Hi,

I am working in northern Maine. I am fiddling with my salt elevation and finally got the initial condition/1983 (my NWI year) to practically match in my region. Yay! I initially started with 8.6 m (the highest spring tide on historical NOAA tide sheets) for the salt elevation, but realized that was incorrect after reading the forum, so based on 4.11 m I ran it again. I used the GT from NOAA (5.87)/2 x 1.4 (the average to multiply by per the forum), as per the forum technique, to get 4.11. This is close to what was used by the FWS in this region on two SLAMM studies (3.99 and 4.08).

Although this helped my problem- two low spots in my lidar were converting from undeveloped dry land to transitional marsh and ocean beach- it still was way over a 5% difference (which I have read in this forum is the cutoff for more accurate results). So I played around with the elevation pre-processor and it looked as if a value of '2' m would work. So I used it, and now my initial condition (time zero) and 1983 match! However this number is not really 'science' but an educated guess; is that acceptable when running the model? If they match up does that mean I 'guessed' correctly? I am assuming (from other posts too) that my salt elevation is not in line with my elevation data. This region has very high tides, could that have something to do with it? Thanks for any advice or ideas!

Caroline

Hi,
I am wondering if anyone has a script or tool that will batch convert my numerous SLAMM ASCII output files to raster? I tried one but the file names are more than 13 characters so it wouldn't work. In future versions I would like to see the output files in raster already so they don't need to be converted to raster. Also it would be nice that the names were automatically output to less than 13 characters. Thanks!

Caroline

Hi Jonathan,

I am doing some SLAMM modeling near Eastport Maine (on the Passamaquoddy Indian Reservation). I read the Moosehorn and Petit Manan NWR reports to find local parameters. The closest accretion data I could find was in Cobscook Bay from the referenced journal article in the NWR studies by Goodman et. al. Nowhere in the reports does it say where the erosion rate parameters are from. Marsh, swamp and tidal flat erosion respectively used throughout the subsites are 1.8, 1 and 0.5 m/yr. Where did these come from? I am assuming they are for this local region?  Thanks.

Caroline

Hi,

I am creating my own impervious layer, as the NLCD layer is not as current or detailed as my ortho-photo. Do I need to include roads in the impervious layer? Thanks.

Caroline

hi,
I am using C-Cap data instead of NWI to convert to SLAMM codes. Please advise if these would be the correct codes. I am mostly unsure of the last code (CCAP 23) Thanks. Caroline

CCap                                                                    SLAMM
2-5,           developed                                                    1
6-12, 20     natural areas, bare land                                  2
13-14         paulustrine scrub/schrub/emergent wetlands      3
15              paulstrine emergent wetland                           5
17              estuarine scrub/shrub wetland                        7
18              estuarine emergent wetland                           8
19              unconsolidated shore                                  11
21              open water                                               17
23              estuarine aquatic bed                                 20

hi Jonathan,

I am happy to report I can run my 21,177,910 cel sized NC map that uses 1.24 gb with the updated version (it would crash in 6 although it ran in 5). I unclicked the soil saturation and I don't have streaks - this was a major problem before.  Thanks.

I can't get it to write to Word however (same error as others) even using the workaround mentioned in this forum. It also tells me I am out of memory when I attempt to set the attributes so that part doesn't work. Is this necessary? My output looks reasonable. Looking forward to the 64 bit compatible version so it doesn't take so long to run.

Caroline

hi,

I ran Slamm 6 with the NWI photo date turned off and my results were a bit different than when I ran it with it checked on. My initial condition and photo date outputs were exactly the same when I had it off. I am wondering if this is another good way to 'error check' the input?

Caroline

I ran the elevation analysis in Slamm 6 and have the statistical output. I am unclear what it all means though. 

The output table shows minimum elevations from -1 (estuarine beach, tidal flat, ocean beach and inland shore) to 1 (should I have negative values? How are the stats helpful? I am not clear what I should be comparing or looking at in those columns.

My initial condition (3 meter dem 2005, nwi 2006) and 2006 files have similar output except 2006 has alot more Estuarine Beach and an inland open water pond converts partly to esturine open water (that can't be accurate).

Also some of the code 20 (irregular flooded marsh) is converted to code 8 (regular flooded marsh), when I look at the lidar it follows the code 20 that was converted, so maybe that is more accurate?

Code 6 is reduced (I only have a small area in this category) in the 2006 output vs the initial condition. I read somewhere in the manuals that that code usually needs to be adjusted. How do I adjust it? or any of the others?

When I ran Slamm with a 10 meter DEM, only the beach was reduced significantly between the initial condition and the first year (2005 in that case).

I am also wondering how the elevation graphics tools help. I have looked at the profile and 3d view- should they be smooth? When I ran my 10 meter dem in slamm the tool showed smooth elevations with the preprocessor set to false. When I set it to true the elevations were up and down where roads etc were located in the marsh. Which is correct? I don't have any dikes and I 'burned' the impervious layer (1 and 2 slamm codes) into the nwi slamm layer as mentioned in one of the manuals.

one other question: I set my run using lidar data to 0 for frequency of large storms since I read that pertains to barrier islands and I have no barrier islands nearby. But is that accurate? There are big storms in the winter here.

I hope this makes sense. Thanks for your help.

caroline

hi,

I have read through the posts and technical manuals and I am still not clear about how V-Datum works or if I should be using it. I converted my offshore raster data to points (for Carpinteria Marsh in CA) per the V-Datum manual and then ran through V-datum. I subtracted the output elevations from the input DEM and the values were all the same (0.83 m) which is exactly the same parameter as the NAVD88 correction I input into my header file from NOAA. So why would I need to use V-Datum? To use it would I then convert the points back to raster (with land as no data?) and input into Slamm 6? How is this useful if all the values are the same?

V-datum also can integrate land and sea but the DEM I am using (and also one I am using in NC- Beauford area) has already integrated the ocean and the land together (both are using vertical datum NAVD88). If I did need to do this I am unclear how I would go about it. Thanks.

Caroline

Hi,

I am running Slamm on Carpinteria Marsh near Santa Barbara. I ran it using the accretion/sed/erosion rates for Puget Sound which I would assume are much different for Carpinteria. I have searched the literature high and low but can't seem to find any rates for Carpinteria. I did find an accretion rate for Tijuana slough:  "Vertical Accretion Rates and Heavy Metal Chronologies in Weland Sediments of the Tijuana Estuary" but this area may be different that further north. I found some data for SF Bay but again that is much further north and has differerent conditions. Any ideas where I might find this info?

Thanks,

Caroline