Actual Evapotranspiration Estimation Using Remotely Sensed Data and Hydrological Model: A Case Study Of Gilgelabay Catchment
| dc.contributor.advisor | Dereje, Hailu (PhD) | |
| dc.contributor.author | Genet, Abdi | |
| dc.date.accessioned | 2021-02-23T05:08:24Z | |
| dc.date.accessioned | 2023-11-11T08:32:33Z | |
| dc.date.available | 2021-02-23T05:08:24Z | |
| dc.date.available | 2023-11-11T08:32:33Z | |
| dc.date.issued | 2015 | |
| dc.description.abstract | In order to get reliable qualitative and quantitative information about a potential of water resource in a catchment it is important to assess and evaluate the spatial and temporal variation of actual evapotranspiration by applying SEBS algorithm and SWAT hydrological model and eventually compare with MODIS ET. This is one of the motivations for evaluating the spatial and seasonal dynamics of actual ET for the Gilgel Abay catchment using energy balance algorithm and hydrological model. Spatially distributed actual evapotranspiration (ETa) values were estimated using Surface Energy Balance System (SEBS) approach and the Soil and Water Assessment Tool (SWAT). The input data for SEBS and SWAT were acquired from different sources with different spatial and temporal resolutions. The dynamics of ETa was assessed only for the selected dry years (2009) and wet year (2005 and 2007). Moreover, the analysis was based on the nine selected days of those years having a cloud cover less than 30%. The estimated ETa values were also compared with MOD16 ET at sub-catchment scale. SEBS based estimated daily actual ET eventually were compared with MODIS ET and SWAT actual ET estimates to assess the temporal and spatial variability in the catchment. The result showed that the mean value of SEBS daily actual ET during those days reached up to 5.9 mm/d (Jan-01-2005), 5.5mm/d (January 10, 2007) and 5.1 mm/d (March 12, 2007). In distinction as it observed from the results during wet season days the SEBS estimated actual ET is relatively lower and highly variable spatially. The mean actual ET for day of the year [DOY] 253- 2009 is 8.8 mm/d, DOY 336 - 2007 is 5.8 mm/d and DOY 330- 2009 5.1 mm/d which shows the spatial variability resulted due to heterogeneity of the vegetation cover during the wet season. Similarly, the long-term mean annual actual ET derived from previous hydrological studies using SWAT compared well with MODIS ET over the terrestrial part of the catchment. The evaluation of the wet season actual ET from 2000-2010 from MODIS and SEBS was compared with SWAT and the result showed that a good correlation. Thus, overall MODIS ET product showed good agreement with results from the SWAT models both in magnitude and spatial variability | en_US |
| dc.identifier.uri | http://etd.aau.edu.et/handle/12345678/25187 | |
| dc.language.iso | en_US | en_US |
| dc.publisher | Addis Ababa University | en_US |
| dc.subject | Gilgel Abay | en_US |
| dc.subject | ET | en_US |
| dc.subject | ETa | en_US |
| dc.subject | Remote Sensing | en_US |
| dc.subject | MODIS | en_US |
| dc.subject | SEBS | en_US |
| dc.subject | SWAT | en_US |
| dc.title | Actual Evapotranspiration Estimation Using Remotely Sensed Data and Hydrological Model: A Case Study Of Gilgelabay Catchment | en_US |
| dc.type | Thesis | en_US |