This is less a problem than an inquiry into a better way of doing something. I am curious how people might go about selecting, say, all areas less than or equal to 10 feet (from a DEM) that are contiguous to the coastline. The purpose of this exercise would be to map low-lying areas along the coast that may flood during a coastal storm or surge.
Here is an abridged version of how I've been doing this sort of thing:
1) Extract from DEM all values less than or equal to 10 feet using the (raster) clip tool
2) Convert the raster to a polygon using the Raster to Polygon tool
3) Select areas contiguous to the coastline layer:
a) Select all polygon areas that intersect the coast line. Export selection.
b) Add to selection all areas that intersect the new selection. Export.
c) Repeat this process until the difference in the number of attributes from one exported selection
to the next reaches 0.
It's this step "c" that I'm trying to find an alternate method to. It can take up to 20 iterations of this step to select these areas for NYC. It just seems so tedious. I'm really curious how others might go about performing this task.
أكثر...
Here is an abridged version of how I've been doing this sort of thing:
1) Extract from DEM all values less than or equal to 10 feet using the (raster) clip tool
2) Convert the raster to a polygon using the Raster to Polygon tool
3) Select areas contiguous to the coastline layer:
a) Select all polygon areas that intersect the coast line. Export selection.
b) Add to selection all areas that intersect the new selection. Export.
c) Repeat this process until the difference in the number of attributes from one exported selection
to the next reaches 0.
It's this step "c" that I'm trying to find an alternate method to. It can take up to 20 iterations of this step to select these areas for NYC. It just seems so tedious. I'm really curious how others might go about performing this task.
أكثر...