Ocean currents

[whipper_snapper]

I'm looking for a tool to give details of ocean surface currents. I'm sure the data is out there and available for accurate prediction over reasonable timescales of the location, direction, speed of currents, but I cannot find it with the resolution I would like. I'm thinking particularly about the Indian Ocean coastal currents which are strongly influenced by wind and have quite tight boundaries.

Thanks

 

[sarabande]

NOAA have a range of buoys

http://www.noaanews.noaa.gov/stories2009/20090504_indianoceanbuoys.html


Not sure where the data stream has gone through. I'll ferret around.


EDIT

Some sources here.

http://www.aoml.noaa.gov/phod/dac/dacdata.php


Are you after local wind-induced currents in contrast with the more permanent, predictable, ones ?


EDIT2

No 12 might be useful
http://www.nrbdrdo.res.in/ocean_projects.html


EDIT3
more data from various arrays

http://dods.ndbc.noaa.gov/oceansites/

 

[Ric]

I'm looking for a tool to give details of ocean surface currents. I'm sure the data is out there and available for accurate prediction over reasonable timescales of the location, direction, speed of currents, but I cannot find it with the resolution I would like. I'm thinking particularly about the Indian Ocean coastal currents which are strongly influenced by wind and have quite tight boundaries.

Thanks

Predictwind professional subscription has this option - but price is high.

 

[PabloPicasso]

Is https://www.windyty.com any good for you? Ah no, that's wind not currents

 

[LadyInBed]

Start here http://www.oco.noaa.gov/seaSurfaceCurrentsProduct.html
Also, in their downloads are a set of statistical ocean wind and currents charts for each month through the year.
Ed: found them here:
http://msi.nga.mil/NGAPortal/MSI.portal?_nfpb=true&_st=&_pageLabel=msi_portal_page_62&pubCode=0003

 

[FWB]

This one of Ocean currents
http://earth.nullschool.net/#current/ocean/surface/currents/orthographic=-4.10,46.14,496
compliments the wind one
http://earth.nullschool.net

 

[Pye_End]

This one of Ocean currents
http://earth.nullschool.net/#current/ocean/surface/currents/orthographic=-4.10,46.14,496

Interesting site. I wonder how they get to that level of detail - ie how accurate are all of those eddies in the Atlantic, and how much do they change.

 

[sarabande]

an intriguing site, indeed. Lots of satellite data regarding significant wave height and direction, but the NOAA site mutters about proximity to coasts giving confusing info, so it looks as if the resolution is not that high or frequent.

I don't think it answers OP's search for currents info. There are surface currents, mainly wind generated and possibly very local, and sub-surface ones which may derive from persistent wind and/or thermal inputs many miles distant.


A couple of years ago there was discussion here on the currents at Messina, Sicily, and someone linked to pics showing upper surface currents and some really long period deep down waves and their directions. Something to do with salinity ?


EDIT
perhaps this

http://www.sciencedirect.com/science/article/pii/S0422989408704550

though I can't access the full paper.

 

[whipper_snapper]

Thanks all, some very interesting sites. But, as you say, not what I was hoping for.

There are a strong series of currents running North and West from Madagascar and North up the coast of Mozambique, Tanzania and Kenya, up to 4 or 5 knots at some times in some places, with back eddies. So it makes a huge difference to get them right. They are at the maximum when the south monsoon has been blowing for a few months, but continue to flow against the wind during the North monsoon. Some method of seeing the speed and direction over the whole area for any given time would be extremely valuable, and I am sure that must be true of many other areas.

Pilot charts are very useful, but don't have anything like the resolution needed for hopping in and out of the current depending on your route. I had hoped that someone had modelled the whole ocean and allowed it to be combined with weather history to provide accurate information, but thinking about it, I realise that is quite ambitious. Looks like I will have to rely on simply looking at GPS speed and track vs heading and speed through the water that works but doesn't allow big picture planning.

It would be cool if there was a system for boats to report those numbers to a central place to crowd source current data.

Thanks again

 

[KellysEye]

>Interesting site. I wonder how they get to that level of detail - ie how accurate are all of those eddies in the Atlantic, and how much do they change.

An example of change is in the summer the Gulfstream crosses the Atlantic curves down south and runs down the Spanish and Portuguese Atlantic coasts, it about 2 knots. When sailing north well off Biscay we picked up a Gulfstream counter current and our speed went from 6 knots to 9.5.

 

[oldvarnish]

Pilot charts are very useful, but don't have anything like the resolution needed for hopping in and out of the current depending on your route. I had hoped that someone had modelled the whole ocean and allowed it to be combined with weather history to provide accurate information, but thinking about it, I realise that is quite ambitious. Looks like I will have to rely on simply looking at GPS speed and track vs heading and speed through the water that works but doesn't allow big picture planning.

It would be cool if there was a system for boats to report those numbers to a central place to crowd source current data.

Thanks again

I have no experience of this area, but I tried to play the inshore currents etc down the S America coast. I decided it was a waste of effort - too unpredictable. I reckoned it all averaged out over the month; sometime with you, sometimes against you. It could change from 1kt fair to 1kt foul within a few miles.

 

[Strolls]

Interesting site. I wonder how they get to that level of detail - ie how accurate are all of those eddies in the Atlantic, and how much do they change.

http://earth.nullschool.net/about.html

"ocean surface current estimates - updated every five days

Ocean Currents Data - OSCAR Earth & Space Research, http://www.esr.org/oscar_index.html"​

 

[Roberto]

Some method of seeing the speed and direction over the whole area for any given time would be extremely valuable, and I am sure that must be true of many other areas.

Would something like this be of any use?
Mercator model available in grib format, free data, 0.25° native grid, daily forecast up to 7 days (IIRC); this is what Madagascar - SE Africa may look like

 

[Roberto]

Otherwise, this is from the RTOFS model, also available via grib

 

[ianat182]

I peruse the Pprune website which is currently discussing the MH370 aircraft loss in the Indian Ocean. Surveys of the believed crash areas are still in progress but a 'flaperon ' has turned up on Reunion Island some thousand miles from the current search area, prompting much discussion as to the currents as far as Madagascar.
wikipedy.com/images-o/ocean-current.jpg has been one of the quoted references; a further reference is made to an oceanographer named Eric van Sebille which could be a search item for any chart or data. Also the OSCAR Ocean surface current analysis and data from NOAA in real time (already mentioned earlier in this thread).
The subject appears to be divided into at least three variables,heat,surface winds / currents and deep Ocean currents.
No trace of the aircraft other than the above wreckage has been found to date after several thousand square miles and approaching 3 years search.

Hope this helps

ianat182

 

[RobbieW]

OCPN has a Climatology plugin that shows surface currents based on data from http://podaac.jpl.nasa.gov/dataset/OSCAR_L4_OC_third-deg (1992 to 2012). The resolution appears fairly coarse but that could just be the representation