Search found 45 matches

by LiuZHQ
Fri Mar 20, 2020 8:47 am
Forum: Job Opportunities
Topic: Postdoc positions in Department of Ocean Science and Engineering, Southern University of Science and Technology
Replies: 0
Views: 491

Postdoc positions in Department of Ocean Science and Engineering, Southern University of Science and Technology

Postdoc positions in Department of Ocean Science and Engineering, Southern University of Science and Technology Job Description The Southern University of Science and Technology has several immediate postdoc openings in coastal and shelf circulation modeling. We seek highly motivated postdoctoral re...
by LiuZHQ
Mon Jan 21, 2019 9:34 am
Forum: Job Opportunities
Topic: Postdoc in Southern University of Science and Technology
Replies: 0
Views: 678

Postdoc in Southern University of Science and Technology

Job Description The Southern University of Science and Technology (SUSTC) has an immediate postdoc opening in coastal and shelf circulation modeling. We seek highly motivated postdoctoral researchers to join our ocean modeling team in the Department of Ocean Science and Engineering in Shenzhen (next...
by LiuZHQ
Sat Sep 06, 2014 6:03 am
Forum: ROMS Discussion
Topic: Analytical Tide defined in O.B.C. in COAWSTv3.1
Replies: 22
Views: 5105

Re: Analytical Tide defined in O.B.C. in COAWSTv3.1

Wondering what version of ROMS you're using. You defined the OBC for three-dimensional velocity as Red, which supposedly represented a reduced-physics OBC. I checked the ROMS code (Version 645 2013-01-22 23:21:54Z), and didn't find that option. If the actual OBC is a closed one, due to, possibly, wr...
by LiuZHQ
Sat Aug 03, 2013 7:58 am
Forum: ROMS Discussion
Topic: problems in ROMS tide simulation
Replies: 14
Views: 6303

Re: problems in ROMS tide simulation

looks like you're adapting Flahter and Chapman to simulate the tidal current. To me, it is important that we provide tidal current (suggested by Kate) to this sort of OBC in Flather form (an "active" OBC in fact) to include both the tidal current and the tidal wave correctly. Or, if you insist, use ...
by LiuZHQ
Sun Jun 02, 2013 2:43 am
Forum: ROMS Problems
Topic: Error when changing boundaries for an idealized river plume
Replies: 5
Views: 2699

Re: Error when changing boundaries for an idealized river pl

I mean, you may want to increase the length of your domain to the south by adapting more grids. So that, the southern boundary will be far away from the river mouth to prevent that contaminantion from Periodic OBCs.

regards,
ZQ
by LiuZHQ
Fri May 31, 2013 3:56 am
Forum: ROMS Problems
Topic: Error when changing boundaries for an idealized river plume
Replies: 5
Views: 2699

Re: Error when changing boundaries for an idealized river pl

Since the plume propogates very fast along the coastline, and it can easily reach the southern boundary in several days. Perodic OBC brings the plume into your domain through northern boundary, which contaminant your solution. That's why I suggest you extend the domain to the south.

Regards,
ZQ
by LiuZHQ
Fri May 31, 2013 1:40 am
Forum: ROMS Problems
Topic: Error when changing boundaries for an idealized river plume
Replies: 5
Views: 2699

Re: Error when changing boundaries for an idealized river pl

I think, that periodic OBC for southern and northern boundaries should be better than the others. You may want to extend your grid southward.

Regards,
ZQ
by LiuZHQ
Sat Apr 27, 2013 9:49 am
Forum: ROMS Discussion
Topic: What to do to keep my ROMS case from blowing up??
Replies: 17
Views: 3989

Re: What to do to keep my ROMS case from blowing up??

Hi liuy, Looks like you want to hide those corners with extremely large orthogonality error in the land points, but even though, the orthogonality error in the areas you interested in is still too large (~5 degree) to be acceptable. I suggest you start from a linear grid with gradually relaxiation o...
by LiuZHQ
Sat Apr 27, 2013 4:04 am
Forum: ROMS Discussion
Topic: What to do to keep my ROMS case from blowing up??
Replies: 17
Views: 3989

Re: What to do to keep my ROMS case from blowing up??

Hi there, Yes, everyone gets the liberty to organize their own study, and I'm not trying to offense you personally. In fact, although it may take a lot of effort to generate this grid, I'm not quite sure about the orthogonality, which is critically essential as one of the basic law of ROMS. You sque...
by LiuZHQ
Wed Apr 24, 2013 3:43 pm
Forum: ROMS Discussion
Topic: What to do to keep my ROMS case from blowing up??
Replies: 17
Views: 3989

Re: What to do to keep my ROMS case from blowing up??

It is not related to the grid resolution. To be frank, this grid againsted the basic law of ROMS, and it was wrong! Before you run the model, I suggest you find a book (e.g. Dale's book) or read the user manual provided by the wikiROMS, instead of taking the model as a black box and throw all those ...
by LiuZHQ
Tue Apr 23, 2013 3:46 pm
Forum: ROMS Discussion
Topic: What to do to keep my ROMS case from blowing up??
Replies: 17
Views: 3989

Re: What to do to keep my ROMS case from blowing up??

Hi there,
kind of strange in your OBC configuration, why did you adapt chapman to zeta, Flather to the barotrophical part, closed for baroclinic part and clamped for T and S? this is totally controdiction.

Is there any reason? Or what kind of fluid you want to simulate?

regrads,
ZQ
by LiuZHQ
Sat Apr 20, 2013 3:11 am
Forum: ROMS Discussion
Topic: Need help regarding free surface in South China Sea
Replies: 4
Views: 1636

Re: Need help regarding free surface in South China Sea

Hi often, How about you compare the solutions of zeta_east, zeta_south,zeta_north in your boundary file with SODA? it there big difference? I think you included the tidal forcing in your case. Did the model you want to nest with included tide also? Or, according to your description, you nested with ...
by LiuZHQ
Fri Apr 12, 2013 2:04 am
Forum: ROMS Discussion
Topic: Problem with the river discharge
Replies: 6
Views: 2303

Re: Problem with the river discharge

Branching of the KC to Tsushima Strait is, nowadays, one of the major scientific questions related to interactions between the ECS shelves and the KC. It is not easy to answer that question: why Tsushima Warm Current and Taiwan Warm Current getting smaller during your modelling time. The way I will ...
by LiuZHQ
Fri Mar 29, 2013 2:36 am
Forum: ROMS Discussion
Topic: Question about the Results of UPWELLING
Replies: 7
Views: 2088

Re: Question about the Results of UPWELLING

Hi Zhao,
You can not expect that vertical temperature profile to be similar with the one illustrated in the WikiROMS, since you didn't plot it in the right way.

You should use h.*s_rho in MATLAB to find out the yaxis in the figure you demonstrated.

Good Luck
by LiuZHQ
Sat Jan 12, 2013 4:48 am
Forum: ROMS Discussion
Topic: What to correct to keep ROMS from blowing up?
Replies: 23
Views: 9407

Re: What to correct to keep ROMS from blowing up?

Hi there,
How about you initate the model run from rest?
by LiuZHQ
Thu Dec 27, 2012 12:55 pm
Forum: ROMS Problems
Topic: Why the gradient of temperature/salt is too large
Replies: 11
Views: 4204

Re: Why the gradient of temperature/salt is too large

Well, it's tricky to get the proper boundary solution. You can not use WOA as boundary forcing since it can definitely not resolve the find structure of the plume. Even worse, it is affected by many factors, not only the forcing you're considering here. Looks like you want to do some generalized stu...
by LiuZHQ
Tue Dec 25, 2012 3:25 am
Forum: ROMS Problems
Topic: Why the gradient of temperature/salt is too large
Replies: 11
Views: 4204

Re: Why the gradient of temperature/salt is too large

It looks like an OBC-related problem. Two suggestions: 1 (most likely). I noticed that you included the plume from PRE, and it looks like during the winter time. Frehser and colder plume arrives the open boundary and since you adapt M3RADIATION without nudging. Disturbances are reflected back into y...
by LiuZHQ
Mon Dec 24, 2012 1:33 am
Forum: ROMS Information
Topic: about conservation of roms
Replies: 5
Views: 3637

Re: about conservation of roms

That *_VOLCON options do nothing to your problem here, because it only conserves the inward and outward volume transport at the open boundaries. That non-conserved estuary circulation looks strange, and I never see that kind of problem in my idealized estuary cases with buoyancy forcing only. I sugg...
by LiuZHQ
Wed Oct 10, 2012 1:38 am
Forum: ROMS Problems
Topic: OTPS tides for ROMS
Replies: 1
Views: 1078

Re: OTPS tides for ROMS

Hi Qianfang,
Please refer to this:
https://www.myroms.org/wiki/index.php/Tidal_Forcing
for more information.

In fact, if you download the data that contains the Harmonic Constants and the software from OTIS, you will find those files and know how to generate the tidal forcing.

happy modelling
by LiuZHQ
Wed Sep 19, 2012 3:55 am
Forum: ROMS Bugs
Topic: negative temperature
Replies: 14
Views: 4503

Re: negative temperature

Hi Shou, According to the figure and question "xiaozhu557" posted here. The so called "over-heated" coastal waters are his/her major concern. Yes, the waters are warmer here. But, the temperature is still in reasonable range, and this implies that the wrong thing is not that strongly related to the ...
by LiuZHQ
Mon Sep 17, 2012 3:17 am
Forum: ROMS Bugs
Topic: negative temperature
Replies: 14
Views: 4503

Re: negative temperature

Hi there, I don't think that over-heated temperature in Bohai Sea during the summertime is because of any possible problem in ROMS itself, and the wrong thing is your configuration of the model and forcing you adapted in this domain. Please re-review the related papers and you'll find the solution. ...
by LiuZHQ
Sat Sep 15, 2012 3:53 am
Forum: ROMS Tools and Techniques
Topic: how to use seagrid to Locally Add Mesh Density
Replies: 7
Views: 2975

Re: how to use seagrid to Locally Add Mesh Density

Hi vviocean,

you may want to try Delft3D to generate the grid. Someone posted that topic.
by LiuZHQ
Fri Aug 31, 2012 1:45 am
Forum: ROMS Discussion
Topic: boundary problem
Replies: 2
Views: 1633

Re: boundary problem

please also post your configure file to help..
by LiuZHQ
Sat Aug 25, 2012 3:01 am
Forum: ROMS Installation
Topic: Blowing up problem
Replies: 5
Views: 3371

Re: Blowing up problem

Did you smooth your bathymetry?
by LiuZHQ
Sat Jul 07, 2012 7:29 am
Forum: ROMS Discussion
Topic: One question about Tidal Forcing
Replies: 2
Views: 1646

Re: One question about Tidal Forcing

Was these figures illustrating your model results or just the forcing?

Did you also include the other forcings? wind, river, or remote forcing from the major currents? Kuroshio, NEC etc...

what is your horizontal mixing algorithm? harmonic or biharmonic, what is the coefficient?

ZQ
by LiuZHQ
Wed Jun 27, 2012 1:52 am
Forum: ROMS Discussion
Topic: pressure gradient in the diagnostic output
Replies: 4
Views: 2813

Re: pressure gradient in the diagnostic output

How about just calculate the barotropic PGF from the standard zeta output? I think it is better than changing the ROMS codes.
you can get baroclinic PGF by subtracting barotropic PGF from total PGF.
by LiuZHQ
Sun Dec 25, 2011 2:42 am
Forum: ROMS Discussion
Topic: on the code of ROMS
Replies: 5
Views: 1651

Re: on the code of ROMS

there is a free software call "VisualSVN", which can be utilized to download the source code under windows OS.
by LiuZHQ
Sun Nov 13, 2011 3:23 am
Forum: ROMS Discussion
Topic: Confusion about Nudging Coefficient
Replies: 16
Views: 6520

Re: Confusion about Nudging Coefficient

looks like the OBC didn't handle the coastal trapped waves well.
Since you seleted Flather, did you also include tidal forcing in your application?
by LiuZHQ
Thu Sep 08, 2011 7:13 am
Forum: ROMS Tools and Techniques
Topic: Is there any tools to output the "dia" at the time of "his"
Replies: 7
Views: 4357

Re: Is there any tools to output the "dia" at the time of "h

leonjld, thanks for your suggestion, and I'll check it.
by LiuZHQ
Thu Sep 08, 2011 1:59 am
Forum: ROMS Tools and Techniques
Topic: Is there any tools to output the "dia" at the time of "his"
Replies: 7
Views: 4357

Re: Is there any tools to output the "dia" at the time of "h

leonjld and kate, thanks for your reply. kate was right, and to me, it looks better if we can find some method to output it directly from the model. His file can not give us the information related to time, which means we can not obtain the terms expressed as parcial something parcial time. I'd bett...
by LiuZHQ
Wed Sep 07, 2011 2:03 am
Forum: ROMS Tools and Techniques
Topic: Is there any tools to output the "dia" at the time of "his"
Replies: 7
Views: 4357

Re: Is there any tools to output the "dia" at the time of "h

Well, the diagnostic terms involve a time-integral like the averages files. I usually recommend to have NAVG=NDIA to facilitate computing budgets and fluxes. The history fields are instantaneous :!: Therefore, the time assigned to the time-averaged fields is always at the middle of the time-average...
by LiuZHQ
Mon Sep 05, 2011 10:17 am
Forum: ROMS Tools and Techniques
Topic: Is there any tools to output the "dia" at the time of "his"
Replies: 7
Views: 4357

Is there any tools to output the "dia" at the time of "his"

Dear All, I noticed that the standard momentum terms output file or the "dia" file is following the type of "avg", which is averaged during the time we defined. My question is, can we also obtain the terms at a specific time, say the time of "his" for example? Or is there any toolbox which can calcu...
by LiuZHQ
Tue May 03, 2011 1:06 pm
Forum: ROMS Tools and Techniques
Topic: How to output the boundary energy flux?
Replies: 1
Views: 1254

Re: How to output the boundary energy flux?

I wrote one program by myself to calculate the energy flux from velocity and elevation fields.
anyway, thanks for your attention all the same.
ZQ
by LiuZHQ
Mon May 02, 2011 9:03 am
Forum: ROMS Tools and Techniques
Topic: How to output the boundary energy flux?
Replies: 1
Views: 1254

How to output the boundary energy flux?

Dear all,
Is it possible to also output the energy flux crossing the OBCs into the standard "his" files? I didn't find any related options in the "in" files, and the version I'm using is ROMS 3.4.

Thanks,
ZQ
by LiuZHQ
Tue Apr 05, 2011 3:11 am
Forum: ROMS Discussion
Topic: vertical mixing & noise in a channel flow
Replies: 11
Views: 3085

Re: vertical mixing & noise in a channel flow

I follow the question of Hetland, "what is your OBC?". EW_PERIODIC?
How about also try f plane, instead of beta plane?
by LiuZHQ
Wed Mar 16, 2011 6:05 am
Forum: ROMS Bugs
Topic: Minus sediment concentration in river sediment case
Replies: 52
Views: 16017

Re: Minus sediment concentration in river sediment case

Hi Bian,
I want to remind you that the grid num. of ROMS should be started from 0, instead of 1 you read in the matlab maxtrix (Array Editor), which means you may already put the river correctly this time, even it looks like on the "land".
regards,
ZQ
by LiuZHQ
Tue Mar 15, 2011 4:15 am
Forum: ROMS Bugs
Topic: Minus sediment concentration in river sediment case
Replies: 52
Views: 16017

Re: Minus sediment concentration in river sediment case

Hi Bian, From my point of view, the abnormal "salinity" problem is also largely related to the grid or the land-sea mask at the river points. Plz also try to modify your "mask" and make the river more "smooth" or you may want to further dig the river land-ward straightly, and artificially give more ...
by LiuZHQ
Mon Mar 07, 2011 9:37 am
Forum: ROMS Problems
Topic: How to force the model after QuickScat?
Replies: 2
Views: 1578

How to force the model after QuickScat?

Dear All, I'm doing some direct simulations of the circulations in western north Pacific Ocean using ROMS. After QuickSCAT retired, I can not find a very good wind speed/stress data to force my domain except some meteorologic model results, and some of my meteorology colleagues suggested the remote ...
by LiuZHQ
Wed Jan 26, 2011 12:16 pm
Forum: ROMS Problems
Topic: Vertical Viscosity (AKv) result is strange
Replies: 5
Views: 2078

Re: Vertical Viscosity (AKv) result is strange

Bian, plz also chang the "sustr:scale_factor = 0.0005 ;" and "svstr:scale_factor = 0.0005 ;" to "sustr:scale_factor = 1 ;" and "svstr:scale_factor = 1 ;" respectively, "svstr:units = "Newton meter-2 * 1000" ;" to "svstr:units = "Newton meter-2" ;" and then generate the new wind forcing files. good l...
by LiuZHQ
Wed Jan 26, 2011 3:43 am
Forum: ROMS Problems
Topic: Vertical Viscosity (AKv) result is strange
Replies: 5
Views: 2078

Re: Vertical Viscosity (AKv) result is strange

Hi Bian, I remind you to recheck the "frc_uvstress.cdl" file before generating the forcing netcdf files. I noticed that there is some defination say "svstr:units = "Newton meter-2 * 1000;" in this file, which indicates that you should time the svstr with 1000 after converting from the wind speed V, ...
by LiuZHQ
Tue Nov 16, 2010 7:31 am
Forum: ROMS Discussion
Topic: About output the variables "lon_rho" to the "his" and"avg" ?
Replies: 6
Views: 1468

Re: About output the variables "lon_rho" to the "his" and"avg" ?

Hi kate,
you are right, I forgot to difine it in the grid file
now, the "lon_rho" appeared.
thanks very much
by LiuZHQ
Mon Nov 15, 2010 1:39 pm
Forum: ROMS Discussion
Topic: About output the variables "lon_rho" to the "his" and"avg" ?
Replies: 6
Views: 1468

Re: About output the variables "lon_rho" to the "his" and"avg" ?

Did you tell it you have a "spherical" grid? If spherical is false, it assumes you are on a flat idealized x,y plane. How did you provide the grid in the first place? Hi kate, I tried the including/excluding "spherical" from ".h" file cases and there are still not "lon_rho" in the out files. I also...
by LiuZHQ
Mon Nov 15, 2010 3:49 am
Forum: ROMS Discussion
Topic: About output the variables "lon_rho" to the "his" and"avg" ?
Replies: 6
Views: 1468

Re: About output the variables "lon_rho" to the "his" and"avg" ?

They will be there in your output netcdf files, unless you define 'NO_WRITE_GRID' in your CPP configuration file. Hi feroda, thanks for your reply, I re-checked the "avg" and "his" files and found only the "x_rho" and "y_rho" instead of "lon_rho" and "lat_rho" which I needed, and I didn't define th...
by LiuZHQ
Sun Nov 14, 2010 1:13 pm
Forum: ROMS Discussion
Topic: About output the variables "lon_rho" to the "his" and"avg" ?
Replies: 6
Views: 1468

About output the variables "lon_rho" to the "his" and"avg" ?

Hi all,
Is there any swith cotrolling outputing the variables "lon_rho", "lat_rho" to every standard output "nc" files, or the "his" and "avg" files?
Thanks and any suggestion will be welcomed.
by LiuZHQ
Tue Mar 02, 2010 2:37 pm
Forum: ROMS Installation
Topic: ROMS whit SWAN problem
Replies: 12
Views: 7652

Re: ROMS whit SWAN problem

I got the same problem say "*** glibc detected *** ./oceanM: free(): invalid next size (normal): 0x00000000352ae2f0 ***
"
and I skip the new version of ROMS and back to the ROMS148, and the problem disappeared. This is a possible solution before anyone find out the real reason.