Search found 22 matches

by chysun
Wed Jun 14, 2017 4:27 pm
Forum: ROMS Discussion
Topic: Some questions about water transport at OBC
Replies: 3
Views: 2111

Re: Some questions about water transport at OBC

Hi Kate, Thanks for your comments! Forgive me for not having knowledge of ROMS lingo. I get those doubts when I try to figure out why ROMS tidal elevation is about 20% below the insitu data in my tidal case. Some parameters like surface/bottom roughness, drag coefficient, may relate to my problem ...
by chysun
Sun Jun 11, 2017 3:56 am
Forum: ROMS Discussion
Topic: Some questions about water transport at OBC
Replies: 3
Views: 2111

Some questions about water transport at OBC

Hi all, I have some doubts about water transport at OBC when imposing tides. Hopes I can get some tips here. 1.Does topography cut off contribute the inaccuracy of water transport especially at OBC which water goes in and out and how do we deal with it if it does? ROMS needs a topography cut off to ...
by chysun
Sun Jun 11, 2017 2:03 am
Forum: ROMS Discussion
Topic: Inconsistent results after updating for the option SPLINES
Replies: 2
Views: 1982

Re: Inconsistent results after updating for the option SPLIN

Hi Kate, Well, the figures above are exactly from the versions before and after SPLINES changes. I carefully read and compare ROMS codes of these two versions just to find all "SPLINES" cpp options are splited and replaced by "SPLINES_*" in the new version, while the algorithm remains the same. I've ...
by chysun
Tue May 30, 2017 8:42 am
Forum: ROMS Discussion
Topic: Inconsistent results after updating for the option SPLINES
Replies: 2
Views: 1982

Inconsistent results after updating for the option SPLINES

Hi all, I recently updated my ROMS repositories from revision 761 (Sat, 28 Mar 2015) to revision 838 (Sat, 04 Mar 2017) then I got inconsistent results between these two revisions which has confused me for a while.Hopes I can get some tips here. Attached are 2 monthly averaged plots of two revisions ...
by chysun
Thu Jan 19, 2017 4:50 pm
Forum: ROMS Discussion
Topic: Biological tracers coupling with currents
Replies: 2
Views: 2794

Re: Biological tracers coupling with currents

Hi Katja,

Thanks for quick reply.
Your might be probably right,a nudging zone for NO3 variable plus a sponge zone for flows can be one way that helps with my boundary problems. I'll try it.

Best, Haiyun
by chysun
Wed Jan 18, 2017 2:31 am
Forum: ROMS Discussion
Topic: Biological tracers coupling with currents
Replies: 2
Views: 2794

Biological tracers coupling with currents

Hi, I'm running ROMS coupling with an biological model(bio_Fennel.in) and meet some boundary problems which puzzled me for quite some time now.Hope I can get some help here. The model domain is 1S~35N,99E~140E with resolution about 7km. HYCOM reanalysis is provided as hydrodynamic initial&boundary ...
by chysun
Sun Jan 15, 2017 6:58 am
Forum: ROMS Discussion
Topic: Tidal forcing on 3D momentum boundary field
Replies: 2
Views: 2444

Re: Tidal forcing on 3D momentum boundary field

Dear Kate,
Thanks for your reply.
I got the answer from ROMS codes about time stepping 2d&3d momentum equations(step2d_LE_AM3.F step3d_uv.F) as you noticed.
by chysun
Tue Jan 10, 2017 5:38 pm
Forum: ROMS Discussion
Topic: Tidal forcing on 3D momentum boundary field
Replies: 2
Views: 2444

Tidal forcing on 3D momentum boundary field

Hi, I try to figure out how tides is put into ROMS boundary. Following what wikiroms says there are three ways to include tides: 1.You can specify a time-dependent boundary condition file that temporally resolves the tides and skip the tides file entirely. 2.You can specify SSH_TIDES and/or UV_TIDES ...
by chysun
Tue Oct 18, 2016 3:25 pm
Forum: ROMS Problems
Topic: Unrealisitic thickness of mixed layer
Replies: 15
Views: 22623

Re: Unrealisitic thickness of mixed layer

Hi, Good news on our issue! We check the tides at shore and found it unreasonably strong which might cause strong diffusion of thermocline at slope . The temp profile and time series make progress when we don't impose tide. I guess we haven't set our tides correctly.We will double check our tide ...
by chysun
Sun Oct 09, 2016 2:27 am
Forum: ROMS Discussion
Topic: Wind affects little to surface currents
Replies: 1
Views: 2311

Re: Wind affects little to surface currents

updates: For wind-current plot I correct my time index to 00Z corresponding to HYCOM time coordinate.Then I can see wind effect at the surface but somehow it didn't simulate the eddy well. There must be something I should have taken care to improve my result (like diffusion coefficient for tracers ...
by chysun
Fri Sep 30, 2016 8:21 am
Forum: ROMS Discussion
Topic: Wind affects little to surface currents
Replies: 1
Views: 2311

Wind affects little to surface currents

Hi, I'm doing an SCS(Southern China Sea) test case using ROMS,but I find my surface current field has little response to the wind field even there is a large scale cyclone. Wind forcing is from ERA_ITERIM 10m wind with BLK_ZW set to 10 and bulk_flux defined . I'm sure ROMS reads the wind because ...
by chysun
Thu Sep 29, 2016 2:21 am
Forum: ROMS Discussion
Topic: Parallelization and tiling
Replies: 6
Views: 5796

Re: Parallelization and tiling

Hi kate,
Thanks for your reminder.I will read it carefully.
by chysun
Thu Sep 29, 2016 2:19 am
Forum: ROMS Discussion
Topic: Quetions about solar radiation as ROMS input forcing
Replies: 7
Views: 7326

Re: Quetions about solar radiation as ROMS input forcing

Hi John and Kate,
Follow your ideas I get a better understanding of the procedure of air-sea interchange.I'm not using sea ice model but I will take care when I deal with it in the future.
Thanks for your opinions!
by chysun
Wed Sep 28, 2016 7:31 am
Forum: ROMS Discussion
Topic: Parallelization and tiling
Replies: 6
Views: 5796

Re: Parallelization and tiling

Hi, I am recently reading ROMS code and try to export some of its intermediate variable,but most fields are tiled because ROMS has a parallel computing method. I can see there is a routine that collect tiled array in Utility/distribute.F but I still cannot handle it.is there anyone who has ...
by chysun
Wed Sep 28, 2016 3:36 am
Forum: ROMS Discussion
Topic: Quetions about solar radiation as ROMS input forcing
Replies: 7
Views: 7326

Quetions about solar radiation as ROMS input forcing

Hi,
I'm a little confused weather I should use net solar radiation or downward solar radiation as ROMS input forcing.Could anyone tell me which one is correct and why should we use it ?

Thanks advance.
Haiyun
by chysun
Tue Sep 13, 2016 8:27 am
Forum: ROMS Problems
Topic: Temperature Difference from ROMS to HYCOM
Replies: 9
Views: 13763

Re: Temperature Difference from ROMS to HYCOM

Hi Rodrigo, Thank you for sharing experience about pge test.I get a better understanding of pge and its influence factor. :wink: Now rx0 is limited to not more than 0.1 and I do the pge test following your idea (sponge,nonlinear temp profile,zero u,v,zeta,etc) The pge test shows improvement compared ...
by chysun
Sat Aug 27, 2016 9:09 am
Forum: ROMS Problems
Topic: Temperature Difference from ROMS to HYCOM
Replies: 9
Views: 13763

Re: Temperature Difference from ROMS to HYCOM

Hi rduran, Thank you for your reply.I make a gif of daily averaged velocity at bottom. The currents are developing all the time and they are obviously too strong.Yes I can see negative vorticity regions along the section line which cause upwelling,your notice is helpful! I think the bottom velocity d ...
by chysun
Fri Aug 26, 2016 1:30 am
Forum: ROMS Problems
Topic: Temperature Difference from ROMS to HYCOM
Replies: 9
Views: 13763

Re: Temperature Difference from ROMS to HYCOM

Two days ago I smoothed the topography then I did a PGE test with no forcing and made some simple cross-section figure to check if there is any false upwelling along the slope. See attachments: There is w velocity cross-section figure with its unit m/day at day30.The figure shows a strong upwelling ...
by chysun
Mon Aug 22, 2016 10:22 am
Forum: ROMS Problems
Topic: Temperature Difference from ROMS to HYCOM
Replies: 9
Views: 13763

Re: Temperature Difference from ROMS to HYCOM

Hi, I checked Haney number (rx1) field and found it coincide with slopes where upwelling current appeared.I think my rx1 field has a close relationship to the fake upwelling current,but neither clear how HPGE leads to upwelling nor know how to decrease rx1 factor directly. Has anyone experienced ...
by chysun
Thu Aug 18, 2016 2:15 am
Forum: ROMS Problems
Topic: Temperature Difference from ROMS to HYCOM
Replies: 9
Views: 13763

Temperature Difference from ROMS to HYCOM

Hi, I have a south china sea(SCS) modelling case using HYCOM data for ROMS initial field and boundary field.My temp field has a difference from HYCOM. Configurations The domain is 95~134E and 1~35N and we have spatial varying horizontal resolution from 10km to 5km.For vertical parameterization we t ...
by chysun
Mon Jul 18, 2016 4:46 pm
Forum: ROMS Problems
Topic: Unrealisitic thickness of mixed layer
Replies: 15
Views: 22623

Re: Unrealisitic thickness of mixed layer

Hi there, I increase vertical level number from 30 to 40 and take k-kl parameters for GLS mixing instead folowing Javier's idea.Attachment shows that MLD changes little which indcates the problem relates to somthing else.I am gonna compare my forcing field with HYCOM forcing field if there is much ...
by chysun
Tue Jul 12, 2016 1:43 am
Forum: ROMS Problems
Topic: Unrealisitic thickness of mixed layer
Replies: 15
Views: 22623

Re: Unrealisitic thickness of mixed layer

I am writing to respond Javier that the MLD in your temperature profile looks better than Yong Chen's. Yong Chen and I will do the test following your idea.Thanks!