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Messages - kfreeman

Using SLAMM / Water cell with no elevation
December 16, 2011, 07:10:06 PM
In a scenario: I have a vegetation grid cell coded as a water value: 15, 16, 17, 18, or 19 and the corresponding cells in the DEM and slope rasters are NoData.
Is that cell used to calculate fetch? Is that cell used in determining adjacency to water?  Or is that cell in the Blank total?
Using SLAMM / Mangrove threshold
November 11, 2010, 05:30:10 PM
What is the threshold/criteria SLAMM uses to determine an area to be tropical and everything converts to mangrove?
Model Formulation & Parameters / Re: Salt Elevation
September 28, 2010, 02:19:02 AM
Quote from: elarson on September 07, 2010, 05:49:38 PM
We typically multiply the GT by the percentage of MHHW where water reaches at least once every 30 days, and divide by 2.  So, for the Chesapeake Bay region -- where this percentage is around 133% -- the calculation would be (GT)(1.33)/2.

I hope that answers you question.


The technical documentation states that the salt boundary is defined as the elevation that is inundated by salt water less than every 30 days.  So, as an example, if I download tide data from NOAA and calculate that elevation to be 1.1 meters, I would then put 1.1 in as the Salt Elevation parameter.  The formula stated above is different than what is in the documentation.  Would you please clarify the calculation for salt boundary?  If there is more than one method, how does one choose what is most appropriate?
Using SLAMM / Re: Time and time steps
April 26, 2010, 06:47:02 PM
Colleagues have suggested trying the following to accomplish a hindcast.   Our NWI map was created in 1983 - 1984 and our NED is from approximately 1999. We were wondering if we could accomplish the equivalent of a hindcast using the following technique: Instead of entering 1984 as our map date, we would enter 2010. Then we would subtract 26 (actually rounding to 25) years from each of the resulting outputs to view results for our period of interest.  Thus, the model output for 2035 would actually represent the change in condition from 1985 through the year 2010.   What do you think of this approach?
Using SLAMM / Issues with screen input/output
April 19, 2010, 05:04:39 PM
I have come across 3 issues with screen input and output.  A scenario with 5 year time steps until 2040 was run and saved to a .SLAMM6 file.  I used Load Simulation to load it again, and then changed the time step to 25 years and end date to 2100.  My eye happened to catch the fact that the 2100 got changed back to 2040!  I tried a few more times to change it to 2100, but it  would not stay.  I let the run continue (25 year time step to 2040).   It did process to year 2025, and then got  a range check error.  I have gotten range check error  before on previously  working simulation runs, and I am wondering if this was the problem.

When SLAMM tries to paste a map to Word (2007), it opens Word, then gets an error "Runtime error copying map to Microsoft Word for year X.  Retry writing map to Word? Yes or No?"  Yes would get the error  message again.  No would produce no map.  I found that if you paste a screen shot (or probably any object)  into Word and THEN answer yes, the maps paste without any further problem.

In my model input, I have a  large area coded as Open Ocean.   However, on both the maps pasted into Word and on the screen,  the Open Ocean appears white.  The default Legend has it symbolized as dark blue.  Why is that happening?
Using SLAMM / Re: MTL to NAVD88 Correction
April 19, 2010, 03:44:34 PM
We did a SLAMM run and calculated the NAVD_correction as MTL-NAVD88 = -0.067.  This gave us a poor T0 result with lots of changes.  We recalculated with vdatum and got a result of -0.5066, which gave a a much improved T0 result.  However, we had used "MLW" as the Input Vertical Datum to get that result.  When we use "MTL" as the Input Vertical Datum, we get -0.0452, which is a poor T0 result.  Any ideas about why this is happening or what we should look into? 
Using SLAMM / Error using Count button
April 01, 2010, 01:49:30 PM
I am trying to run SLAMM 6, but cannot get to enter Map Attributes. All the txt files are the same dimensions in the same directory with 4GB memory in my computer.  5 meter cell size, so it ends up being ~30 million cells.  First, I entered the file names and site parameters,  and when I tried to enter Map Attributes I got a range check error.  I looked up the forum advice for that, exited the model and tried again using the ignore high elevations and water.  The count was about 23 million cells and ~1.3GB memory usage.  But, in Map Attributes I got a Error creating map in memory, write map to disk instead?  Clicking Yes or No gave me a Range Check error. Now, however, when I try it again, the Count button will only work on "Track all cells".  If I try the other options for Count button, I get the following error: "Must Include SLAMM Code (NWI) Data File".  Of course, the file is there, and is correctly set up as far as I can tell.  Using "Track all cells", I move on and then I then get the Range Check/Error creating Map problem.  I have tried various things:  renaming, moving files, different computer.  What should I try next?   
Using SLAMM / Time and time steps
March 22, 2010, 09:54:57 PM
We are thinking of running SLAMM using 1983 NWI data and 5  year time steps until 2005.
Would it be valid to compare these SLAMM results to past aerial photography/imagery?
We are looking to see if SLAMM will show tree islands (Swamp) in marshes converting to something else,
changes are visible in the photography.  Our known problem is that our LiDAR-derived  elevation data
is from 2007.  Vegetation correlates highly with elevation, would it be sensible to turn
the preprocessor on in the above scenario?  Thinking about the model's T0 has generated the question,
if the model start date is 1990 and the time step is 25 years, how is the first time step ending in year 2025?