal assessment of meteorological drought under the influence of varying record length 2.1 Introduction 2.2 Stations selection and data analysis 2.3 Selection of the Probability Distribution Function (PDF) for the Standardized Precipitation Index (SPI)2.4 Methodology of experiments 2.5 Results and discussion 2.6 Conclusion 3. Comparison of the performance of six drought indices in assessing and characterising historic drought events 3.1 Introduction 3.2 Data 3.3 Drought indicators 3.4 Methods3.5 Results and discussion 3.6 Conclusion 4. Developing a combined drought index and prediction model to monitor drought-related crop yield reduction 4.1 Introduction 4.2 Data 4.3 Methods4.4 Results and discussion 4.5 Conclusions 5. Application of Earth observation data for developing a combined drought index and crop yield prediction model 5.1 Introduction 5.2 Data 5.3 Methods5.4 Results and discussion 5.5 Prediction models of crop yield anomalies 5.6 Conclusions 6. Summary, conclusions and recommendations 6.1 Summary 6.2 Conclusions 6.3 Recommendations References Appendix A: Gamma distribution based SPI calculation Appendix B: Time series of drought indices Appendix C: Spider web plots of drought indicator results for selected stations Appendix D: Scatter plots of drought indices versus crop yield anomalies Appendix E: The regression equations developed for the selected eight zones and for the four crops