ABSTRACT
This study evaluates the effect on the availability of water resources for agriculture of expected future changes in precipitation and temperature distributions in north-western Africa. It also puts forward some locally derived adaptation strategies to climate change that can have a positive impact on water resources in the Chtouka Aït Baha region. Historical baselines of precipitation and temperature were derived using satellite data respectively from CHIRPS and CRU, while future projections of temperature and precipitation were extracted from the Coordinated Regional Climate Downscaling Experiment database (CORDEX). Projections were also generated for two future periods (2030-2049 and 2080-2099) under two Representative Concentration Pathways: RCP4.5 and RCP8.5. Regional climate models and satellite data outputs were evaluated by calculating their bias and RMSE against historical baseline and observed data. Under the RCP8.5 scenario, temperature in the region shows an increase by 2°C for the 2030-2049 time period, and by 4 to 5°C towards the end of the 21st century. According to the RCP4.5 scenario, precipitation shows a reduction of 10 to 30% for the period 2030-2049, up to 60% for 2080-2099. Outputs from the climate change projections were used to force the HEC-HMS hydrological model. Simulation results indicate that water deficit at basin level will likely triple towards 2050 due to increase in water demand and decrease in aquifer recharge and dam storage. This alarming situation, in a country that already suffers from water insecurity, emphasizes the need for more efforts to implement climate change adaptation measures. This paper presents an assessment of 38 climate change adaptation measures according to several criteria. The evaluation shows that measures affecting the management of water resources have the highest benefit-to-efforts ratio, which indicates that decision makers and stakeholders should increasingly focus their efforts on management measures.
ABSTRACT
BACKGROUND: Reducing the potential for large scale loss of life, large numbers of casualties, and widespread displacement of populations that can result from natural disasters is a difficult challenge for the individuals, communities and governments that need to respond to such events. While it is extremely difficult, if not impossible, to predict the occurrence of most natural hazards; it is possible to take action before emergency events happen to plan for their occurrence when possible and to mitigate their potential effects. In this context, an Atlas of Disaster Risk is under development for the 21 Member States that constitute the World Health Organization's (WHO) Eastern Mediterranean (EM) Region and the West Bank and Gaza Strip territory. METHODS AND RESULTS: This paper describes the Geographic Information System (GIS) based methods that have been used in order to create the first volume of the Atlas which looks at the spatial distribution of 5 natural hazards (flood, landslide, wind speed, heat and seismic hazard). It also presents the results obtained through the application of these methods on a set of countries part of the EM Region before illustrating how this type of information can be aggregated for decision making. DISCUSSION AND CONCLUSION: The methods presented in this paper aim at providing a new set of tools for GIS practitioners to refine their analytical capabilities when examining natural hazards, and at the same time allowing users to create more specific and meaningful local analyses. The maps resulting from the application of these methods provides decision makers with information to strengthen their disaster management capacity. It also represents the basis for the reflection that needs to take place regarding populations' vulnerability towards natural hazards from a health perspective.
