Quantifying uncertainties in climate projections on hydrologic modeling in the Tamakoshi River Basin, Nepal | |
| Author | Aryal, Anil |
| Call Number | AIT Thesis no.WM-16-11 |
| Subject(s) | Hydrologic models--Nepal Climate--Nepal |
| Note | A thesis submitted in partial fulfillment of the requirements for the Degree of Master of Engineering in Water Engineering and Management |
| Publisher | Asian Institute of Technology |
| Series Statement | Thesis ; no. WM-16-11 |
| Abstract | This research was carried out Tamakoshi River Basin, a sub - basin of the Koshi River Basin in the NE of Nepal. This research uses multiple climate and hydrological model so as to simulate future climate and discharge in the basin outlet. Further, the simulated results were analyzed for the quantification of the sources of uncertainty in simulating future climatic variables and discharge at the outlet. Climatic parameters temperature and precipitation of the study area are projected t o change in near ( 2010 - 2039), mid (2040 - 2069) and far (2070 - 2099) future. Both the minimum and maximum temperature are about to change by a significant amount. The maximum temperature is about to rise upto 1.75 0 C under RCP4.5 and upto 3.52 o C under RCP8.5 whereas the minimum temperature is expected to rise by 2.1 o C under RCP4.5 and 3.73 o C under RC P8.5 by the end of the 21st century. The precipitation in the study area is expected to change by - 2.15% under RCP4.5 and by - 2.44% under RCP8.5 scenarios. Both the minimum and maximum temperature is expected to rise in each three - time window namely near future, mid future and far future whereas precipitation is supposed to decrease in each time window. The major source of the uncertainty for the climatic parameters being the climate model, the change in the climatic parameters are ubiquitous. The discharge in the study area were projected by using two hydrological models namely SWAT and HEC HMS. The projection of the discharge revels that the future discharge in the river is expected to variate by small amount when SWAT is used as the hydrological model and decrease when HEC HMS used as the hydrological model. Under REMO climate model the discharge in the river is expected to variate by large percentile. While projecting the future river flow both the climate models and hydrological model share large amount of uncertainty towards the total uncertainty. The uncertainty because of the hydrological models are more pronounced during the dry days whereas the uncertainty due to climate models are more pronounced during the wet days . Inter - comparison of the impact of the different climate models revels that the REMO climate model predicts higher uncertainty in prediction of the precipitation and eventually the future discharge and maximum probable flood. Thus quantified uncertainty was analyzed and some graphical methods were adopted to communicate the uncertainty results to the planners a developer. Citing the flood as a consequence (fitted using Gumbel method) of the effect of the change in climate, the result of the uncertainty was tried to communicate projecting the expected flood under different return period. The projection revels that the climate model REMO has higher uncertainty in flood projection. |
| Year | 2016 |
| Corresponding Series Added Entry | Asian Institute of Technology. Thesis ; no. WM-16-11 |
| Type | Thesis |
| School | School of Engineering and Technology |
| Department | Department of Civil and Infrastucture Engineering (DCIE) |
| Academic Program/FoS | Water Engineering and Management (WM) |
| Chairperson(s) | Shrestha, Sangam |
| Examination Committee(s) | Babel, Mukand Singh;Andrias, Sanyogita;Tawatchai Tingsanchali |
| Scholarship Donor(s) | WEM Sponsorship - Asian Institute of Technology Fellowship |
| Degree | Thesis (M. Eng.) - Asian Institute of Technology, 2016 |