Assessment of green and blue water under climate change : a case of the Harirud- Murghab Basin, Afghanistan | |
| Author | Zadeh, Mitra Safar |
| Call Number | AIT Thesis no.WM-17-05 |
| Subject(s) | Climatic changes--Afghanistan--Harirud-Murghab Basin--Assessment Water--Afghanistan--Harirud-Murghab Basin--Assessment |
| 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-17-05 |
| Abstract | The Harirud - Murghab basin is one of the major basins out of five basins in Afghanistan with 77,604 km2. It consists of four sub-basins (Upper Hari Rod, Lower Hari Rod, Bala-Murghab and Kush wa Kashan Rod). Land cover of the basin is dominated by rangeland and barren area 59.5% and 23.5% respectively. Climate change is the great concern in this regions due to severe drought occurred recently. Studies of climate change in Afghanistan show that the mean annual temperature has increased by 0.6°C since 1960s and it would increase by 1.4 to 4 °C by the 2060s and by 2 to 2.6 °C by the 2090s. However precipitation is expected to change from -31% to +28% by the 2090s. Since about 80% of Afghan’s livelihood depends on rain-fed agriculture and cattle grazing, therefore they are sensitive to available water. Hence, this study aims to assess availability of water under climate change scenarios in Harirud-Murghab river basin. Water availability was accounted based on blue and green water in entire basin, as green water is important component for rangeland and crop production. The climate variables (precipitation, maximum temperature and minimum temperature) were projected under three RCMs and two RCPs (RCP 4.5 and RCP 8.5) for three periods near future 2020s (2010-2039) mid future 2050s (2040-2069) and far future 2080s (2070-2099) for each sub-basins separately. Results are based on seasonal analysis JFM (winter), AMJ (spring), JAS (summer) and OND (autumn). Analysis revels that the precipitation is expected to increase in most climate change scenarios especially in ICHEC under RCP 8.5 in the autumn. The increases vary from 10 to 40mm in different sub-basins and different periods. However it is expected to decrease under REMO-2009 in the winter by 15 to 25mm in all sub-basins in different periods. Maximum and minimum temperature are expected to increase. Increases are more under RCP 8.5. Maximum temperature would expected to increase by 0.81 – 7.1 °C in the winter, 0.46-4.6 °C in the spring, 0.93-6.67 °C in the summer and 0.5- 6.48 °C in the autumn in entire basin by the end of this century. Minimum temperature will increase as well, 0.79 – 8.3 °C in the winter, 0.4-4.3 °C in the spring, 1.16-5.3 °C in the summer and 0.3- 6.7 °C in the autumn under RCP 8.5. The Soil Water Assessment Tool (SWAT) was used to assess water availability. The model was run for 1962 to 1979. Four monthly discharge stations were selected for calibration and validation, each of which was located in one of the sub-basins. In generally, the model showed a good performance with R2 > 0.85 and NSE> 0.70 for calibration and R2> 0.80 and NSE> 0.60 all discharge stations.The calibrated and validated model was run for the base period (1976-2005) as well as for all RCMs and RCPs in three periods. Water availability was measured as blue and green water in the entire basin. Blue water will increase in CNRM-CM5 and ICHEC in the entire basin, while it would decrease significantly in the upper part of the basin in REMO-2009 under RCP 8.5. Green water is likely to increase in ICHEC under RCP 8.5 and decrease in REMO-2009 and CNRM-CM5 models. Green water storage would expect to increase in CNRM-CM5 more than other models in the future. The uncertainty of distribution of green and blue water was high as the variation in precipitation projection was high. This study can be a benchmark to further advanced study in the basin. |
| Year | 2017 |
| Corresponding Series Added Entry | Asian Institute of Technology. Thesis ; no. WM-17-05 |
| 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;Jourdain, Damien |
| Scholarship Donor(s) | AFG Western Basins Water Resources Management Project;AIT Fellowship |
| Degree | Thesis (M. Eng.) - Asian Institute of Technology, 2017 |