Week 3: Hurricanes

The purpose of this project was to assess and remediate the damage caused by the 15-foot storm surge that hit the Mississippi coast during Hurricane Katrina. The objective was to determine how to allocate disaster aid and redevelopment resources. Each of the following exercises shows the steps taken to determine how resources will be allocated.

The purpose of this first exercise was to create a map of the coastal counties of Mississippi that displayed the elevation, places, types of water, barrier islands, and hydrography. This amp allowed for examination of the spatial distribution of features. As can be seen in the map, there is an extensive network of rivers throughout the three counties. There are areas of vast mash networks from central to lower Hancock County and from central to western Jefferson County. A majority of the lower portions of the three counties, including all of the barrier islands, are of low elevation. A majority of the population, as determined by location of places, lies along the coast or within areas of low elevation next to rivers and/or marshes. From this map, it can be hypothesized that due to the overall low elevation, the extensive networks of rivers, and the amount of wetlands, a large storm surge could be devastating to the area. The storm surge itself would cause damage, however, the storm surge will travel up the rivers and into the wetlands and cause massive flooding in the area.

This next image contains data required for both Deliverable 2 and Deliverable 3. The purpose of this exercise was to determine a quantitative analysis through the identification of the land most affected by the storm surge and its land-cover type. The first step in the exercise was to calculate the amount of flooded land. This was done by multiplying the elevation layer by 3.28 to determine elevation in feet. Next, the elevation that was less than or equal to 15 feet was selected to display to extent of flooding. From this a flooded land layer was created. The landcover layer was then added, reclassified, and multiplied by the flooded land layer to create a flooded landcover layer. The flooded landcover layer was then reclassified to display the type of landcover that was flooded. The next step was to create a bar graph showing the percentage of total flooded land by landcover type.


The purpose of this next exercise was to prepare a map showing the spatial distribution of infrastructure and health facilities and determine the extent of damage to the facilities. As can be seen in the map, a majority of the churches as well as every hospital in the area was located along the coastal area. It is believed that the churches and hospitals in the area were all damaged of destroyed by the storm surge. Major highways as well as the barrier island were washed over or destroyed as well. In order to allocate resources there must be a way to get them where they need to be, therefore, the first step in allocating resources to the area would be to clear and restore roads. The next step would then be to restore medical and emergency facilities.

The purpose of this final exercise was to calculate the acres and square miles of the flooded areas. This information allows for damage assessments. This was easily done by adding an acre and square mile field to the flooded landcover attribute table and calculating the fields.

Week 2: Earthquakes

In this exercise data stored in the county and MMI layers was used to analyze the population, interstates, and railroads that are likely to be effected by a given earthquake. The Area Proportion technique was used to redistribute the spatial values throughout an area. This was done by first calculating the population density of each county. By determining persons per meter it is possible to even distribute the population throughout the county, allowing for more accurate results. Next, the county layer and the MMI layer were overlayed to obtain a CountyMMI layer to detemine which counties are within the MMI Zones. The population was then adjusted in the CountyMMI layer and summarized by its sum based on the MMI layer to reflect the population of each MMI layer. Next, using the MMI scale, interstates and railraods at risk where selected and also displayed on the map.

The purpose of this next exercise was to analyze the pattern of building damage resulting from the Northridge Earthquake in Southern California. First, the Building Status layer was used to symbolize building damage. Then, using the Kernel Density tool, it was possible to determine and analyze the density of only damaged buildings (shown on map in blue). Finally, peak ground acceleration and peak ground velocity were interpolated for comparasion to building damage. Note: Classification values were changed to five breaks to minimize space on legend.

The next exercise was used to examine the spatial distribution of aftershocks. This was done by exporting earthquake catalog data into a Northridge Aftershock layer. From the aftershock layer the main shock was selected and and made into a layer. Significant earthquakes with a magnitude of 3.0 or higher were then symbolized.

The purpose of this last exercise was to examine the temporal distribution of the Northridge aftershocks. This was done by summarizing the DaysAfter field by maximum magnitude of aftershocks and then exporting and creating a graph to show the amount of aftershocks following the main shock.