The DEM must have some vertical datum to which elevations are referenced -- are the elevations in terms of the 1974 datum?
The MTL-NAVD88 parameter is set up such that if you looked at a gauge and there was a referenced MTL height and a referenced NAVD88 height, the value would be the difference of the two numbers referenced.
The 64-bit version of the software should be able to accommodate nearly any map size -- the limitations are the memory of the machine (and there are also practical limitations in terms of how long it takes to load and run simulations.) We have found the maximum size that is reasonably practicable to run is approximately 26 GB of memory (~250 million cells) but that obviously requires 32 GB of memory or more.
Note the memory utilization in GB is given in the SLAMM File setup window and different optimization options are available a the bottom of the screen.
e.g. "Cells to Track 7,169,539, memory utilization in GB 0.7478"
Are you saying that data can be input at 10m resolution in 6.0.1 but that 6.7 crashes with the same data set? Have you tried converting the data to binary using the binary button? This significantly optimizes input/output and may shed light on the problem. If you cannot solve the problem, you can send me the data files and I can look at it, but I'm afraid I have not been very responsive in terms of loading other people's data lately. Sorry that the software is not giving you a more helpful error message.
Last post by andybell - September 17, 2019, 04:01:03 PM
Hi, I have just installed SLAMM 6.7 on my laptop (8GB Ramm on windows 10) I am trying to run a model that I have downscaled from 2m to 10m resolution, but get an error when it reaches 6% in reading the site characteristics. The error reads "Invalid Floating Point Operation". The error comes up when the 6% progress is met
Any clues what might cause this? Many thanks in advance
1. "ASTER DEM standard data products are produced with 30m postings, and have Z accuracies generally between 10 m and 25 m root mean square error (RMSE)." I'm afraid that that Z accuracy is not going to be compatible with modeling the effects of 1-2 meters of SLR on marsh systems. You will need LiDAR or ifSar. I would say you wouldn't want a vertical RMSE of above 25 cm.
2. In US applications we get MHHW and MLLW data from NOAA gauges. You can use whichever type of tide gauge or water level monitoring data that you have available -- long term data are best.
3. The SLAMM model usually assumes that tidal flats have a lowest elevation at MLLW. That means that you would need aerial imagery that is tidally coordinated (taken at low tide)
i got 2 queries, 1. how to produce NWI data ( i was looking for a more clear answer as i am not that expert in GIS)? 2. If I use ASTER GDEM data other than LiDAR, will I face any problem with my result?