Experiment results

Experiment 1 - Angledool NSW

The first experiment was to map out the flood in Angledool New south wales. It is located nearly 540km south west of Brisbane and the boarder between NSW and QLD. The major river nearby is Narran River and a major flood occurred in March 2010.

The aim of this experiment is to utilise all the images provided to generate flood maps and analyse the floods by using ArcGIS.

After following the methodology mentioned before, 2 flood map for 2 days on march 2010 were generated. The floodwater extent was demonstrated in blue colour. The dense blue colour denotes flatter surface which is flooded by water and they are usually farmlands.

The flood extent was shown after reclassifying the coherence image. The flood extent was shown in blue colour on the map which the majority of the whole region was flooded.

After subtracting the pixel values, the intensity difference image was created. In this map. Blue denotes the positive changes with fresh flood water while the red denotes any negative changes.

Intensity images

Coherence and intensity analyses

Optical images

The optical true colour image on the left and infrared colour image on the right. The true colour image shows the water extent with brown colour due to the flood water Is muddy with the mixture or moisture soils. The infrared image then shows the flood extent in blue colour, while the moisture soils are shown in red colour, as same as the other features.

This is the SES flood extent shapefile overlaid on the basemap. Compared to the previous results, this SES flood extent shapefile only shows part of the flood extent and the flood boundary line is much smoother.

This is the coherence flood extent which was exported onto Google Earth. The flood extent would be correctly lay on the right location in Google Earth With the properly georeferencing the images.

Experiment 2 - Rockhampton QLD

The second experiment is to map out the flood in Rockhampton QLD. This flood occurred a year after the Angledool flood in previous experiment. In early January 2011, the areas around Fitzroy Rover were affected by heavy rain which occurred a month before. Rockhampton therefore was severely affected due to its situated in the river basin.

The aim of this experiment was to utilise the data to generate flood maps and conduct flood analyses.

As same as before, four intensity images were generated and blue denotes floodwater extents.

The coherence images were classified and the flood extents were mapped out after manually clearing all the noises around. From the above images, most of the surrounded areas in Rockhampton were severely flooded and all the facilities and infrastructures were affected. The roads and the local airport were closed due to they were totally filled with floodwater as well.

Intensity images

Coherence and intensity analyses

Intensity difference images

GIF animation

This GIF animation consists of four different dates in January 2011. Rockhampton area in these dates were flooded and we can see the flood condition with the extent comparisons. According to the changes, the 5th of January was likely to be flooded with the maximum amount of floodwater. In such case, its believed that 5th of January was in flood peak or the closest to the flood peak.

The intensity difference images were generated as well by following the same steps in methodology. Blue colour denotes positive changes while red denotes negative changes.

University of New South Wales

Integrated Remote Sensing For Flood Mapping

Export to Google Earth

GIF animation

The last result of experiments 1 would be a GIF animation. This is the animation of two consecutive flooded days which visually shows the expansion of the floodwater.

Data

Techniques

1. Intensity image on 19 March 2010

COSMO-SkyMed constellation satellites

2. Intensity image on 20 March 2010

COSMO-SkyMed constellation satellites

3. Coherence image between 19 and 20 March

COSMO-SkyMed constellation satellites

4. Optical True Colour

LPI ADS40 aerial platform

5. Infrared colour

LPI ADS40 aerial platform

6. Flood extent shapefile

NSW SES helicopter GPS survey

Data

Techniques

1. Intensity image on 4 January 2011

COSMO-SkyMed constellation satellites

2. Intensity image on 5 January 2011

COSMO-SkyMed constellation satellites

3. Intensity image on 12 January 2011

COSMO-SkyMed constellation satellites

4. Intensity image on 13 January 2011

COSMO-SkyMed constellation satellites

5. Coherence image between 4 and 5 January

COSMO-SkyMed constellation satellites

6. Coherence image between 12 and 13 January

COSMO-SkyMed constellation satellites