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# Ocean Dynamics - Science topic

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I am looking for some quality biophysical data products (ocean temperature, salinity, dissolved oxygen, Chl-a etc.), especially in-situ ones, for the water bodies situated near the arctic sea and Antarctica. Profiling Floats, Ice-Borne Observing Systems, Ice/Snow Surface Drifters etc. are some of the systems for acquiring polar ocean datasets. So far, I have come across the following sources:
1. International Arctic Buoy Program: https://iabp.apl.uw.edu/data.html
2. USGODAE Argo GDAC Data Browser: https://nrlgodae1.nrlmry.navy.mil/cgi-bin/argo_select.pl
3. Biogeochemical-Argo: https://biogeochemical-argo.org/data-access.php
Are these sources good enough to represent ocean dynamics within the polar circle? I would much appreciate it if you could point out some other sources, whether it is in-situ, satellite or model, for understanding polar ocean dynamics.
Have a look on the Ocean Data View website, there are quite a lot of datasets available there. For temp, salinity, oxygen, nutrient and the derivatives of these variables, World Ocean Atlas (WOA13 or 18) is great. You can find that on the ODV site, and then look at it through the ODV software. Its quite easy to use, and specific data can then be extracted.
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The progressive global warming process in many ways adversely affects the ecosystems of the seas and oceans. In addition, the growing scale of pollution, waste, including plastic waste and many other toxic, non-biodegradable, contributes to adverse changes in many areas, sea zones and assessments, as well as biological depletion of biodiversity of ecosystems. The scale of this depletion is already beginning to be noticeable also for people in some areas of the sea, in which the number of fished fish is decreasing.
In addition, the rising temperature of the seas and oceans, which will be a derivative of the global warmning process, causes changes in ocean currents, which causes the appearance of new weather anomalies and climatic disasters also in land areas inhabited by people. Until recently, it was thought that seas and assessments, due to their high volume potential for land surfaces, would act as a kind of buffer factor for the global warming process. However, it turns out that the seas and oceans are unlikely to play the role of a buffer factor, they will only quickly undergo the global warmnig process and in this way may also become another factor strengthening the scale of increasingly occurring weather anomalies and climatic cataclysms.
Do you agree with me on the above matter?
In the context of the above issues, I am asking you the following question:
Are the seas assessed as a global warming process buffer or are they subject to this process?
I invite you to the discussion
The seas and oceans partially buffer the greenhouse effect. However, the increasing temperature and acidity of seawater and oceans is causing the extinction of coral reefs and many marine life. These are also very negative effects of the ongoing global warming process.
Greetings,
Dariusz Prokopowicz
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In general, there are several automated eddy detection algorithms. However, each identification method poses a multinuclear eddy identification problem, e.g., multiple SLA extremes. This problem can occur when multiple eddies are physically close together. We tried to solve this problem with the following paper "A new mononuclear eddy identification method with simple splitting strategies" and the paper "Technical Note: Watershed strategy for oceanic mesoscale eddy splitting" in Ocean Science, which can be downloaded from http://www.ocean-sci-discuss.net/11/1719/2014/osd-11-1719-2014.html. We hope these strategies be helpful for the investigations in ocean dynamics.
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Are filters the only way or it can be done by following other algorithms.
Above mentioned pl66tn function is available in https://github.com/sea-mat/bobstuff/blob/master/pl66tn.m
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I was drawing plots using ODV software, but I couldn't mask the bottom bathymetry. Can anyone tell how to mask the bottom bathymetry?
Isobaths: To highlight isobaths on a map at 100m, 500m, 1000m, 2000m, 4000m and 5000m: Go to View->Window Properties->Map->Layers, then unclick Automatic selection. You want to plot ‘Ocean Bathymetry’, then click “Compose”, highlight the isobaths (listed above in the “available” tab), then click the “<<” button and tick “draw colourbar” to see the corresponding isobaths on the map
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I know some papers reconstructed the paleo PDO by proxy data. But the time periods of PDO are usually thousands of years ago. I want to know something about the PDO in deep-time geology period.
Thank you for your kindly help and useful discussion!!!
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It is true that CO2 is soluble in water. As soon it come in contact with water molecules, it produce carbonic acid.
CO2 + H2O = H2CO3
Carbonic acid work on slightly or non soluble calcium and magnesium salt and make it soluble.
CaCO3 + HCO3 = Ca(HCO3)3
This is how alkalinity/pH is increased.
But how it increase ocean acidity. Or, this ocean acidity is a temporary phenomena?
To me, increase and decrease in oven pH is part of ocean ecology. Why it is presented is a problem?
There is a full description, by top scientists from Wood Holes Oceanographic Institution, of the problem of ocean acidification here: http://www.whoi.edu/website/OCB-OA/faqs/oa-primer
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I have modeled Persian Gulf (salinity, temperature, and currents) by using  FVCOM model. meteorological data have downloaded in ECMWF web site. The model had unstabled before 2 year Run and temperature decrease to -20 degree centigrade.
Now I know the problem is heat flux data. Can anyone help me about  "Net surface heat flux" and "Shortwave irradiation flux at the surface (w/m2)"?
1- Where can I obtain "Net surface heat flux and Shortwave irradiation flux at the surface (w/m2)"?
2- How can I change heat flux coefficient in FVCOM model?
Thanks a lot
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Water temperature has small variations near the bottom if it is deep, so it could be considered in good balance with the seabed (although in some areas there is a strong seismic activity). This is not true for a shellow shelf water and I presume there must be some heat exchange due to seasonal variations, but I am not sure if it is significant. Does anybody have some references to read about?
Thank you all! I didn't look at this page for a long time and now I found some new answers. Actually, what I meant is not a geothermal heat flux, but heat exchange between seabed and ocean waters in shallow areas, where 1) seasonal temperature variations are significant, and 2) part of solar radiation passes down to the bottom and makes it warmer.
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I am analysing a coastal time-series of hourly temperature and salinity measurements. I have calculated the density using Gibbs seawater toolbox (TEOS10). In addition I have also calculated the seawater density/stability ratio $R_{\rho}$,
$R_{\rho} = \frac{\alpha \Delta\Theta}{\beta \Delta S_A}$.
Specifically, I want to distinguish between density changes affected by either changes in temperature or salinity. So far I have just seen articles analysing the spatial distribution of the density/stability ratio, either vertical or horizontal, and mentioning that when $-1 < R_{\rho} < 1$, the density is affected mostly by changes in salinity.
Could anyone please suggest further references, especially analysing this ratio using time-series?
Cheers!
I think your interest to examine these temperature and salinity density/stability ratio on the coastline rather on the open water. If so, I suggest you look in other factors i.e., tidal chandes, local current circulation and bathymetry.
These elements are affected local dwillers in many ways i.e., induce spawning
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Hi,
I am having some problems with the space varying temperature file in FLOW module.
I have prepared a space varying temperature file for my project (part of which is shown below):
FileVersion = 1.03
Filetype = meteo_on_equidistant_grid
n_cols = 3
n_rows = 4
grid_unit = degree
x_llcenter = -9
dx = 1.5
y_llcenter = 57
dy = -1.5
NODATA_value = 999.999
n_quantity = 1
quantity1 = air_temperature
unit1 = Celsius
TIME = 0.0 hours since 2013-09-01 00:00:00 +00:00
10.255 12.162 13.800
12.161 12.614 12.984
12.931 12.974 11.971
12.995 13.184 12.951
and I am including these files in the mdf file as specified in the FLOW manual:
Commnt =
Wnsvwp = #Y#
Wndint = #Y#
Commnt =
.
.
.
Commnt =
Filwu = #ERA_Interim_092013_072014.amu#
Filwv = #ERA_Interim_092013_072014.amv#
Filwp = #ERA_Interim_092013_072014.amp#
Filwt = #ERA_Interim_092013_072014.amt#
Commnt =
However, the model doesn't run and I got the following error:
*** MESSAGE Air temperature specified on a separate equidistant grid
*** ERROR Air temperature is not used in heat model (ktemp) = 0
Can anybody please help me with this or point to some possible errors I may be making?
Hello,
I'm doing a similar application with heat model 5 (ocean) with varying meteo parameters. Can you tell me which parameters did you put in the .tem file?
Thank you!
Magda
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I am checking the biological production rate in a particular season and hence studying seasonal variability.
Dear Samiran,
2. For chlorophyll check http://oceancolor.gsfc.nasa.gov/cms/
Rgds.
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I am wondering about the data quality for the (1000-1500k Hz) Rowe RTI ADCP, how is it when comparing with the other brand?
Rowe's ADCP can provide higher output rate.
Is the data quality good using 1Hz output in a shallow water of 5 m?
Thanks,
Dear Huang,
I have used Sontek ADCP having 1MHz capacity. If we are using this ADCP for collecting current profiles in a depth of 5 m; 1Hz for data output may not be enough. In shallow water processes are complex and quick. As of my experience minimum 5Hz is required to collecting the accurate current data at 5m depth. Please take necessary action  after getting answers from more experts. All the best
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That's a rather general question and I'm not completely clear about what you had in mind by 'sea industries'.
Perhaps the obvious answer is ion removal. MD simulations are used to study various ways of separating salt from water: 1) aiming to make it drinkable, 2) selectively removing for example radioactive waste material from seawater.
I can think of some other MD simulations that are potentially interesting for seawater industries: for example simulating oil at the salt water-air interface. Would form a monolayer I'm guessing. However, I'm making this up as I go, so some literature research would be needed to see what the open questions and applications would be.
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Lower resolution CTD can miss too much of the detail maybe?
Not sure about 1KHz, but if you wanted to callibrate before casting them, controll environment is the best as Mr jf Argentino suggested. And as for more the manufacture information must be kept in mind for accuracy n resolution for those sensor.
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Charnock parameter is approximately saturated under high wind speeds.Will Charnock parameter be decreased under gale-force winds? What is the role of the wave age and sea spray on this possible decrease?
Hi Georges:
At high winds (above 25ms-1) the sea surface roughness saturates hence the Charnock coefficient becomes constant. This does not mean that for higher winds  the momentum flux becomes constant because it increases as the wind speed squared. A good reference on surface roughness saturation is the paper by Donelan et al. 2004 published in Geophys. Res. Lett. Measurements in hurricanes have shown a decrease of drag coefficient at very strong winds this topic is discussed in papers by Emanuel, Soloviev and others.
Regards
Héctor
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Recently, I was looking for a generating mechanism to explain a frontal wave evolutionary process which occured in the shear transition zone (front zone)between zhejiang coastal current and taiwan current( a branch of Kuroshio Current) observed by satelite. I used a barotroptoc model to make a linear stability analysis, the result is not good enough to match our observation.  How the time and space scale to change if I use the baroclinic model to analysis? bigger or smaller? thanks!
Thanks for the analysis，Guillermo and Enda,  it's very useful for me. after i  understand the baroclinic instability, i will try to  analyze the mechanism with it. thanks again!
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Climate change induced an increase in the surface water temperatures and salinity in various oceans and seas in the world. I need the amounts of their increase per decade in past several years. Please attach the article as references with your valuable reply.
Dear Kenneth, yes there exists an asymmetry, since we have unique 1855 western valid stations and 1136 unique eastern ones.
Summaries, for western annual averages:
Min. 1st Qu. Median Mean 3rd Qu. Max.
-17.370 6.858 10.220 10.630 14.720 31.320
Eastern annual averages:
Min. 1st Qu. Median Mean 3rd Qu. Max.
-17.240 2.383 7.358 8.134 12.810 30.800
Observe that extreme values are similar, so my Extreme Value analysis has meaning.
PS Why at Clayton's paper are there so few stations? (just 286?)
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What is the effects of seagrass beds (posidonia in Mediterranean Sea) in the nearshore zone:
-  on wave attenuation;
-  on suspended sediment transport?
How can we configure to test the effects of posidonia in a coupled hydrodynamic-sediment transport 2D (Mike 21)?
Hello,
Here you can find several paper about wave damping over Posidonia oceanica meadow:
Response of Posidonia oceanica to wave motion in shallow-waters-preliminary experimental results, L Cavallaro, C Lo Re, G Paratore, A Viviano, E Foti
Coastal Engineering Proceedings 1 (32), waves. 49
Theoharris Koftis, Panayotis Prinos, Vasiliki Stratigaki, Wave damping over artificial Posidonia oceanica meadow: A large-scale experimental study, Coastal Engineering, Volume 73, March 2013, Pages 71-83, ISSN 0378-3839, http://dx.doi.org/10.1016/j.coastaleng.2012.10.007.
Influence of Blade Flexibility on the Drag Coefficient of Aquatic Vegetation
C Houser, S Trimble, B Morales - Estuaries and Coasts, 2014 - Springer
M.E. Anderson, J.M. Smith, Wave attenuation by flexible, idealized salt marsh vegetation, Coastal Engineering, Volume 83, January 2014, Pages 82-92, ISSN 0378-3839, http://dx.doi.org/10.1016/j.coastaleng.2013.10.004.
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I am working with a modified form of Csanady's (1978) classic Arrested Topographic Wave (ATW) model. I am interested on the effects of a periodic pressure forcing at the shelf edge (like a meandering western boundary current) on the shelf circulation. Does anyone know of papers or other references where a similar form of the ATW model is used?
Probably these two also:
Higginson, S., K. R. Thompson, P. L. Woodworth, and C. W. Hughes. “The Tilt of Mean Sea Level Along the East Coast of North America.” Geophys. Res. Lett. 42, no. 5 (March 9, 2015): 1471–1479. doi:10.1002/2015gl063186.
Brink, K. H. “Buoyancy Arrest and Shelf–Ocean Exchange.” J. Phys. Oceanogr. 42, no. 4 (April 2012): 644–658. doi:10.1175/jpo-d-11-0143.1.
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We need to study more about dynamics of water temperature due to climate change and its effect on marine organisms in Indian Ocean
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I am trying to understand the energetics of coastal circulations on the west coast of India. what are the type of analysis and modelling study required?. what are the reliable temperature/salinity sources can be used as boundary conditions?.
On top of tides, winds and density, if you are referring to near-shore circulation, the effect of gravity waves through Stokes drift velocities and wave setup (water piling against the coast) can be very important... but it depends on the spatial scale, as Francesco said, and the particular characteristics of the area you are focusing on.
This is a broad research theme. I would recommend the paper by Uchiyama et al (2010) for  the wave currents interaction in the near-shore.
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Im wondering how to consider when to use a structured grid or an unstructured grid when conducting a coastal current simulation or probably even and other simulation as well. Im aware that some study suggest structured grid have higher accuracy but im wondering does the result would be affected if structured/unstructured grid is used on shallow coastal(<20 meter depth) in an enclosed bay especially.
As the prior answers suggest, it's a compromise.  Structured grids are simpler to code, so if a significant constraint is programming time, this is the way to go.  Unstructured grids allow you to place the resolution where you need it (more easily), so if computing time is the main limit, this is the way to go.
In deciding whether you're more limited by programming time or computing time, don't underestimate the programming time.  It's awfully easy to do so.  Programming time includes not just the initial getting to the point of having meaningful answers in this particular model, but in developing all the programs and scripts for the care and feeding of the model (e.g. translating forcing fields to the model's grid -- easier with structured grids), and in maintaining all of your system's codes (again, can be more complex with unstructured grids).  The maintenance, care, and feeding of a model system is about 10x the programming time of the core model in my experience.
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I need to know mainly at which rate the solar light penetration drops from the surface to the deeper sea for coastal waters. I found in the NASA website that in the open ocean at 75m depth only 10% of solar light reaches and the picture shows this percentage is almost zero at 50m depth in the coastal waters. I need to know this reduction in light penetration in coastal waters with high suspended matter load.
Dear Haimanti,
As far as I know, the evaluation of the coefficients R, D1 and D2 where obtained by Jerlov with Secchi disks (an empirical method but that works quite well). You can also find in the litterature only one exponential (by neglecting the IR radiation) or else parameterization function of chlorophyle (see for instance: Ohlmann 2003, J. Climate, 16, 1337; or Sweeney et al., 2005, JPO, 35, 1103). But for me the best performance can be obtained with the old results of Jerlov, Paulson and Simpson, or Simson and Dickey. Of course if you have PAR data this is the best to evaluate new coefficients for very specific cases.
All the best
G.C.
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MHWS=Mean High Water Spring
MLWS=Mean Low Water Spring
HAT=Highest Astronomical Tide
LAT=Lowest Astronomical Tide
John is of course right, but in practice HAT and LAT are defined by means of analysing some tide gauge data with suitable software, determining tidal constants, and then computing tidal predictions (say every minute) for 18.6 years. The highest and lowest levels are then HAT and LAT. The UKHO (in the UK case) defines Chart Datum from that estimate of LAT (i.e. a depth below MSL), usually with some rounding to a sensible number of decimal places. See for example page 10 of the Pugh and Woodworth 2014 sea level book.
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Relation between tsunami wave height and inundation?
It's very difficult evaluate the relationship of the tsunami wave increase and inundation, because it's dependent of multiple factors, e.g bathymetry, topography, resonance affects in continental platform and harbors.
To analyze this relationship is necessary model your local tsunami scenarios and propagate to the coast, to obtain an approximation of your question.
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Is the diapycnical eddy diffusivities as important as being understood in ocean general circulation, even in ocean thermohaline circulation?
The role of salt fingers in oceanic mixing has been controversial. Some researcher emphasize the smallness of the net buoyancy flux. But others think they can provide diapycnal fluxes of heat, salt and density in the ocean thermocline more efficient than the turbulence does. It is hard to choose the right parameter to apply the formulas.
Diapycnical diffusivity is mainly due to breaking of internal waves. It is essential to maintain the overturning (thermoshaline) circulation because cold water must be mixed with warm water on the upward branch. For this you need mechanical energy which comes for the wave field, converted to turbulence by breaking. I recommend my papers:
Olbers and Eden JPO 2013
Eden and Olbers JPO 2014
and my book
Olbers, Willebrand, Eden, Springer 2012.
Of there is a lot other literature, eg the nice review by MacKinnon etal 2014 (2013?) in the Oceans&Climate book, ed by Siedler etal.
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