River runoff problem
River runoff problem
Dear all
I run the model but I have faced a problem. I have 4 rivers and define monthly discharge with salinity=3 and Temperature=12.
Here is the location of river points in my grid.
As my river comes from left to right, I define river transport as positive as mentioned here https://www.myroms.org/wiki/River_Runoff.
But after running, the model in the river runoff position shows more salinity compared to other points(top-left).
I cannot understand why?
The only thing that can be the wrong i,j? or transport?
please help me with your interesting comments
I run the model but I have faced a problem. I have 4 rivers and define monthly discharge with salinity=3 and Temperature=12.
Here is the location of river points in my grid.
As my river comes from left to right, I define river transport as positive as mentioned here https://www.myroms.org/wiki/River_Runoff.
But after running, the model in the river runoff position shows more salinity compared to other points(top-left).
I cannot understand why?
The only thing that can be the wrong i,j? or transport?
please help me with your interesting comments
Re: River runoff problem
it could be i, j, or transport.
make sure the Q is positive for flow to the right.
look at the u values and ensure the rivers are coming from the correct locations.
those locations should be masked points. the river flow will overwrite the zero values at the masked locations.
-j
make sure the Q is positive for flow to the right.
look at the u values and ensure the rivers are coming from the correct locations.
those locations should be masked points. the river flow will overwrite the zero values at the masked locations.
-j
Re: River runoff problem
Hi
Thanks for your reply!
I have checked u velocity. It is here. I guess that the flow is towards the left.
The transport is positive so this can not be the problem.
With regard to i,j, I consider i=15 and j=295 in my file(for example). is it right? the result is based on this approach!
now should i define i=16 and j=295 or i=14 and j=295?
Thanks for your reply!
I have checked u velocity. It is here. I guess that the flow is towards the left.
The transport is positive so this can not be the problem.
With regard to i,j, I consider i=15 and j=295 in my file(for example). is it right? the result is based on this approach!
now should i define i=16 and j=295 or i=14 and j=295?
Re: River runoff problem
https://www.myroms.org/wiki/River_Runof ... _Eposition
is a good description of the river locations.
it needs to be coming out of the land masked cell.
is a good description of the river locations.
it needs to be coming out of the land masked cell.
- jivica
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Re: River runoff problem
A long time ago Rich Signell wrote very useful Matlab function called "map_rivers.m" (I can see you are using Matlab).
If you can't find it in the ROMS matlab repo or somewhere on the net, I will try to dig it out.
Hope this example (you are showing on the figures) is not something you want to use seriously, you need to define proper river inputs/model forcing/ grid etc...(this is the Adriatic Sea and there are publications with many studies related to ROFI and whole circulation is veeeery sensitive to all that...)
Good luck,
Ivica
If you can't find it in the ROMS matlab repo or somewhere on the net, I will try to dig it out.
Hope this example (you are showing on the figures) is not something you want to use seriously, you need to define proper river inputs/model forcing/ grid etc...(this is the Adriatic Sea and there are publications with many studies related to ROFI and whole circulation is veeeery sensitive to all that...)
Good luck,
Ivica
Re: River runoff problem
The function roms_plot_river_source_locations.m in my roms_wilkin tools https://github.com/johnwilkin/roms_wilkin will plot the sources in Matlab with symbols to indicate the flow direction.
John Wilkin: DMCS Rutgers University
71 Dudley Rd, New Brunswick, NJ 08901-8521, USA. ph: 609-630-0559 jwilkin@rutgers.edu
71 Dudley Rd, New Brunswick, NJ 08901-8521, USA. ph: 609-630-0559 jwilkin@rutgers.edu
Re: River runoff problem
Hi
Thanks!
I have a dilemma about one point.
In my case, I have 40 layers.
I should define V_shape (s_rho)from 1 to 40 or 0 to 39?
Another dilemma would be the least number would be for the bottom!
Best,
Javad
Thanks!
I have a dilemma about one point.
In my case, I have 40 layers.
I should define V_shape (s_rho)from 1 to 40 or 0 to 39?
Another dilemma would be the least number would be for the bottom!
Best,
Javad
Re: River runoff problem
river_Vshape has the properties ...
so in your case dimension s_rho = 40. But whether you count from 0 to 39 or 1 to 40 depends only on the App you are using to read/write it. To distribute the river uniformly over all depths you want river_Vshape = 1/40 (i.e. = 0.025) for all values so it satisfies the property must sum to 1 over the s_rho coordinate.
If you want to weight the source toward the surface instead of being uniform, you make the weights larger toward higher values of s_rho because s_rho = 0 is the bottom and s_rho = (here 40) is the surface.
Code: Select all
double river_Vshape(s_rho, river) ;
river_Vshape:long_name = "river runoff mass transport vertical profile" ;
river_Vshape:requires = "must sum to 1 over the s_rho coordinate" ;
If you want to weight the source toward the surface instead of being uniform, you make the weights larger toward higher values of s_rho because s_rho = 0 is the bottom and s_rho = (here 40) is the surface.
John Wilkin: DMCS Rutgers University
71 Dudley Rd, New Brunswick, NJ 08901-8521, USA. ph: 609-630-0559 jwilkin@rutgers.edu
71 Dudley Rd, New Brunswick, NJ 08901-8521, USA. ph: 609-630-0559 jwilkin@rutgers.edu
Re: River runoff problem
I try to define a profile thus I weigh in different layers. Here is it
I considered s_rho=1 to s_rho=40 is not right?
Do you mention that I should s_rho=0 to s_rho=40? It will be 41 layer?
I considered s_rho=1 to s_rho=40 is not right?
Do you mention that I should s_rho=0 to s_rho=40? It will be 41 layer?
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Re: River runoff problem
Here s_rho is just an index for the vertical dimension. You say you have 40 vertical layers, i.e. you have N = 40 in ROMS. If you are working in Python then the index is from 0 to 39, if you are in Matlab the index is from 1 to 40.
That plot is an oddly varying profile for river_Vshape. You do understand what river_Vshape does, right? It partitions the inflow river_transport into the vertical cells. This doesn't have a huge impact on the solution because ocean dynamics quickly adjust the profile.
That plot is an oddly varying profile for river_Vshape. You do understand what river_Vshape does, right? It partitions the inflow river_transport into the vertical cells. This doesn't have a huge impact on the solution because ocean dynamics quickly adjust the profile.
John Wilkin: DMCS Rutgers University
71 Dudley Rd, New Brunswick, NJ 08901-8521, USA. ph: 609-630-0559 jwilkin@rutgers.edu
71 Dudley Rd, New Brunswick, NJ 08901-8521, USA. ph: 609-630-0559 jwilkin@rutgers.edu