Browsing by Author "Amare Bantider"

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    Performance evaluation of multiple regional climate models to simulate rainfall in the Central Rift Valley Lakes Basin of Ethiopia and their selection criteria for the best climate model
    (Springer Nature, 2023-05-08) Sisay Kebede Balcha; Taye Alemayehu Hulluka; Amare Bantider; Adane Abebe Awass
    The historical datasets of five regional climate models (RCMs) available in the Coordinated Regional Downscaling Experiment (CORDEX)–Africa database are evaluated against ground-based observed rainfall in the Central Rift Valley Lakes Basin of Ethiopia. The evaluation is aimed at determining how well the RCMs reproduce monthly, seasonal, and annual cycles of rainfall and quantify the uncertainty between the RCMs in downscaling the same global climate model outputs. Root mean square, bias, and correlation coefficient are used to evaluate the ability of the RCM output. The multicriteria decision method of compromise programming was used to choose the best climate models for the climate condition of the Central Rift Valley Lakes subbasin. The Rossby Center Regional Atmospheric Model (RCA4) has downscaled ten global climate models (GCMs) and reproduces the monthly rainfall with a complex spatial distribution of bias and root mean square errors. The monthly bias varies in the range of − 35.8 to 189%. The summer (wet), spring, winter (dry), and annual rainfall varied within the range of 1.44 to 23.66%, − 7.08 to 20.04%, − 7.35 to 57%, and − 3.11 to 16.5%, respectively. To find the source of uncertainty, the same GCMs but downscaled by different RCMs were analyzed. The test results showed that each RCM differently downscaled the same GCM, and there was no single RCM model that consistently simulated the climate conditions over the stations in the study regions. However, the evaluation finds reasonable model skill in representing the temporal cycles of rainfall and suggests the use of RCMs where climate data is scarce after bias correction.
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    Towards Integrated Urban Flooding Risk Management in Ambo Town and its Watershed, West Shoa Zone, Oromia Regional State, Ethiopia
    (Addis Ababa University, 2021-09-01) Gemechu Shale Ogato; Amare Bantider ; Davide Geneletti ; Ketema Abebe
    A GIS-based spatial planning and land use management is asserted to be a versatile tool in building capacities for flood disaster reduction and preparedness underpinning sustainable urban development.The purpose of the study was to analyze urban flooding hazard and risk and develop integrated urban flooding risk management strategy for Ambo town and its watershed. The study adopted a mixed research approch which combined quantitative and qualitative methods of data collection and analysis. The study confirmed that residing in flood prone area, poverty, lack of alternative livelihoods, and lack of proper drainage channels are the underlying causes of socio-economicvulner ability to urban flooding risk in Ambo town. Unwillingness of people to move away from hazard-prone areas due to the nature of their livelihoods, the high prices of properties, and a lack of awareness of the risk of hazards anticipated were identified as internal barriers to governance of urban flooding risk reduction in the study area. A strong positive association was confirmed between urban households’ perception on structural and non-structural measures practiced in Ambo town and their perception on the effectiveness of the current governance of urban flooding risk reduction. A statistically significant relationship was confirmed between respondents ’access to credit and their education level, total income, and employment status. A statistically significant relationship was confirmed between respondents’ perception on their vulnerability to disease after flooding risk and their demographic and socio-economic characteristics. 63.04% of the watershed is moderate flooding hazard area while 52.9% of Ambo town is moderate flooding hazard area. 20.2% of Huluka watershed is moderate flooding risk area while 21% of Ambo town is high and very high flooding risk area. The IDF curves developed indicate that rainfall intensities increase with increase in return periods for all the seven stations and the Huluka watershed. High rainfall intensities were confirmed to be related toshort durations while low rainfall intensities related to long durations for the same return periods. Bush and shrub land, forest, grassland, and water land use/land cover type declined with68.2%, 59.3%, 32.7%, and 5.1% respectively between 1979 and 2017. Based on the land use/ land cover analyisis in the watershed, urban built-up area, cultivated land, and bare land use/land cover type increased with 351%, 105%, and 41.9% respectively between the year 1979 and 2017.Infrastructural and agricultural expansion, increased demand for wood, local environmental and biophysical drivers, rapid human population growth, economic drivers, technological drivers, policy and institutional drivers, and local socio-cultural drivers were identified as drivers of land use and xxland cover changes. There should be urban disaster risk reduction policies and strategies at national level which guide local urban disaster risk reduction interventions and the principles of good governance should be properly practiced in governance of urban flooding disaster risk reduction in Ambo town. It is vital to pay attention to the coordination between urban development and flooding hazard and risk through appropriate spatial planning and land use management in Ambo town and its watershed. Keywords: Governance, flooding, land use/land cover, land use management, spatial planning