| Summary: | Buleleng is one of regencies located in Bali, which potentially threatened
by the sea level rise. This fact requires the availability of the flood map coastal
area as the effort basic of disaster mitigation. The primary data for potential flood
mapping of the coastal area are sea surface heights which are determined from
Satellite Altimetry Envisat data. Supplying satellite altimetry data with better
quality, need to evaluate the results of post-processing data. This research aim to
evaluate post-processing result to generate dynamics sea level data that more
thorough from Envisat altimetry satellite data, as basic data for coastal flood
mapping. The results of post-processing data in this research by testing the
appropriateness of the post-processing result of each geophysics correction
combination model using tidal data that were already passed the data quality
control. In the post-processing steps, combinations of geophysics correction
models were conducted, they are: category I (ECMWF, GIM, FES2004), category
II (MWR, Radiometer, GOT00.2b), and category III (MWR, DORIS, GOT0.2b).
The best combination model was determined based on the results of tests
including RMS error value, product moment correlation, T-test, and visualization.
After the best model was determined, the trend and the sea level rise forecast for
the following years were analysed using regression method. The forecasted sea
level data are defined as �threat data� for year of 2015. The year were chosen
based on practical consideration that is the conformity with the disaster
prevention plan which must be reviewed every 5 years. To give the meaning of the
threat data, then they were visualized through developing a flood map coastal
area using GIS software.
This results show that the best of the combination of geophysics correction
model is category I (ECMWF, GIM, FES2004). The evaluation result values for
category I are RMS error (1,10 m), product moment correlation (0,50), T-test
(0,19), and visually is the most suitable with the tidal pattern. From the chosen
combination of geophysics correction model, Satellite Altimetry data were
analyzed to get the trend of mean sea level rise and to obtain the equation, that is
y = 0,051x + 1,612. The forecasted sea level rise for 2015 is 25,5 cm. The
percentages of the potentially flooded area in the western coastal area in
Buleleng for 2015 is 7,396%.
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