I have problem on my model result,
first of all I'm doing a hydrodynamic model with a nested model which is planned to be made of 4 nested domains
The first domain has ran successfully, now I'm trying to run the second nested model domain
My first domain is Indonesia as a whole, and I do nesting for the second domain in the Lesser Sunda Islands
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I have struggled the n-th problems of blow up since my model area covers many narrow straits,
let's say the place where the blow up occurs is in the westernmost strait, then I overcome this by changing the bathymetry value in the strait to be deeper
then the blow up moved to another strait to the east, and I did the same thing by increasing the bathymetry value in that strait and also changing the minimum depth on the island around the strait (by default my mininum depth is 20 meters, but because of this problem I raise the minimum depth only on any land near the strait manually)
I did that for other straits (because blow ups always move to the next strait further east)
this is Lesser Sunda Islands
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after doing this over and over again, finally my model (second nested domain) can run smoothly until the end without blow up
but the problem is that the elevation value in my model decreases over time
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I have checked the elevation value of the second nested domain all over the model
I overlayed the elevation value from the 1st and 2nd domain to check the concistency because I think there is a problem when making contact between domains 1 and 2, but I found the elevation value from Domain 2 decreases all over the place except at the outermost grid at the boundary compared to elevation value from Domain 1
I ran out of idea where's the problem and how to solve this,
I really need help for this problem
I'm really looking forward to an answer that might be a solution to this problem
Thank you
Sincerely,
Theresia