1. Bitsanis Stathis Abstract of Diploma Thesis
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ABSTRACT OF DIPLOMA THESIS
The subject of this diploma thesis is the implementation of the rainfall-runoff
model MIKE SHE in the mountainous part of Glafkos catchment, which is located
near the city of Patras in Greece. The aim of the project was: (a) to improve the
calibration performed in a previous work (see Siambi, 2012) and (b) to investigate the
differences in the simulation results obtained by using different modules of MIKE
SHE particularly for the simulation of the infiltration through the unsaturated zone,
the snow melt and the interflow.
In the first chapter of the work the geological, morphological and land use
conditions in Glafkos catchment, as well as the available data, i.e. daily values of
precipitation, temperature and river discharge are presented. Further, an evaluation of
the data for the selection of the calibration period has been performed.
The second chapter describes the concepts used in MIKE SHE for the
simulation of the different processes.
The third chapter describes the modification of different parameter values, in
order to improve the simulation results obtained in a calibration performed in a
previous study (see Siambi (2012). The particular purpose was to eliminate runoff
peaks appearing in the simulated hydrographs, which have not been observed. It was
found that by increasing the value of the detention storage, a significant improvement
has been achieved. Note that for the evaluation of the simulation results the Nash and
Sutcliffe type criteria based on Q, i.e. CrQ, square root Q, i.e. Cr and logarithm of
Q, i.e. CrlogQ, as well as the bias, i.e. CrWB (see Oudin et al., 2006) have been used.
For the simulation of the infiltration through the unsaturated zone in the
previous chapter 3 we used the module “2-Layer Water Balance Method”. In the
fourth chapter, we present simulations based on the module “gravity flow”. For this
module a column of the unsaturated zone must be discretized and the soil properties
characterizing the water content and the hydraulic conductivity under unsaturated
conditions must be defined for each cell of the column. We found that the simulation
results, i.e. the values of the evaluation criteria (see above) could not be significantly

2. Bitsanis Stathis Abstract of Diploma Thesis
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improved. The computational effort for the simulations, in which the gravity flow
module is used, is significantly larger than that for the 2-Layer Water Balance
Method.
In chapters 3 and 4 the differences in the elevation of the different parts of the
catchment have not been considered. The elevation of the whole catchment has been
assumed equal to the mean altitude. In the fifth chapter, we investigated the effect of
the differences in the elevation of the different parts of the catchment. For this
purpose (a) we divided the catchment into four zones of different elevation and (b) we
used for the simulation of the interflow a cascade of four interflow reservoirs. In a
next step we grouped the four zones in to pairs of zones and we considered that the
temperature in each pair of zones is different. The time series of the temperature have
been calculated by using a rate of temperature decrease for increasing altitude. The
results show that the consideration of the differences in the elevations, both
concerning the number of the interflow reservoirs as well as the temperature
differences are important for the simulation.
In the sixth chapter, we compared different methods to simulate the melting of
snow. The investigation was focused on a definite year with significantly larger
annual depth of snow than the other years in investigated period. It was found that the
results of two methods, namely (a) the degree-day method and (b) the combination of
the degree-day method with thermal melting, do not show significant differences.
In the last chapter, a summary and the most important findings concerning the
overall behavior of MIKE SHE for the conditions in Glafkos catchment are presented.