Analysis of future rainfall pattern in Mahaweli River Basin of Sri Lanka | |
| Author | Imbulana, Kuruwita Arachchige N. D. |
| Call Number | AIT Caps. Proj. no.CIE-16-37 |
| Subject(s) | Rain and rainfall--Sri Lanka--Mahaweli River Basin Climatic changes--Sri Lanka--Mahaweli River Basin |
| Note | A capstone project report submitted in partial fulfillment of the requirements for the degree of Bachelor of Science in Engineering Civil And Infrastructure Engineering, School of Engineering and Technology |
| Publisher | Asian Institute of Technology |
| Series Statement | Caps. Proj. ; no. CIE-16-37 |
| Abstract | Theres compelling evidence accept that climate change is real and has received lot of atten- tion in the recent times. Climate change can impact water resources in many ways due to the intrinsic relationship they share. A river basin has many lives connected to it which may even depend upon it. Therefore it is important to quantify climate change impacts in a river basin to assist the decision making process with regard to the water resource management of the river basin. This study was carried out to assess future rainfall pattern in the Mahaweli River Basin of Sri Lanka till the end of this century. The study used daily rainfall data for the baseline period of 1971 to 2000 of fifteen selected station in the basin. The river basin spreads over portions of each climatic zones of Sri Lanka, Wet, Intermediate and Dry Zones. Fifteen stations were selected so that there are five stations each in each climatic zone of the basin. The future rainfall pattern in the Mahaweli River Basin was projected with the use of three CMIP5 GCMs under two RCPs, RCP4.5 and RCP8.5.The raw GCM data was bias corrected using the quantile mapping method and the bias corrected data were used for further analysis. All three GCMs projected a general increase in rainfall, therefore for rest of the analysis ensemble mean of GCMs were used to discuss the future rainfall patterns in the basin. Future results were discussed in under three periods, near term (2020s 2006-2035) mid-term (2050s 2036-2065) and far term (2080s2066-2095). Several indicators were used to visualize the results more effectively such as, Annual rainfall, monthly rainfall, monsoon seasonal rainfall and also five precipitation indices, namely, CDD, CWD, PRCPTOT, Rx5 and R20mm. The results showed that the annual rainfall increases for the entire basin com- pared to baseline. Except for FIM the SWM, SIM and NEM rainfall in all future time periods increase for the entire basin. CDD were projected to decrease and CWD, PRCPTOT were projected to increase and Rx5day generally decrease. R20mm was projected to decrease for the wet zone of the basin for all future time periods, increase in intermediate zone only in 2080s (decrease in 2020s and 2050s) and generally decrease for the dry zone in future rel- ative to the baseline period. The results suggest that the decision makers should focus on managing and making optimum use of the increased rainfall that is projected to be received in some time periods to compensate for reductions during other periods, to increase the crop yields and hydro power generation. |
| Year | 2016 |
| Corresponding Series Added Entry | Asian Institute of Technology. Caps. Proj. ; no. CIE-16-37 |
| Type | Capstone Project |
| School | School of Engineering and Technology (SET) |
| Department | Department of Civil and Infrastucture Engineering (DCIE) |
| Academic Program/FoS | Civil and Infrastructure Engineering (CIE) |
| Chairperson(s) | Shrestha, Sangam; |
| Examination Committee(s) | Datta, Avishek; |
| Degree | Capstone Project (B.Sc.)-Asian Institute of Technology, 2016 |