SLAMM Forum

General Category => Model Formulation & Parameters => Topic started by: Elena V on December 09, 2012, 09:14:15 PM

Title: ocean beach erosion
Post by: Elena V on December 09, 2012, 09:14:15 PM
1. In version 6.1 beta, is there a way to specify an erosion rate for ocean beach? As I mentioned in another thread, the Bruun rule was over-predicting beach erosion, so I have stopped using it. I have done fairly extensive shoreline change analysis for my study area in southern CA, and I would like to incorporate those values into SLAMM. It would be ideal if there was another parameter called "Ocean Beach Erosion" that let me put in the erosion rates I've calculated using historic shorelines.

2. If the Bruun rule is turned off, is there any default erosion occurring for ocean beach? Or is the change I'm seeing solely due to sea level encroaching on the beach?

I see that there's a Beach Sed Rate, which I guess I could use to counter erosion in areas that are accreting by assuming a representative beach geometry in each subsite...

Thanks!
Elena
Title: Re: ocean beach erosion
Post by: Jonathan S. Clough on December 10, 2012, 07:20:57 AM
The ocean beach model could use some additional work as it is quite simple

Here's an excerpt from the latest (soon to be released) tech doc:

Elevations are adjusted for sea level rise using equation (9).  Accretion is added according to the beach sedimentation rate parameter.  If the Bruun rule is not utilized then the "T. Flat Erosion" parameter is utilized to calculate horizontal beach erosion given adequate maximum fetch (9 km).  Ocean beach is also subject to inundation to open ocean using MLLW as the default lower elevation boundary.