Evaluation of uncertainty in climate change projections on runoff for wami river sub-basin
| dc.contributor.author | Wambura, Frank Joseph | |
| dc.date.accessioned | 2020-04-29T09:25:05Z | |
| dc.date.available | 2020-04-29T09:25:05Z | |
| dc.date.issued | 2013 | |
| dc.description | Available in printed form, East Africana Collection, Dr. Wilbert Chagula Library, Class mark (THS EAF GB656.2.H9W35) | en_US |
| dc.description.abstract | River runoff is an inherently uncertain natural process, in which the reliability and credibility of its prediction under changing climate cannot be guaranteed without properly incorporating uncertainty bounds of the climate change projections. In this study runoffs in the Wami River Sub-basin were simulated at various levels of uncertainty using a physically based and distributed rainfall-runoff model, SWAT. In addressing future water uses; the domestic, livestock, irrigation and industrial water demands in the sub-basin were projected to year 2039. Precipitation was used as the changing climatic variable for prediction because it is more sensitive than temperature by an average of 96% sensitivity index. To factor in effects of climate change, a total of 24 GCMs from CMIP3 database representing 20 century precipitation were interpolated into 45 sub-catchments in the sub-basin and evaluated for their skills against threshold of 75%. Then scenario A2 precipitation variables of the 4 skilled GCMs were downscaled by Non-linear delta method to the 45 sub catchments in the sub-basin. The uncertainty bounds of precipitation changes were estimated from skilled GCMs using a fuzzy extension principle and they were used to customize climate in SWAT model to generate the uncertain runoff bounds. Runoff bounds predict high increase of flow in March-April-May period and slight increase or decrease in November-December period. At the worst-case scenario (100% uncertainty), the average annual flow change from the sub-basin is predicted to range between +149% and +724% from baseline flow, but the flow change is also predicted to range between -34% and +265% from baseline flow in November- December-January period. | en_US |
| dc.identifier.citation | Wambura, F. J. (2013) Evaluation of uncertainty in climate change projections on runoff for wami river sub-basin, Master dissertation, University of Dar es Salaam. Dar es Salaam. | en_US |
| dc.identifier.uri | http://41.86.178.5:8080/xmlui/handle/123456789/10466 | |
| dc.language.iso | en | en_US |
| dc.publisher | University of Dar es Salaam | en_US |
| dc.subject | Climatic changes | en_US |
| dc.subject | Rainfall runoff | en_US |
| dc.subject | Hydrologic models | en_US |
| dc.subject | Wami river | en_US |
| dc.title | Evaluation of uncertainty in climate change projections on runoff for wami river sub-basin | en_US |
| dc.type | Thesis | en_US |