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Post by missouriboy on Apr 18, 2015 23:16:29 GMT
weather.unisys.com/surface/sst_anom.gifThe North Atlantic Drift now seems to be petering out mid-Atlantic. Petawatts of heat are now going missing in the Arctic. Should make for an interesting ice recovery next Northern Hemisphere winter. Meanwhile, there will be snow on the hills to the East of Melbourne tomorrow, above 900 meters. They had widespread snowfall in NZ last week. It looks like the North Atlantic drift is turning into the mid-Atlantic drift There always was a returning branch that turned South along the West Africa coast, but that seems to be the main branch at the moment.  This could alter a lot of things if there is some chaotic flip that has happened not stopping the North Atlantic Drift but rerouting it. We have shown that there was a slowdown in the AMOC transport between 2004 and 2012 amounting to an average of ?0.54 Sv yr?1 (95% c.i. ?0.08 to ?0.99 Sv yr?1) at 26 N, and that this was primarily due to a strengthening of the southward flow in the upper 1100m and a reduction of the southward transport of NADW below 3000 m. This trend is an order of magnitude larger than that predicted by climate models associated with global climate change scenarios, suggesting that this decrease represents decadal variability in the AMOC system rather than a response to climate change. (Smeed et al., 2014) Ocean Sci., 10, 29–38, 2014 www.ocean-sci.net/10/29/2014/doi:10.5194/os-10-29-2014 I note the the 'big cold blob' in the N. Atlantic has expanded from about Nov. 2014 into a crescent shape extending from Eastern N. America across the Atlantic and southward along the African coast. But it's still warm north of the blob??? I know they are anomaly maps but how does that happen??? weather.unisys.com/archive/sst/sst_anom-141109.gifweather.unisys.com/archive/sst/sst_anom-150412.gifColor scheme utilized prior to Nov. makes visual assessment a pain. Smeed et al.'s analysis doesn't sound like the standard 'fresh melt water slows the conveyor argument'? While they state that the AMOC has slowed, more warm surface water is moving east & back to the south. Is the overturning current only the northern part? Or is it being forced (blocked?) eastward??? Fascinating. Flearider's Antarctic melt water gone north scenario is interesting. Is there a way to test it? Would existing sensor arrays pick it up?  |
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Post by acidohm on Apr 23, 2015 16:25:38 GMT
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Post by nautonnier on Apr 23, 2015 16:57:43 GMT
I must admit to disliking the term 'teleconnection' what is meant is a correlation without any known mechanism. So call it a correlation. If you were to think of the oceans as a wide shallow lave lamp with the power switched low then change the rate of rotation of the Earth (a LOD change) then you would expect the layers in the lava lamp to slop and the effect could be cold upwelling and warm downwelling. If the oceans were all identical and the same area one would expect the same effect on the layers upwelling/downwelling. WIth some differences between Pacific and Atlantic including layers and currents then these otherwise identical movements will be modulated by the shape of the land the size of the oceans and their depth. The underlying similarity in response to an LOD change should still be there. If LOD is linked to lunar and solar motions and the solar orbit around the galazy is modulated by the planets. Then there is yet another mechanism for the planets to affect Earth's climate. |
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Post by missouriboy on Apr 23, 2015 18:49:33 GMT
This is a 'GREAT' find (for me anyway)! Thank you!!!!!! Has anyone found a similar tool/page for scrolling through a temporal Jet Stream time series? |
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Post by acidohm on Apr 23, 2015 19:39:09 GMT
This is a 'GREAT' find (for me anyway)! Thank you!!!!!! Has anyone found a similar tool/page for scrolling through a temporal Jet Stream time series? My favorite weather forecast site does one but only back to jan 2014.......glad you like the above missouriboy!! It had me transfixed for quite a while  |
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Post by acidohm on Apr 23, 2015 19:51:55 GMT
Missouriboy, your a data guy??
Pulling up the argo floats on google earth which plots their routes as they drift in the current for anything up to 10 years or so ago, specifically i'm looking at the NAD. There are dozens of these things in N Atlantic along with each point of the plot giving dates etc.
Thinking these could a good way to determine current er, currents eg, is NAD not making it as far north etc. I am however starting to 'swim' in info.....how would you suggest making sense of it all...if possible??
(excuse the weak puns.....!)
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Post by flearider on Apr 23, 2015 22:00:37 GMT
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Post by missouriboy on Apr 24, 2015 0:13:40 GMT
Missouriboy, your a data guy?? Pulling up the argo floats on google earth which plots their routes as they drift in the current for anything up to 10 years or so ago, specifically i'm looking at the NAD. There are dozens of these things in N Atlantic along with each point of the plot giving dates etc. Thinking these could a good way to determine current er, currents eg, is NAD not making it as far north etc. I am however starting to 'swim' in info.....how would you suggest making sense of it all...if possible?? (excuse the weak puns.....!) Yes ... in my past life I piloted geographic information systems and swam in terrabytes of digital imagery and other geo-referenced info. I miss my expensive software packages that were paid for by others. Been meaning to download some freeware GIS packages, but just haven't done it yet. For point or grid-based ocean data, that would certainly be the way to go. Stacked data models fed with whatever you could beg, borrow or pilfer that's tagged to a coordinate system. Makes it a lot easier to track and correlate different spatial data sources. In this approach, space becomes your reference, and your data merely 'swim' through  . Of course, all that programming takes some time. GRASS used to be freebee package that had both raster and vector handling capabilities that would run on a good laptop. Haven't looked, but I'm sure the Argo data would come complete with coordinates otherwise they couldn't plot it on a map. What's the source address on those? I sure like the Earth datasets: earth.nullschool.net/#current/ocean/surface/currents/orthographic=-37.16,35.86,502 Probably propriatary, but maybe not. Right off, I don't know what their inputs are for plotting NAD in the above link, but depending on what you're trying to do, it may already be there ... if you can get access. If you have the time, you can learn the rudiments of simple GIS overlay relatively quickly, if it's a user friendly package. Might check ESRI as well. Their old ARCVIEW software versions with limited capabilities were also free. Actually, I need to check both of these as well. Otherwise, it's a pain in the buns to handle continuous spatial data in a spreadsheet format. You could, by creating your own reference grids (by lat-long or otherwise) and transfer visual observations or digital data sets to it ... just like you'd handle weather station data. It may just depend on how much time you want to devote to it. If I can help you out, I'd be happy to try. OLD RULE OF THUMB: Other people's data are cheaper than creating your own (usually). |
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Post by acidohm on Apr 24, 2015 21:02:23 GMT
Thanks Missouriboy, Looking at the earth.nullschool stuff, this may be most appropriate for keeping pace with current NAD currents, indeed worldwide. This is the source of what you see on their excellent animation..... www.esr.org/oscar_index.htmlOverview Ocean Surface Current Analyses Real-time (OSCAR) is a project to calculate ocean surface velocities from satellite fields. Surface currents are provided on global grid every ~5 days, dating from 1992 to present day, with daily updates and near-real-time availability. The data is freely available through two data centers operated by NOAA and NASA. The NASA PO.DAAC site (http://podaac.jpl.nasa.gov) serves OSCAR currents on both 1 degree and 1/3 degree grid spacing in netcdf format only. This is the more reliable data source. The NOAA site (www.oscar.noaa.gov) provides data in both downloadable images and netcdf format. Validation statistics are also provided through this site. Both sites have additional information about the calculation of OSCAR. The OSCAR product is a direct computation of global surface currents using satellite sea surface height, wind, and temperature. Currents are calculated using a quasi-steady geostrophic model together with an eddy viscosity based wind-driven ageostrophic component and a thermal wind adjustment. The model calculates a surface current averaged over the top 30m of the upper ocean. ARGO does offer free access to all its data... GDAC data stream (for NetCDF Argo files) For users interested in manipulating the actual Argo NetCDF files, the GDACs should be the route to access Argo data. Both GDACs offer access to the complete Argo data collection, including float metadata, detailed trajectory data, profile data and technical data all in NetCDF format. The data is organized in either a geographic (by ocean basin) or a Data Assembly Centre (DAC) manner and is provided via HTTP and FTP as well as through data browsers and other portals like OpenDAP, OGC-WCS, etc. It is important to understand the naming system of the files as well as the variable names and quality control flags within each data file. See the ADMT Documentation page for the Argo User's Manual and the Argo quality control manual for more information. Tools for assisting with Argo data handling Some people have difficulty working with NetCDF format files on the Argo GDAC servers. Information on NetCDF can be found on the UCAR website. Here is a simple Matlab program to read in a netCDF Argo file. Users are encouraged to share the tools they develop with the rest of the Argo Community. The biggest difference between the 2 sets is the way the systems operate, as OSCAR uses satellites to measure the top 30m of the ocean, ARGO buoys are mainly drifting at 1500-2000m depth, only rising intermittently to capture and transmit data. The NAD however is up to 1000m deep so probably not truly reflected in the ARGO data. |
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Post by missouriboy on Apr 25, 2015 13:35:52 GMT
Thanks Missouriboy, Looking at the earth.nullschool stuff, this may be most appropriate for keeping pace with current NAD currents, indeed worldwide. This is the source of what you see on their excellent animation..... www.esr.org/oscar_index.htmlOverview Ocean Surface Current Analyses Real-time (OSCAR) is a project to calculate ocean surface velocities from satellite fields. Surface currents are provided on global grid every ~5 days, dating from 1992 to present day, with daily updates and near-real-time availability. The data is freely available through two data centers operated by NOAA and NASA. The NASA PO.DAAC site (http://podaac.jpl.nasa.gov) serves OSCAR currents on both 1 degree and 1/3 degree grid spacing in netcdf format only. This is the more reliable data source. The NOAA site (www.oscar.noaa.gov) provides data in both downloadable images and netcdf format. Validation statistics are also provided through this site. Both sites have additional information about the calculation of OSCAR. The OSCAR product is a direct computation of global surface currents using satellite sea surface height, wind, and temperature. Currents are calculated using a quasi-steady geostrophic model together with an eddy viscosity based wind-driven ageostrophic component and a thermal wind adjustment. The model calculates a surface current averaged over the top 30m of the upper ocean. ARGO does offer free access to all its data... GDAC data stream (for NetCDF Argo files) For users interested in manipulating the actual Argo NetCDF files, the GDACs should be the route to access Argo data. Both GDACs offer access to the complete Argo data collection, including float metadata, detailed trajectory data, profile data and technical data all in NetCDF format. The data is organized in either a geographic (by ocean basin) or a Data Assembly Centre (DAC) manner and is provided via HTTP and FTP as well as through data browsers and other portals like OpenDAP, OGC-WCS, etc. It is important to understand the naming system of the files as well as the variable names and quality control flags within each data file. See the ADMT Documentation page for the Argo User's Manual and the Argo quality control manual for more information. Tools for assisting with Argo data handling Some people have difficulty working with NetCDF format files on the Argo GDAC servers. Information on NetCDF can be found on the UCAR website. Here is a simple Matlab program to read in a netCDF Argo file. Users are encouraged to share the tools they develop with the rest of the Argo Community. The biggest difference between the 2 sets is the way the systems operate, as OSCAR uses satellites to measure the top 30m of the ocean, ARGO buoys are mainly drifting at 1500-2000m depth, only rising intermittently to capture and transmit data. The NAD however is up to 1000m deep so probably not truly reflected in the ARGO data. Many thanks Acidohm. Irrespective of my cynicism on government bureaucracies, many good products ARE available from those who focus on the science and '86' the religious perspective. |
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Post by acidohm on Apr 25, 2015 19:57:42 GMT
Thanks Missouriboy, Looking at the earth.nullschool stuff, this may be most appropriate for keeping pace with current NAD currents, indeed worldwide. This is the source of what you see on their excellent animation..... www.esr.org/oscar_index.htmlOverview Ocean Surface Current Analyses Real-time (OSCAR) is a project to calculate ocean surface velocities from satellite fields. Surface currents are provided on global grid every ~5 days, dating from 1992 to present day, with daily updates and near-real-time availability. The data is freely available through two data centers operated by NOAA and NASA. The NASA PO.DAAC site (http://podaac.jpl.nasa.gov) serves OSCAR currents on both 1 degree and 1/3 degree grid spacing in netcdf format only. This is the more reliable data source. The NOAA site (www.oscar.noaa.gov) provides data in both downloadable images and netcdf format. Validation statistics are also provided through this site. Both sites have additional information about the calculation of OSCAR. The OSCAR product is a direct computation of global surface currents using satellite sea surface height, wind, and temperature. Currents are calculated using a quasi-steady geostrophic model together with an eddy viscosity based wind-driven ageostrophic component and a thermal wind adjustment. The model calculates a surface current averaged over the top 30m of the upper ocean. ARGO does offer free access to all its data... GDAC data stream (for NetCDF Argo files) For users interested in manipulating the actual Argo NetCDF files, the GDACs should be the route to access Argo data. Both GDACs offer access to the complete Argo data collection, including float metadata, detailed trajectory data, profile data and technical data all in NetCDF format. The data is organized in either a geographic (by ocean basin) or a Data Assembly Centre (DAC) manner and is provided via HTTP and FTP as well as through data browsers and other portals like OpenDAP, OGC-WCS, etc. It is important to understand the naming system of the files as well as the variable names and quality control flags within each data file. See the ADMT Documentation page for the Argo User's Manual and the Argo quality control manual for more information. Tools for assisting with Argo data handling Some people have difficulty working with NetCDF format files on the Argo GDAC servers. Information on NetCDF can be found on the UCAR website. Here is a simple Matlab program to read in a netCDF Argo file. Users are encouraged to share the tools they develop with the rest of the Argo Community. The biggest difference between the 2 sets is the way the systems operate, as OSCAR uses satellites to measure the top 30m of the ocean, ARGO buoys are mainly drifting at 1500-2000m depth, only rising intermittently to capture and transmit data. The NAD however is up to 1000m deep so probably not truly reflected in the ARGO data. Many thanks Acidohm. Irrespective of my cynicism on government bureaucracies, many good products ARE available from those who focus on the science and '86' the religious perspective. Agreed, however, dya think we should be archiving all thus raw data ourselves...you know....just in case |
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Post by missouriboy on Apr 26, 2015 1:52:57 GMT
Many thanks Acidohm. Irrespective of my cynicism on government bureaucracies, many good products ARE available from those who focus on the science and '86' the religious perspective. Agreed, however, dya think we should be archiving all thus raw data ourselves...you know....just in case Ya never know!!! And it's handier to use if it's around ... and disk storage is cheap. And the housekeeping may keep ya young.  |
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Post by flearider on Apr 28, 2015 11:11:54 GMT
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Post by missouriboy on May 13, 2015 1:32:05 GMT
The 'blue blob' has expanded again. It now appears to cover ~40% of the North Atlantic (above 20 degrees north). AMO values for March and April are now negative (the lowest monthly values since 2009). www.esrl.noaa.gov/psd/data/correlation/amon.us.dataHow low will it go? Looks like a monster, facing west, eye to Greenland, jaws sucking in the Gulf Stream. Did anyone notice that the published PDO values for the last four months are higher than anytime since 1997?  |
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Post by nautonnier on May 13, 2015 15:43:44 GMT
Interesting that the SST map there shows the track of early 'tropical; sub-tropical storm Ana - which also means that the Gulf Stream at that point has not got as much heat as would be expected, it was only a minor storm. So the heat being shown by the satellites on the East coast off Florida, Georgia and Carolinas is escaping surface heat not an indication of a strong warm current to 700ft or deeper.
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. Of course, all that programming takes some time.