I was looking up Sarasota, Florida and one thing lead to something else entirely, which seems to be a pattern…
First I got a look at the Seminole Indians, who have very straight European noses and look more Basque than Asian
Then I wandered…
Into the Loop Current. More on that below and some rampant speculation.
Which ended at this interesting temperature map of The Gulf Of Mexico and Florida waters from the U.S. Navy. Interesting side bar being that they map where it is just too damn shallow to take any real ship, and overlay the actual “coastline” on that.
First off, this has an interesting capture of a loop current where that warm water rises up into the Gulf of Mexico between Yucatan and Cuba and puts that green blob off the west coast of Florida. Sometimes it is there, sometimes not. This matters for hurricane formation among other things.
But the next thing I noticed was that there is a roughly 12 degree F range in about 25 degrees of latitude to the Sea Surface Temperature SST. In some parts of the map, 5 F in 10 Lat.
Now IF a “well mixed gas” like CO2 were driving temperatures, would they range over 5 F in 10 degrees? Really? Since SST drives land temps for anything near water, and Florida is very much driven by the surrounding water, the land temps will show similar (though more widely ranging) variation with latitude. Which leaves me wondering:
Is temperature driven by a Magic Gas in the air, or by insolation with latitude? This map seems to show strong banding with latitude and strong correlation with ocean currents. Gas not so much.
To understand temperatures on land, you really MUST look at latitude, insolation, and ocean currents.
The Loop Current
There’s an interesting phenomenon where a warm “loop” rises up into the Gulf of Mexico. From that Wunderground link above:
The Gulf of Mexico Loop Current: A Primer
By Jeffrey Masters, Ph.D. — Director of Meteorology, Weather Underground, Inc.
The Loop Current is an ocean current that transports warm Caribbean water through the Yucatan Channel between Cuba and Mexico. The current flows northward into the Gulf of Mexico, then loops southeastward just south of the Florida Keys (where it is called the Florida Current), and then just west of the westernmost Bahamas. Here, the waters of the Loop Current flow northward along the U.S. coast and become the Gulf Stream. With current speeds of about 0.8 m/s, the Loop Current is one of the fastest currents in the Atlantic Ocean. The current is about 200 – 300 km (125 – 190 miles) wide, and 800 meters (2600 feet) deep, and is present in the Gulf of Mexico about 95% of the time. During summer and fall, the Loop Current provides a deep (80 – 150 meter) layer of vary warm water that can provide a huge energy source for any lucky hurricanes that might cross over.
Now the Gulf Stream eventually reaches Europe and the Arctic regions where it keeps things much warmer than otherwise. All that loverly tropical sunshine warming all that Caribbean water ends up deposited in Merry Olde England and surrounding.
So what happens during an Ice Age Glacial?
From that wiki on Sarasota:
First off, all those shallow shelf areas become land. No longer collecting solar energy into the Gulf Stream, but instead putting it into the air. That is one heck of a lot of energy NOT going to the UK or the Arctic.
Second, a broad swath of area for shallow currents is cut off. I have no idea what the water flows would look like then, nor I suspect does anyone else. It becomes a very different hydrological feature then; one with global impact. I do think it is fair to say that the Gulf Stream would be far weaker and with much less heat in it, given the reduction on collecting area and channels for heat driven current flow.
I would guess that the loop current stops, and that the flow of energy to the arctic is drastically cut down. Perhaps that is part of the mechanism (and maybe a key part?) of the hysteresis that puts us into an Ice Age Glacial state instead of a interglacial. Rampant speculation, I know. BUT, that is one heck of a lot of water NOT warming and NOT melting ice at the north pole.
There is evidence of icebergs ploughing grooves into the mud off the Atlantic coast of Florida during an Ice Age Glacial. IMHO that is strong evidence that hot water isn’t “going there”. Would an iceburg really swim ‘upstream’ against the Gulf Stream and survive such a hot water bath all the way to Florida? Somthing else is going on in the Atlantic, then.
Icebergs once drifted to Florida, new climate model suggests
October 12, 2014
University of Massachusetts at Amherst
Using a first-of-its-kind, high-resolution numerical model to describe ocean circulation during the last ice age about 21,000 year ago, oceanographers have shown that icebergs and meltwater from the North American ice sheet would have regularly reached South Carolina and even southern Florida. The models are supported by the discovery of iceberg scour marks on the sea floor along the entire continental shelf.
Much of the rest of that article is rampant computer speculation (i.e. models) about meltwater and changes in ocean currents. Hit the link to read it.
For me, what matters is those marks on the ocean floor.
IMHO, a key driver of the oscillation between ice age Glacial and Interglacial states must be the change in warm tropical water flows to the Arctic. For that, Florida, and the Gulf of Mexico, hydrological changes with sea level drop must be important.
What is also very clear from that SST map, is that temperatures are controlled by currents (note the hotter Pacific side of Panama where currents do not take the heat away to Europe…), latitude (note the nice temperature banding with latitude on the Atlantic side), and insolation (it changes with season, not shown). Again, CO2 not so much…