Loop Current position and size

[hurricanetrack]

Check out the latest NAVO map:

https://oceanography.navy.mil/legacy/we ... 19/0-0-5/0

It shows the Loop Current very well. I am amazed at how deep in to the GOM it extends. While it can certainly look a lot different than this in say, late August, it is interesting to see now. Can anyone throw their ideas in as to why it is situated like this right now? The darn thing almost extends to the shores of Louisiana!

[AJC3]

Hi Mark,

My hastily composed SWAG would be that the cool weather this winter has produced a more frequent northerly or perhaps northeasterly flow over the eastern Gulf of Mexico than usual. Because of Ekman turning the surface current will be deflected 45 degrees to the right of the surface wind, so a northerly wind would cause some westward deflection of the current, and a northeast wind even moreso.

Of course there are eddys that also form along the west wall of the current, so that may be part of it as well.

[wxman57]

I was thinking the same thing. It's not that the loop current is different from previous years, it's that the eastern Gulf has seen more cold surges this winter, dropping the SSTs east of the loop current.

[Ed Mahmoud]

I was thinking the same thing. It's not that the loop current is different from previous years, it's that the eastern Gulf has seen more cold surges this winter, dropping the SSTs east of the loop current.

I know very little about the Loop Current, except from gazing (not reading) professional journals in petroleum engineering (ocean dynamics isn't my cup of tea) it is really important to offshore rig and platform design.


BTW, patting myself on the back because before I even read link on Ekman dynamics, I was saying to myself "I bet the Coriolis effect is involved in this".

Ouch, pulled a muscle.

[cycloneye]

There is the finger in the GOM.



http://www.osdpd.noaa.gov/PSB/EPS/SST/climo.html

[MGC]

My guess is that it is an eddy that will break off the loop current and migrate west....MGC

[wxman57]

My guess is that it is an eddy that will break off the loop current and migrate west....MGC

Eddies do break off every year or so, but that whole top part of the loop current won't break off. Typically, the detached eddies are much smaller. They're actually given names, following the alphabet from A-Z. Eddies generally travel west toward Texas then south toward the BoC where they spin down and die.

The loop current and eddies affect deepwater operations off the TX/LA coasts. The speed of the current can approach 4 kts at times, producing a significant force on semisubmersible platforms during installation. We provided weather support for the installation of the Atlantis Project in Green Canyon off the mid LA coast a few years back. They actually had to install the $2 billion dollar platform in the middle of an eddy, passing across 3kt currents to get inside.

[gatorcane]

I was thinking the same thing. It's not that the loop current is different from previous years, it's that the eastern Gulf has seen more cold surges this winter, dropping the SSTs east of the loop current.

Reynold's SST anomaly analysis shows that the SSTs in the North Central GOM are running quite a bit above normal around the northern tip of the Loop Current. While the Eastern GOM as you say is quite a bit below normal. Clearly the reason is what you explained -- the Eastern GOM has dealt with two big arctic blasts this winter so far both of which brought mainland Florida temperatures into the lower to mid 30s as far south as inland Southern Monroe and Miami-Dade in extreme Southern Florida.

Actually looking ahead, the ECMWF is hinting at another arctic blast at 144 hours from now (Sun. Feb. 22) although it doesn't appear to be as severe as the last two blasts. Should this verify, it should keep the SSTs in the Eastern GOM much below normal through the rest of this month and perhaps further allow Ekman turning forces to keep the loop current pervasive up through the North Central GOM.

[brunota2003]

Where can I get an archive of those images going back several years or more?