| Title: | Comparison of MODIS and SWAT evapotranspiration over a complex terrain at different spatial scales |
| Authors: | Abiodun, O.O., H. Guan, V.E.A. Post and O. Batelaan |
| Year: | 2018 |
| Journal: | Hydrology and Earth System Sciences |
| Volume (Issue): | 22(5) |
| Pages: | 2775-2794 |
| Article ID: | |
| DOI: | 10.5194/hess-22-2775-2018 |
| URL (non-DOI journals): | |
| Model: | SWAT |
| Broad Application Category: | hydrologic only |
| Primary Application Category: | evapotranspiration assessment |
| Secondary Application Category: | hydrologic assessment |
| Watershed Description: | 44 km^2 Sixth Creek located in the western part of the Mountain Lofty ranges in the state of South Australia, Australia. |
| Calibration Summary: | |
| Validation Summary: | |
| General Comments: | |
| Abstract: | In most hydrological systems, evapotranspiration
(ET) and precipitation are the largest components of the water
balance, which are difficult to estimate, particularly over
complex terrain. In recent decades, the advent of remotely
sensed data based ET algorithms and distributed hydrological
models has provided improved spatially upscaled ET estimates.
However, information on the performance of these
methods at various spatial scales is limited. This study compares
the ET from the MODIS remotely sensed ET dataset
(MOD16) with the ET estimates from a SWAT hydrological
model on graduated spatial scales for the complex terrain
of the Sixth Creek Catchment of the Western Mount Lofty
Ranges, South Australia. ET from both models was further
compared with the coarser-resolution AWRA-L model at
catchment scale. The SWAT model analyses are performed
on daily timescales with a 6-year calibration period (2000–
2005) and 7-year validation period (2007–2013). Differences
in ET estimation between the SWAT and MOD16 methods
of up to 31, 19, 15, 11 and 9% were observed at respectively
1, 4, 9, 16 and 25 km2 spatial resolutions. Based on
the results of the study, a spatial scale of confidence of 4 km2
for catchment-scale evapotranspiration is suggested in complex
terrain. Land cover differences, HRU parameterisation
in AWRA-L and catchment-scale averaging of input climate
data in the SWAT semi-distributed model were identified as
the principal sources of weaker correlations at higher spatial
resolution. |
| Language: | English |
| Keywords: | |