Geoscience Reference
In-Depth Information
Fig. 5 MFD flow to all
downslope neighbours (Laura
2001
)
Fig. 6 D? algorithm model
(Smith et al.
2009
)
Fig. 7 D8 water flow
direction (Smith et al.
2009
)
that is in all directions, from high to the lower area pulled by the gravitational
force but this model only allow for eight flow direction due to the limitation of
raster based contacted-neighbour pixels.
2.3.1 Limitations of D8 Algorithm
The D8 algorithm is a well-known flow direction algorithm for SFD and able to fit
many application requirement as well as water modelling in hydrology. There are
many advantages of D8 algorithm, for example, it is a very important model at the
valley by producing many parallel flow lines and yet solved many problems within
the boundaries of the catchment area (Wilson
2002
) Nevertheless, some questions
have arisen on the accuracy of this only eight direction options in SFD, especially
for the D8 algorithm.
There are several limitations of D8 algorithm, which was identified by water
related researchers such as:
