15 replies to this topic

[bhaslag]

Hi,

I just joined to this website and I know the solution, so if you are still looking for that let me know

Sahar

SAHAR,
I NEED to know how to do this, and fast! I do hope it is simple. I have to present this on Friday. I cant figure out how to do it.
Please help me!
Kim

Probably a bit late with this.

To do a basic sea-level rise analysis, you would need a DEM (digital elevation model) dataset for the area that you are looking at. This data, for New Jersey, is available from the Department of Enviromental Protection GIS website. Other places will have their own data warehouses where they store this kind of stuff.

This dataset is a raster (pixel, squares, however you want to think about it) dataset, which allows us to do raster calculations using the Raster Calculator in ArcGIS. One thing to remember is that DEM comes in meters, so if you want to do things in terms of feet you'll have to use the raster calculator and multiply the map by the conversion factor (3.28 feet in a meter).

Using the raster calculator, you input the level of sea rise that you're interested in. ArcGIS spits out a map of two colors, indicating true and false for the expression you put in. So if you wanted all land greater than or equal to 3 meters, indicating a sea level that would rise up to 3 meters, you would get a map showing True (1) for all that land, and False (0) for the land that would be inundated by water.

That's the most basic. This guy has a good slide show of how he went about a problem similar to yours, I believe.

http://www.slideshar...el-rise-and-gis