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Messages - Amy Polaczyk

1
Using SLAMM / Re: Cell Size
December 03, 2015, 03:32:11 PM
Hello Somayeh,

The cell size is defined in the header of the input rasters. Any size is fine, but  all the input data must have the same cell size.  Also, the unit must be meters.

For example, the header for a recent project we ran looked like this:

ncols 11763
nrows 17422
xllcorner  4.08044000000000E+0005
yllcorner  4.10364100000000E+0006
cellsize 6.096
nodata_value -99

Hope this helps.

Amy
2
Using SLAMM / Re: output problem
November 16, 2015, 10:16:25 AM
Hello Somayeh,

Are you using the 64-bit version? Can you tell me about how long it takes to run a timestep in your current model setup? While SLAMM does execute faster than a hydrodynamic model, it can still take a few hours to run a simulation.

Best,
Amy
3
Using SLAMM / Re: SLR Scenario
November 12, 2015, 09:55:12 PM
The 1m SLR you specified is 1m by 2100. As stated in the technical documentation: "SLAMM will scale the A1B scenario to estimate time-varying Sea Level Rise that will result in the specified degree of eustatic SLR by 2100."  So the actual SLR at the timsteps before 2100 will be similar to those shown in Figure 1 of the tech. doc.

Hope this helps. 

Cheers,
Amy
4
Using SLAMM / Re: output problem
October 21, 2015, 12:27:54 PM
Somayeh,

The simulation will not be successful without tidal water included (open water or estuarine open water). Tidal water must be included in order for the model to understand where the inundation is coming from and predict the effects of SLR accordingly.

Regarding the depth profile, I am unable to open the  files you sent, so I cannot address this issue. Can you send your *.SLAMM6 project file? Maybe that will help me answer your question.

Amy
5
Using SLAMM / Re: output problem
October 19, 2015, 01:12:37 PM
Hello Somayeh,

I'm not able to open your files in SLAMM or QGIS, but by looking at them with a text editor I was able to identify a few issues:

1. You have 11 columns an 507 rows with 1m cells, what you are seeing looks correct as far as the shape and size of your area - long and skinny.

2. There is no water in your wetland layer. You will not have any change without tidal water included.

3. You haven't specified the corner info in your file headers. You should make sure you have a uniform projection when sampling your input data from your source layers.

Cheers,
Amy
6
Using SLAMM / Re: Full Gulf Rasters
September 29, 2015, 02:41:50 PM
Hi Brian,

The whole gulf rasters are really large, but you can also download the results as the individual study areas. I suggest this approach:

Go to http://www.warrenpinnacle.com/prof/SLAMM/GCPLCC/

Check the report to determine the names/numbers of the study areas you need (pg 8-11)

Download the new (aka gap) areas using the second link in the Quick Links (Final Model Raster Output). You'll have to download all the new areas and pick out the ones you need.

If there are "existing SLAMM areas" (i.e., they were run before this project) in your AOI, you can download them using the GIS repository link under Task 2. If you want the newest outputs for these let me know which areas you need via email.

Of course let us know if you need additional support.

Cheers,
Amy
7
Using SLAMM / Re: Elevation analysis issue
October 15, 2014, 08:03:47 PM
Correct. The elevation pre-processor is only needed when the elevation data is derived from contours.

Glad it was an easy fix!

Cheers,
Amy
8
Using SLAMM / Re: Elevation analysis issue
October 15, 2014, 06:25:09 PM
Hello!

Do you have the pre-process wetland elevations set to true? The elevation analysis will not run when the pre-processor is used.

Best regards,
Amy
9
Using SLAMM / Re: variable tide range
July 02, 2014, 10:33:41 PM
Glad you got it sorted out!

Cheers,
Amy
10
Using SLAMM / Re: variable tide range
July 02, 2014, 11:17:28 AM
The procedure (which should be described in the Users Manual) to add input subsites is to click 'add subsite' then click 'define boundary'. At that point you can define your subsite polygon. 
11
Using SLAMM / Re: variable tide range
July 01, 2014, 03:22:06 PM
Currently input subsites can only be specified in the Map Attributes view; However, it is not necessary to run the simulation before adding input subsites. Our standard approach is to add all the necessary subsites before running the model calibration steps (elevation analysis, time zero, etc...).

Cheers,
Amy
12
Using SLAMM / Re: variable tide range
June 30, 2014, 04:40:59 PM
Hi Nava,

Yes, the best way to specify the variation in tide range is to insert individual subsites.

Best regards,
Amy
13
Hello Rich,

This is a really good question. In principal, you do not need to model all the way out to the ocean. However, some points to consider:
A) including the ocean will provide important context for your study area. We include the ocean in the gross majority of our simulations.
B) in order to incorporate the effects of erosion it is necessary to include the ocean/land interface (at least 1-cell width of open ocean is needed since erosion is calculated for areas where 9 km of wave set-up is possible, the model will consider the area beyond the 1-cell of open ocean as it had infinite width)

1 meter is a very small pixel size and it may only make sense to output at this resolution if the resolution of the input data the same or higher (1 meter or smaller) and the project is within the memory capabilities of the model (< 4 GB since the model is 32-bit).

Hope this info helps. Please let us know if you have other questions.

Cheers,
Amy
14
Hi Anna,

Are you using the overwash module (i.e. do you have a value in the parameters for the 'frequency of overwash')? Based on the figure you sent, it looks like the results you are seeing are due to overwash calculations. You might try re-running the simulation with the frequency of overwash set to zero unless you have site-specific data for storm frequency and effects.

Hope this helps. Please let us know if you have any other questions.

Cheers,
Amy
15
Hi Marissa,

An interesting paper regarding regularly-flooded marsh that we often refer to is:
McKee and Patrick. 1988. The Relationship of Smooth Cordgrass (Spartina alterniflora) to Tidal Datums: A Review. Estuaries 11:143-151.

Generally we do not concern ourselves with the maximum elevation of the wetland categories unless we are using contour-based elevation data and implementing the elevation pre-processor. If you have LiDAR data, the minimum elevations will be the important parameters to pay attention to.

Hope this helps.

Cheers,
Amy