Natural Hazards - Hurricanes

Applications in GIS - Mod 4

In October of 2012 Hurricane Sandy hit the northeast coast of the United States with devastating consequences.  This week's lab was to create two different maps of this event.  The first showing Hurricane Sandy's track from it's inception to it's end stage and the second, a damage assessment for just one side of one street impacted by the storm.

This map shows the path Hurricane Sandy took and the ten states and District of Columbia that were affected.  We started by creating a polyline feature class from the points of the x,y values we added to the map from a table.  We next created a new symbol to represent the storm and used the Unique Values option in the Symbology Category display the different levels of the storm in different colors.  Using the Expression Window on the Labels tab we were able to display both the miles per hour of the winds and also the barometric pressure at each of our points.  This provided a little more information than the category of the storm at each location.  The last step was to add Graticules to the map.  This was my first time working with graticules and that took a little getting used to.  I didn't want the lines to overwhelm my drawing, but there was a fine line between not overwhelming and not showing up.  I had to adjust the color of the lines a few times to get that right.  With that done it was just a matter of adding the labels for the states and countries then the map elements and it was done.

Next on the list was creating a map showing the before and after images of a block in Tom's River New Jersey and assess the damage done to the homes on that block.  This we started by creating a new geodatabase, a feature class dataset and a couple raster datasets to store the data we'd use or create for this portion.  We also created an Attribute Domain.  This allowed us to specify what kind of information would be acceptable to add to the attribute table of the feature class we were creating to identify the damage done to the homes in our area of study.

Up to this point thing were pretty simple.  The difficult part came in trying to determine how much damage had been done to the property and what caused that damage.  The "before Sandy" image was pretty bright and clear, with the houses all very well defined.  The "after Sandy" image, however was darker and not nearly as easy to distinguish details.  Plus it was left up to us to use our own best judgment with no criteria for what constitutes major damage, minor damage, or what has just been affected.  Affected?  What does that mean?  That there was just some level of damage?  Or nothing happened to this house, but the property value is now trashed because everything around it is destroyed?  So it was a guessing game I wasn't really comfortable playing about something so serious.

Looking at the houses from overhead it was difficult to tell what if any damage was done to them, other than the ones that were obviously completely destroyed or moved from where they had originally been.  But one thing that was pretty clear was the inundation was more likely to be the cause of damage than the wind.  There were some houses that appeared to have some damage to the roof, but just about all of the houses seemed to have mud and debris pressed up against them.  I had to assume most of them had gotten damaged to some extent from that.  It was rather astonishing to me that the house closest to the coast had no visible damage from the image.  I'm sure it had to have had some damage from the inundation since it was first hit with it, but looking at it from overhead it would almost appear as though it had survived the storm unscathed.