Watch recent hurricanes cool the Atlantic

Two hurricanes approaching the coast of the United States, with the second hurricane slowed due to cooler waters caused by the track of the first.

The Atlantic has been running warm lately, but that’s because there’s been little happening with Nature’s natural heat transporters. WUWT commenter SteveM pointed out something interesting in the latest SST image from NESDIS, but before we have a look at the animation I developed from that imagery, I thought we should have a look at the role that hurricanes play as heat engines.

First an animation from Goddard Space Flight Center:

And another, showing how the heat transport and surface cooling process operates.

From NASA SVS: As water vapor evaporates from the warm ocean surface, it is forced upward in the convective clouds that surround the eyewall and rainband regions of a storm. As the water vapor cools and condenses from a gas back to a liquid state, it releases latent heat. The release of latent heat warms the surrounding air, making it lighter and thus promoting more vigorous cloud development.

Now let’s watch this simple animation of the last two weeks of Sea Surface Temperatures and you’ll see the cool water tracks left by hurricanes Daniel and Earl:

click to enlarge

You can see the cool tracks in the last frame. Note also the large and growing La Niña off the west coast of South America. It’s turning deep purple and on to black. Way cool.

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Moebius
September 8, 2010 4:03 am

more hurricans = more cooling may be?

Peter H
September 8, 2010 4:16 am

Yes, I think it’s reasonable to say they might have cooled the sea surface.
But what about at greater depths? I’m not sure, having read comments elsewhere, the Atlantic tropical disturbances seen so far this year have affected the temperature in depth (heat content) to a meaning full extent?

Njorway
September 8, 2010 4:43 am

What about Sinabung and global temperatures?

Steve Keohane
September 8, 2010 4:45 am

Someone pointed this out a year or two ago here, the cool hurricane tracks in the SST showed up well then too. A typical hurricane has something on the order of 6.0 x 10^14 Watts per day just in condensation updraft, dumping heat 8 miles into the upper troposphere.
http://www.aoml.noaa.gov/hrd/tcfaq/D7.html

September 8, 2010 4:52 am

AOT
Two Asteroids to Pass by Earth Wednesday
PASADENA, Calif. – Two asteroids, several meters in diameter and in unrelated orbits, will pass within the moon’s distance of Earth on Wednesday, Sept. 8.
The Catalina Sky Survey near Tucson, Ariz., discovered both objects on the morning of Sunday, Sept. 5, during a routine monitoring of the skies. The Minor Planet Center in Cambridge, Mass., first received the observations Sunday morning, determined preliminary orbits and concluded that both objects would pass within the distance of the moon about three days after their discovery.
http://www.nasa.gov/topics/solarsystem/features/asteroid20100907.html

Tom in Florida
September 8, 2010 5:37 am

The next question would be : What happens to the air that has been warmed by the release of the latent heat and where does it go?

John Marshall
September 8, 2010 5:41 am

Wind will cool surfaces, including oceans, because of evaporation, due to the wind energy, and this requires heat which is extracted from the water. It is good to see that one hurricane will reduce the power of a following one.

BSax
September 8, 2010 5:54 am

Which raises the question: where did Katrina get its energy? Three hurricanes had already passed over the Gulf (if memory serves) before Katrina arrived on the scene. What heat reserve caused the massive intensification of the storm on the night before landfall?

mike sphar
September 8, 2010 6:07 am

September looks to be a bit less intense than August was. Maybe late in the month some action. Cuirrently the MDR (Main Development Region) is pretty slack.

docattheautopsy
September 8, 2010 6:10 am

Very cool to see thermodynamics in action.
But that La Nina looks ominous!

September 8, 2010 6:25 am

Can someone please explain to me why the waters on the Pacific side of where Central and South America meet are so warm? Especially given that the niña waters near it are so cold…

September 8, 2010 6:26 am

BSax
Time matters. In September the sun can still heat a lot of water in a short time. There are also currents which don’t suspend operation during hurricanes. Warm water from the western gulf moves eastward continually.

RockyRoad
September 8, 2010 6:27 am

Of course hurricanes cool the Atlantic. If the reverse were true, we’d just have more and more hurricanes; the tipping point would eventually be reached until it was one continuous hurricane.

PJB
September 8, 2010 6:29 am

Alex passed through the Gulf of Campeche and left a trail of “cooler” water. Hermine ramped up in the same area and had no trouble using those warm and deep waters.
Often, a trailing cyclone will run afoul of shear generated in the upper atmosphere by the outflow of the preceding system. There are also the general atmospheric systems to consider. They affect the track of the system and will affect subsequent systems in different ways.
A most complex and complicated meteorology. Clearly not defined by any one particular agent, especially not CO2 as a GG.

Bernd Felsche
September 8, 2010 6:33 am

More convection at the surface leads to greater evaporation and faster heat loss from the surface. And the clouds reduce incoming heating.
Who’d have thought?
[/sarcasm]

September 8, 2010 6:37 am

I can understand why a following hurricane might be weakened by cooler waters, but I don’t see why this would slow it. Repulsion between the two vortices (if they are rotating the same way) might do it.

Volt Aire
September 8, 2010 6:47 am

I thought more water in the air = more warming since water vapor causes positive feedback. Those hurricane paths should be boiling.

Ian W
September 8, 2010 6:53 am

From http://www.aoml.noaa.gov/hrd/tcfaq/D7.html the reference mentioned by Steve Keohane
An average hurricane in one day uses the equivalent of 200 times the world-wide electrical generating capacity for that day.
That puts the power of nature into perspective.

david
September 8, 2010 7:02 am

Peter H.
“Yes, I think it’s reasonable to say they might have cooled the sea surface”
You can’t have warm water laying under cool water for very long, they will mix. As we are talking a few tens of feet, that would happen within hours. However the hurricane really draws out a lot of the heat even at those depths.
You can see my point by watching the SST for a while (there will be an update on Thursday I think) and you will see that the track remains. The hurricane pulls out most of the warm water and leaves the area 5-10F cooler than prior. Deeper water rises and remixes with the surface water but still remains cool until the sun and ocean currents mix it out. You might see the track until next week or longer.
I am not sure but I also think there is a mechanical effect too. Kind of like stirring up mud in a puddle. It rises and then spreads out across a big area of the puddle. The cold water below is pulled up by the hurrican to some degree, but also the mechanics of the storm itself. It is a low pressure, water is drawn into it, so the sea rises several feet, it is cooled and then as the storm passes the water spreads out. As it does so, I suspect cool deep water is pulled to the surface.

Sandy
September 8, 2010 7:06 am

I’m with EarthDog.
How do you get -6C water right next to +2.5C water with little or no visible gradient,
WUWT ??

September 8, 2010 7:25 am

And to keep to the theme of this post, the 2010 hurricane season, of course, has the 2009/10 El Nino to thank in part for the elevated tropical North Atlantic Sea Surface Temperatures. But how does an El Niño in the central equatorial Pacific raise SST in the tropical North Atlantic, when the Americas separate the two bodies of water?
The change in the location of the warm water in the tropical Pacific during an El Niño changes the location of the convection associated with that warm water. In other words, the convection and associated precipitation accompany the warm water from the western to the central tropical Pacific during an El Niño event. This changes coupled ocean-atmosphere processes globally. In the tropical North Atlantic, an El Niño causes trade winds to slow. Since there is less evaporative cooling, and since there is less upwelling of cooler waters from below the surface, Tropical North Atlantic Sea Surface Temperatures rise. I discussed this in my Intro to ENSO post:
http://bobtisdale.blogspot.com/2010/08/introduction-to-enso-amo-and-pdo-part-1.html
For those who would like the effect on the North Atlantic described in more technical detail, refer to Wang (2005), “ENSO, Atlantic Climate Variability, And The Walker And Hadley Circulation.”
http://www.aoml.noaa.gov/phod/docs/Wang_Hadley_Camera.pdf

Douglas DC
September 8, 2010 7:31 am

Very interesting and I wonder if the NAO is on its way to a cooling period too.
Seems Bastardi talked about that….

Tim Clark
September 8, 2010 7:37 am

Slightly OT.
But to the warmers that think hurricane numbers and intensity are higher
now…………………….
… On this date in weather history…
In 1900… the worst weather disaster in United States
history occurred when a hurricane struck Galveston Texas.
The hurricane unleashed winds around 120 mph and a 20
foot storm surge washed over the island. Most buildings
were demolished or swept away and around 3,600 houses
were destroyed. Damage estimates were around $30
million. Adjusting for inflation… this would equate to
around $670 million. Around 6,000 people drowned in
Galveston with another 1,200 killed elsewhere.Following
the hurricane the surf was 300 feet inland from the
former shore line. In 1989… thunderstorms developing
along a stationary front produced torrential rains in
parts of Nebraska… where 5 to 9 inches drenched Lincoln.
The 4.68 inches measured at the Airport is a record for
the date. An unofficial report of 11 inches was received
from Holmes Park. Parts of western Iowa were soaked with
6 to 6.5 inches of rain. The 5.89 inches measured in
Shenandoah that set a record for the date flooded the
basements of 80 to 90 percent of the homes in the area.

Mike M
September 8, 2010 7:37 am

Volt Aire – Right on! If there was ANY credibility to CAGW theory in regard to water vapor causing an ‘amplification’ of warming we ought to see at least ‘something’ within the micro-climate of a hurricane that exemplifies that notion. Such is as non-existent as man made global warming. We keep trotting out real world examples contrary to their theory and they just keep trotting out incomplete/incorrect models.; spin away James Hansen…

Leon Brozyna
September 8, 2010 7:46 am

I’d been watching the SST maps lately and noticed something else. Of course, when a hurricane passes over the warm waters its effect is like that of an egg beater stirring up and mixing the waters, so after a hurricane passes, the surface waters become cooler. I also noticed that the effect doesn’t appear immediately. I’ll be watching the waters off Nova Scotia to see if the cooling finally appears by the weekend.

September 8, 2010 8:06 am

Peter H says: “But what about at greater depths? I’m not sure, having read comments elsewhere, the Atlantic tropical disturbances seen so far this year have affected the temperature in depth (heat content) to a meaning full extent?”
I don’t believe OHC datasets would show a noticeable change due to hurricanes. Year-to-year sea surface temperature fluctuations for the entire North Atlantic basin hardly make a dent, so trying to find a variation in a small area caused by a localized event would be near to impossible. Even large volcanic eruptions are hard to find in some OHC subsets. Rest assured, though, that the North Atlantic OHC is dropping and has been for a few years:
http://i49.tinypic.com/5ebpua.jpg
The graph is from this post:
http://bobtisdale.blogspot.com/2010/06/january-to-march-2010-nodc-ocean-heat.html

Gnomish
September 8, 2010 8:14 am

HEAT PUMP!
now we are getting somewhere!

Leon Brozyna
September 8, 2010 8:17 am

And suddenly Igor forms just south of Cape Verde islands. Sounds like a bad horror film.

CodeTech
September 8, 2010 8:22 am

Good to see Nasa’s graphic prowess… it actually looks slightly less convincing than something a second grader would do with today’s technology.
Maybe their visualization funding is going to their new primary function of appeasing a certain religion?

September 8, 2010 8:32 am

First:
Do you remember the last season Azores’ flooding rains?
The Pacific born El Niño crossed over the continent, as it wouldn’t exist as a barrier:
http://www.vukcevic.talktalk.net/LFC20.htm

September 8, 2010 8:33 am

docattheautopsy says: “But that La Nina looks ominous!”
As of last week, NINO3.4 SST anomalies were lower than they were for past strong La Nina events during the satellite era:
http://i53.tinypic.com/4volcg.jpg
Graph is from my most recent update:
http://bobtisdale.blogspot.com/2010/09/august-2010-sst-anomaly-update.html

September 8, 2010 8:35 am

So an area of up-welling pumps bringing cold water to the surface may actually slow or defect the hurricane a little as well as generate larger fisheries populations. Interesting.

September 8, 2010 8:36 am

Will there it be enough heat the next SH summer season as to warm up at least a feeble El Nino?, or , rather we’ll keep on sliding down in very cold and interesting times?

September 8, 2010 8:37 am

They cool the sea, but that heat must go somewhere? Where? It is emitted into space via IR, where increased levels of CO2 help cool the planet.

September 8, 2010 8:38 am
September 8, 2010 8:42 am

It seems hurricanes just peeled a thin warm skin from the ocean surface and there is little left around caribbean waters:
http://weather.unisys.com/surface/sst_anom.html

toyotawhizguy
September 8, 2010 8:47 am

Atlantic hurricanes also transport heat away from the tropics as they move northward. In the northeastern US, we usually see a 10 to 20 deg F temperature spike whenever the remnants of a hurricane pass through. Fortunately, they are almost always a Tropical Depression by the time they pass through my back yard.

dp
September 8, 2010 8:50 am

So the heat left the ocean and went into the atmosphere. Where is it now? Surely some has left the system when radiated into space, but the rest has been transported somewhere. Only that part that left the system has any immediate impact on the energy state of the planet. There’s also the follow-up question regarding where it went. Is it now in a form that is less or more difficult to radiate into space? It seems to me that if that energy is still in the atmosphere it has a better chance of leaving the system than it did when it was 100m under the sea surface.
Meanwhile, with all that was going on, the albedo of the Atlantic was significantly affected by the storm clouds, so heat did not reach the lower troposphere. It would seem that hurricanes are to stored energy what worms are to the garden. Not a bad thing to have around.

bubbagyro
September 8, 2010 8:55 am

BSax says:
September 8, 2010 at 5:54 am
Huh? Katrina went from a category 5 to a category 3, a dramatic drop, before landfall. Also, when talking about the oceans, there are thermoclines, i.e. areas of abrupt temperature differences with depth, that resist change. The first thermocline is often within a hundred feet down, then others until the benthic thermocline at which water is near freezing. Thermoclines happen because of horizontal currents at different depths. A similar reason is how we can have very cold areas adjacent to warm areas on the map without blending — these are surface currents that hold “streams” together. Remember that they may look right next to a warm area on a map, but we are talking about hundreds of miles on the globe.
Sometimes a strong hurricane will overcome the thermocline and totally mix the column if it is shallow enough. Also, there are haloclines that often must be overcome to effect mixing and these are very resistant.

Paul Loock
September 8, 2010 9:04 am

Please remember what Willis Eschenbach tells us about the cooling effect of tropical clouds. (http://wattsupwiththat.com/2009/06/14/the-thermostat-hypothesis/)
The top of a hurricane reaches the top of the troposphere. So the broadband-IR-emission of condensed water has not so much absorbing material above for backradiation and ensures effective cooling of the system in addition to shadowing the oceans surface.

bubbagyro
September 8, 2010 9:05 am

Enneagram says:
September 8, 2010 at 8:36 am
Good thought. I think we will wish we could have conserved some of this hurricane heat for during the coming solar dormant cycle instead of wasting it to space. I think those silly futurists we see on TV, who “invent” absurd devices so we can “live” hovering over Venus or Titan, could invent a ridiculous, hovering, insulated bladder to fill with warm air above a hurricane, then to be dispensed into the troposphere during the cold winters.
Uh oh! Now we may see such a show on Discovery Channel soon.

dp
September 8, 2010 9:31 am

Bubbagyro – don’t you suppose a cat5 hurricane might just be whipping any near-surface thermoclines to a frothy uniformity?

September 8, 2010 9:36 am

dp says:
September 8, 2010 at 8:50 am
So the heat left the ocean and went into the atmosphere. Where is it now?

Perhaps way up to the closest gravity center….or in orbit 🙂

Tenuc
September 8, 2010 9:51 am

Good to see our planets safety valve is blowing away the excess ocean heat. They all seem to fizzle out as they swing north and the warm moist air they carry can escape to space.
I wonder if the second half of the season will bring some stronger hurricanes on the scene, or is the sea going to become too cool to allow this to happen?

Chuck near Houston
September 8, 2010 9:52 am

Leon Brozyna said:
And suddenly Igor forms just south of Cape Verde islands. Sounds like a bad horror film.
On the pronunciation of “Igor”:
Igor: Dr. Frankenstein…
Dr. Frederick Frankenstein: “Fronkensteen.”
Igor: You’re putting me on.
Dr. Frederick Frankenstein: No, it’s pronounced “Fronkensteen.”
Igor: Do you also say “Froaderick”?
Dr. Frederick Frankenstein: No… “Frederick.”
Igor: Well, why isn’t it “Froaderick Fronkensteen”?
Dr. Frederick Frankenstein: It isn’t; it’s “Frederick Fronkensteen.”
Igor: I see.
Dr. Frederick Frankenstein: You must be Igor.
[He pronounces it ee-gor]
Igor: No, it’s pronounced “eye-gor.”
Dr. Frederick Frankenstein: But they told me it was “ee-gor.”
Igor: Well, they were wrong then, weren’t they?
Young Frankenstein (1974)

Dave in Delaware
September 8, 2010 10:23 am

Interesting discussion on many levels, including the thoughts on heat extraction from the ocean and/ or mixing of surface and near sub surface waters.
I bet the ARGO floats have been bobbed around in the Atlantic and Pacific by these huge storms. Since the floats periodically dip down to measure deeper waters, perhaps there is actual temperature data, profiling the surface and sub surface before after and possibly during a storm.
Anyone know if the ARGO folk have looked at this or posted anything?
If not – some enterprising researcher could probably score themselves a nice publication for that analysis.

George E. Smith
September 8, 2010 10:50 am

“”” George E. Smith says:
September 3, 2010 at 2:42 pm
So we have Earl kicks up a hell of a fuss down there in the Carribean, and then turns into a fizzer of sorts as it gets up north. But notice that Fiona and her followers also seem to have gone phut !
One might conjecture; sans models or data; that Earl did a number on the SSTs in that particular Atlantic track; and sucked the life out of anybody following in his footsteps.
so maybe a lot of wannabe Hurricans just got stillborn on account of Earl’s Carribean enthusiasm.
So how long should we have to wait for another monster to get going ? “”””
Sometimes I wonder why I bother to post this stuff; it apparently doesn’t get read by anybody besides Chasmod.
But people would rather believe that Hurricanes stir up the ocean down to the bottom and bring up cold waters from the deep. So why is it that the same fishes that were there before the Hurricane passed through are still there after it passes; and haven’t been replaced by deep ocean denizens. I’m sure it is possible that hurricanes can steal heat from about the same volume of ocean that the sun directly heats; but that still is just basically surface waters; in the overall scheme of things.
Roy Spencer has several times posted the amount of energy in a Category Three hurricane; that it sucks up out of the ocean.
As for what all that latent heat does in warming the atmosphere (above the water); it doesn’t do anything. Can’t you understand that that “heat” got used up converting all those megatonnes of sea water to atmospheric water vapor; so there isn’t any left over to heat the lower atmosphere. And that lighter than air water vapor rises up, and forms that big cloud swirling mass; and at that time (that the cloud forms) the latent heat is returned to the upper atmosphere to warm the upper atmosphere which ultimately radiates much of it to space.

Caleb
September 8, 2010 10:56 am

My own sense is that the cooling left behind a hurricane is less due to upwelling, and more due to the actual removal of heat from the surface waters, than most people suspect.
It seems that creating an upwelling involves overcoming quite an inertia, especially when you factor in the reality that the eye of a hurricane is seldom stationary, and is usually chugging along at ten mph or so. It is difficult to conceive the engineering of a mobile upwelling, moving along at ten mph. Although a hurricane’s low pressure may be enough to lift the surface of the sea ten to twenty feet, the surface then drops ten to twenty feet after the storm passes, without involving any down-welling I’ve ever heard of.
Not that some upwelling doesn’t occur. I just don’t think it is the major reason the sea-surface cools. The real reason, I think, is that the surface water is churned to an unbelievable degree. Imagine the churning of a white cap, when the wind is only twenty-five mph, and then multiply it to a degree where the entire surface of the sea is white, and the air is filled with spray. I have only experienced winds up around fifty in the open sea. That’s crazy enough for me, but I have read descriptions of the sea in hurricanes, and my conclusion is that the boundary between water and air is indistinct, and the churning is a marvelous transfer-system, when it comes to moving warmth and moisture from the sea to the air.
This moist warmth is then updrafted by stupendous thermals right up to the tropopause, releasing huge amounts of latent energy as it rises. Up at the tropopause there is very little atmosphere left to have any “greenhouse effect,” so the heat could be easily lost to outer space. In this manner a hurricane could act as a sort of safety-valve, venting excess heat off into outer space.
But here is where my ideas run into a problem: The satellites I know about don’t look down on a hurricane and see hot things. Instead they see some of the coldest cloud-tops on earth, with temperatures lower than a hundred below zero, (F).
Does a gadget exist that measures how much heat hurricanes lose to outer space?

September 8, 2010 11:05 am

Chuck near Houston says:
September 8, 2010 at 9:52 am
Misspelled, it’s EE-GORE , the servant of the Prince of Darkness. (A.K.A. XXX massages seeking prophet)

wayne
September 8, 2010 11:15 am

Tom in Florida says:
September 8, 2010 at 5:37 am
The next question would be : What happens to the air that has been warmed by the release of the latent heat and where does it go?

Would think it’s mostly gone by the time the hurricane passes. Much warmer than normal air at that altitude is radiating slightly more than half (52-54% at that altitude) to space and the remaining back down. That part to space is the overall cooling that hurricanes do. The part directed downward just nullify the initial cooling that left the surface maintaining the evaporation. For every cooling there is a warming, for every warming there is cooling. You can also say hurricanes warm the universe more than normal from the earth.
That small portion of warmth left at that high altitude I don’t know exactly what happens to it after the storm passes, and the effects. Maybe some with some meteorology knowledge can clue both of us on that.

frederik wisse
September 8, 2010 11:36 am

Could a scientist tell us how an infrared picture of a hurricane is looking taken from space ? The color to my humble belief would identify the heat radiated into space !
Are the hurricanes in reality the airconditioners of planet earth ?

September 8, 2010 11:50 am

wayne says:
September 8, 2010 at 11:15 am
It rains! Obvious!

John F. Hultquist
September 8, 2010 12:09 pm

Many of the comments here concern the warmth being carried out of the ocean, into the northward spiraling storms, and into the upper atmosphere in the Northern Latitudes. A not insignificant aspect of this process is that the subsolar point (where the vertical ray of the sun hits) is now at the latitude where these storms (mostly) begin. As I write this, it is about 5.5 degrees N. Lat., heading toward the Equator and points south. Thus, the ocean during the peak of the hurricane season is also at the peak of its intense solar radiation. Until early October this won’t change very much.
Follow the declination here:
http://www.jgiesen.de/deceot/

dp
September 8, 2010 12:15 pm

George said:
“As for what all that latent heat does in warming the atmosphere (above the water); it doesn’t do anything. Can’t you understand that that “heat” got used up converting all those megatonnes of sea water to atmospheric water vapor; so there isn’t any left over to heat the lower atmosphere. And that lighter than air water vapor rises up, and forms that big cloud swirling mass; and at that time (that the cloud forms) the latent heat is returned to the upper atmosphere to warm the upper atmosphere which ultimately radiates much of it to space.”
If warmed air is an isotropic radiator, and I have no reason to think it isn’t, why would more than just over half of that radiation find it’s way to space? Obviously at some point all excess heat goes into space, but we’re talking about a much shorter time frame here.

PJB
September 8, 2010 12:37 pm

Why does blowing across the top of a hot cup of coffee cool the coffee?
Evaporation. SSTs are high before the wind affects the top 20 meters or so as that is the size of the swells in a cat 3+ hurricane.
Your coffee is only cold on the very top and if you stop blowing on it, it warms back up until the whole cup has cooled.

wayne
September 8, 2010 12:41 pm

wayne says:
September 8, 2010 at 11:15 am
It rains! Obvious!

Of course, of couse. The Rain! ☺
I was really meaning if you could look at a small cell map of the AMSU of, let’s say, 150 mb level would you also see a slight warming tracking after the hurricane passes? That energy increase would be totally dwarfed by the loss in ocean water but does that appear also. Just a scientific curiosity. Guess Dr. Spencer would know. Might actually show a cooling also, dunno.

hotrod (Larry L)
September 8, 2010 12:58 pm

I have only experienced winds up around fifty in the open sea. That’s crazy enough for me, but I have read descriptions of the sea in hurricanes, and my conclusion is that the boundary between water and air is indistinct, and the churning is a marvelous transfer-system, when it comes to moving warmth and moisture from the sea to the air.

Yes it becomes very indistinct. I experienced a super typhoon on board a U.S. Navy ship in the 1970’s (Typhoon Amy off Guam Mariana Islands 1971) which had winds up in the 140+ (175 mph) knot range for a while.
http://en.wikipedia.org/wiki/1971_Pacific_typhoon_season
I stood a watch in the ships bridge when winds were 120 knots and at that time the sea surface was just a gray haze and looked much like a ground blizzard. You could not see the water at all just the blowing spray off the wave tops. We had a few waves put green water on our open bridge windows 3 levels above the main deck.
After the typhoon I talked to some of the boat sailors (submariners) who also went out of port during that storm, and they told me there was extreme turbulence at over 100 feet depth and they had to go deeper than that to avoid severe pitching and rolling from the wave action above.
In short a hurricane or typhoon causes substantial mixing down to 100- 200 ft depth based on what I was told by the boat sailors.
The huge surface area of all the sea spray plus high winds can transfer a staggering amount of heat energy from the water to the air, in the form of evaporated water, and the cooling effect on the sea water surface is very substantial.
All that water gets lifted to near the stratisphere by the storm where it can radiate heat away to the sky at the cloud tops as even more heat is released as the water vapor freezes out to ice crystals. Then that ice descends and melts to produce a very cold rain as the cycle continues.
Larry

George E. Smith
September 8, 2010 1:15 pm

“”” hotrod (Larry L) says:
September 8, 2010 at 12:58 pm
……………………….
After the typhoon I talked to some of the boat sailors (submariners) who also went out of port during that storm, and they told me there was extreme turbulence at over 100 feet depth and they had to go deeper than that to avoid severe pitching and rolling from the wave action above.
In short a hurricane or typhoon causes substantial mixing down to 100- 200 ft depth based on what I was told by the boat sailors. “””
Well I wouldn’t confuse severe turbulence at 100 ft depth with the notion that waters at that depth are being exchanged with surface waters.
Water is not incompressible; no matter what they tell you; so when you have big waves; 50-100 ft or more on top of deep ocean water, the pressure transisents of those waves passing overhead is of course going to create havoc at 1-200 ft below, in that deep water. That doesn’t mean that deep water is going to come up to the top; along with your submariner friends.
I’ve done a whole lot of diving (free diving) in waves that are approaching the break line coming into a beach; so that the wave peak to peak height was of the order of half the average depth; and down at the bottom, you certainly feel the pressure of the wave peak going over the top; but I’ve never been sucked up to the surface; just rocked in and out along the bottom.
If there was large mass transport of deep water to the surface in severe storms it would probably kill much of the sea life being tossed around like that.

wayne
September 8, 2010 1:17 pm

Enneagram:
September 8, 2010 at 11:50 am
Darn, sent that last one to myself, should have tagged to you.

George E. Smith
September 8, 2010 1:40 pm

“”” Caleb says:
September 8, 2010 at 10:56 am
My own sense is that the cooling left behind a hurricane is less due to upwelling, and more due to the actual removal of heat from the surface waters, than most people suspect.
………………………
But here is where my ideas run into a problem: The satellites I know about don’t look down on a hurricane and see hot things. Instead they see some of the coldest cloud-tops on earth, with temperatures lower than a hundred below zero, (F).
Well Caleb; the problem with using the word “heat” as a noun; instead of a verb; denoting a process, is that our imagination then runs amok; and “heat” becomes “hot” , which is at loggerheads with your sub zero cloud tops.
This image is compounded by the totally fraudulent “laboratory” demonstrations where they take two cylindrs of air; drop a small chunk of dry ince in one, to give it more CO2 ( a very popular “doubling” technique); and then put an incandescent “HEAT” lamp nearby so you can see that the one with the “doubled” CO2 gets HOTTER than the other one.
One problem is that there aren’t a whole lot of INCANDESCENT HEAT LAMPS pointing up in the air; out in the wilds.
The HEAT SOURCE that Mother Gaia uses in HER LABORATORY DEMONSTRATION is like a typical garden brick that has been sitting in the shade and is at a Temperature of 288 Kelvins or +15 deg C. That is the typical source of LWIR radiation that is heating the atmosphere by way of the green house gas capture process.
Well of course we all know there is conduction and convection from the surface going on as well as evaporation; but from the radiation point of view the earth does NOT look like a 2800 Kelvin Incandescent lamp; which probably has its spectral peak at somethign like one Micron rather than 10 microns; and since it is 10 times the Temeprature of a typical garden brick it is radiating 10,000 times the 390 W/m^2 that Trenberth uses for his typical earth surface radiant heater.
Humans DO NOT sense 10.1 micron peak wavelength thermal spectrum radiation as being “HEAT”; in fact we don’t sense it at all as anything. We have to go out of our way with cooled detectors to even detect such radiation at all.
But those “Science guy type” TV frauds lie to us and convince us that their fake experiment is demonstrating the greenhouse effect. It isn’t; it is demonstrating a completely different effect with a completely different spectrum from a completely different artificial soure of radiation that human skin DOES detect as being what WE call HEAT.
Nobody ever suffereed from heat stroke in the middle of a category five Hurricane; it gets bloody cold in one of those things; but it is being fed by thermal energy from the warm surface waters of the ocean under the right atmospheric conditions.

George E. Smith
September 8, 2010 1:44 pm

I guess the Censorbot doesn’t understand Australian adjectives; so it is sitting on my last post. In any case here’s the legal disclaimer. In referring to the “fraudulent “Science guy” types” I was simply using that term as a descriptor; and was in no way pointing personally at that chap; whoever he is, that goes by the name of “the science guy” somewhere or other. Dunno where since I have never seen his act.

September 8, 2010 1:52 pm

Cooler Atlantic makes cooler Arctic.

cassandraclub
September 8, 2010 2:07 pm

Kewl post

hotrod (Larry L)
September 8, 2010 3:03 pm

This paper seems to address the wave mixing issue — perhaps some of you might care to comment on its content.
http://www.mmm.ucar.edu/people/sullivan/talks/papers/aha.pdf
Larry

Mark Cooper
September 8, 2010 3:14 pm

The surface water layer will have significantly reduced density due to the rain. It may be that the surface density is lower than the warmer but saltier water below, thus inhibiting upwelling and mixing of layers and delaying surface water temperature increase.

Paul Bahlin
September 8, 2010 5:08 pm

If I remember correctly, wind acting on the surface of the ocean creates a mean current that is at right angles to the wind (known as Ekman spiral). Consider then, the wind circulation at the surface of a hurricane. It’s a circle and the mean water flow from the circulation is radially outward. Compound this with the fact that this outward flow is downhill due to the low pressure at its center and you get a giant sucking straw at the center of the hurricane that is pulling water up from below, spewing it outward and down.
It seems to me that the total effect is sort of like a moving toroidal pump that is circulating cold water up from below to be replaced with water flowing downwards at the perimeter of the circulation. It also seems that this could be working on far more than near surface water.
I wonder if there isn’t also a nutrient track that would be detectable in the wake due to the nutrient rich deep water being pulled up into the relatively low nutrient upper layer. The nutrient levels might even serve as a proxy that would give you a clue how deep this flow is operating.

Paul Bahlin
September 8, 2010 5:13 pm

Another point to consider in the discussion about where does all the heat energy go is the whole kinetic energy balance. A hurricane is moving a massive volume of water vapor (and other gas) at high speed. Heat energy is not only being radiated it is being converted to kinetic energy.

Caleb
September 8, 2010 5:30 pm

RE: hotrod (Larry L) Thanks for the first-hand description. In many ways I learn more from eye-witnesses than anyone or anything else.
RE: George E Smith Thanks for responding. Appreciate the fodder for my hungry brain.

Andrew
September 8, 2010 5:55 pm

“Note also the large and growing La Niña off the west coast of South America. It’s turning deep purple and on to black. Way cool. ”
I’m having a seriously hard time believing the temps off the west coast of Central/South America. There’s not even a single pixel’s difference from black to orange in some spots. Unless there’s some sort of major upwelling current right there that doesn’t mix to any meaningful extent with the waters to the NE I’d have to wonder about the validity of the data.
REPLY: That is generally the major characteristic of a La Nina – Mike

sky
September 8, 2010 5:58 pm

hotrod (Larry L) says:
September 8, 2010 at 3:03 pm
The paper you reference is entirely the product of numerical modeling. As the authors state: “The above predictions need to be validated against observations in high-wind conditions.” While I concur, on the basis of observations, that plunging crests from hurricane-driven waves are effective means of mixing, the depth of that effect is on the order of a few meters. This should not be confused with the depth to which wave-pressure variations are felt, which may extend downward to ~250 feet with typical 10-second waves raised by hurricanes. In deep water, the pressure becomes effectively extinct at half the wavelength, which is given in feet by 5.12T^2, where T is the wave period.

Editor
September 8, 2010 6:12 pm

Peter H says:
September 8, 2010 at 4:16 am (Edit)
“Yes, I think it’s reasonable to say they might have cooled the sea surface.
But what about at greater depths?”
Generally speaking, you can expect to see mixing of the water column under a hurricane track that is as least as deep as the maximum wave amplitude generated by the storm. I heard that Earl was generating 48 foot waves, which means that given most of the heat content in the oceans is in the top 15 meters of the water column, that the cooling tracks generated in sea surface temp measurements are pretty homogenous for the water column. On the other hand, mixing can also cause anomalously warm surface waters to be cooled simply by dilution with deeper waters they are mixed with, without transporting most of that heat to the upper atmosphere in the cyclonic system.

September 8, 2010 6:38 pm

Andrew says:
September 8, 2010 at 5:55 pm
Are you single?….If you are not then you have all the data for a total understanding of La Niña (The Girl). 🙂

wayne
September 8, 2010 6:55 pm

George E. Smith says:
September 8, 2010 at 10:50 am
Sometimes I wonder why I bother to post this stuff; it apparently doesn’t get read by anybody besides Chasmod.
But people would rather believe that Hurricanes stir up the ocean down to the bottom and bring up cold waters from the deep. So why is it that the same fishes that were there before the Hurricane passed through are still there after it passes; and haven’t been replaced by deep ocean denizens. I’m sure it is possible that hurricanes can steal heat from about the same volume of ocean that the sun directly heats; but that still is just basically surface waters; in the overall scheme of things.

Your being read and I agree that it’s only the top x meters that gets actually cooled. If there is deeper water slightly warmer than this new cool layer then it will equalize over time.

wayne
September 8, 2010 7:10 pm

Mark Cooper says:
September 8, 2010 at 3:14 pm
“The surface water layer will have significantly reduced density due to the rain. It may be that the surface density is lower than the warmer but saltier water below, thus inhibiting upwelling and mixing of layers and delaying surface water temperature increase.”
Guess you think all of that moisture rained by a hurricane is coming strictly from the moist atmosphere and not the ocean below. I view it the other way around and upon evaporation of a huge amount of seawater occurring below a hurricane the ocean salinity is being first increased, rising to heights, and raining down thus nullifying that same opposite effect. Decrease salinity, I can’t see it. It’s easy to just ignore the very opposite side of the action being mentioned.

Jaydayrock
September 8, 2010 7:20 pm

Hillo, hello, hello?? Do you live near Ottawa? Are you concerned about chemtrails? Can we work together?
Thanks,
Jaydayrock
[Reply: chemtrails discussions not allowed here. ~dbs, mod.]

hotrod (Larry L)
September 8, 2010 8:09 pm

Wave motion in the oceans occurs on all scales and depths it is not just surface waves, that need to be considered. Large surface waves could interact with deeper waves which exist below the surface.
The “mixed layer” of the ocean extends to about 1500 ft depth, and exists because various mechanism thoroughly mix that top layer of water, so that it has relatively uniform temperature and relatively small density differences.
http://www.villasmunta.it/oceanografia/the_three.htm
http://web5.cns.utexas.edu/news/2008/06/
http://my.opera.com/nielsol/blog/2010/07/17/internal-ocean-water-mixing
If you consider all these effects it is not at all unreasonable that there are large vertical displacements induced by very large surface waves and other effects like salinity, density due to thermal cooling by evaporation, and salinity changes due to either dilution from rainfall or evaporation of water from warm water where little rainfall is present.
As noted above a hurricane or typhoon would create a very complex environment due to its presence. Plunging surface waves when breaking would impart downward momentum as the crest breaks. The breaking action would also create non-uniform density due to aeration of the water, as this plunging breaker drives air bubbles deep below the surface. In the area near the eye wall you have very high speed winds evaporating water from the sea surface both cooling it and increasing its salinity. Add to that the barometric pressure difference tending to pull water up in the eye of the storm and the wind driven surge on the “right hand side” of the storm would create conditions that would be likely in my view to cause over turning of the surface water as it attempts to find equalibrium.
The high winds would first rapidly cool the surface layer and evaporate water from it increasing its salinity, upsetting the relatively stable mixed layer with a high density surface layer over a lighter warmer pool of water. Add in a little wave action to provide initial vertical motion and the density difference would provide the rest of the energy to drive the sea water equivalent of a down burst.
In areas where you have torrential rain fall of nearly fresh water falling on the surface of the water you also have to consider the density changes due to the cooling of the rain as it falls from high altitudes. That cold fresh water, mixed with a little surface salt water could also create an area of density instability which could over turn some of the surface waters bringing warm water up from below and the cooler mixed layer on the surface due to wind and rain plunging down until it finds equilibrium.
I am aware that the first paper was “only” a numerical simulation, but I have a lot more faith in the empirical evidence of an submarine sailor getting tossed about in his boat well below the surface than I do assertions that very large waves cannot cause significant mixing below the surface.
Obviously it would be nice to find a study where someone actually did measurements of turbulent mixing during a major wind event but so far the pickings seem to be thin with regard to actual physical data in that regard.
Larry

savethesharks
September 8, 2010 8:49 pm

This has proven to be a fascinating thread. My eyes are tired staring at my laptop LOL.
But thanks to George E. Smith, Wade, DP, Hotrod, Mike Lorrey, Caleb and others for the cool discussion.
Chris

savethesharks
September 8, 2010 8:50 pm

Ha. I said “Wade” I meant “Wayne.”
Tired eyes….and tired brain.
Chris

wayne
September 9, 2010 1:40 am

savethesharks says:
September 8, 2010 at 8:50 pm
Tired eyes….and tired brain.
Chris

Mine too.
And Anthony, thanks for an interesting and relevant article!
hotrod (Larry L):
September 8, 2010 at 8:09 pm

Good description!
I agree on the more long-term deep wave mixing effects but I’m going off a link given a few articles ago to a great paper showing satellite IR tracks of hurricanes with temp scales intact. These hurricanes were tracking behind at about -5ºC and I just don’t think if the depth of vertical mixing were many hundreds of meters THAT much energy is moved to space. Now that would be one whole lot of joules! (and would take a long, long time to warm back, multi-years) That’s what I meant about the top few x meters, speaking just on the amount of energy that one hurricane could possibly move vertically and out to space.
Now the jostling back and forth, locally up and down, much deeper to hundreds of meters as the roots of the waves pass, that make sensible and I’ve read correct in what you were saying.
I had always though that the deep mixing was by currents, slow and persistent movers, mainly north and south in the Atlantic and Pacific specifically, and the moon, picking up the entire ocean a few millimeters and then letting it go, twice a day, every day, that doing the primarily east-west movements. It’s the shallower sloping continental shelves where the main mixing would occur. Water pulled up the slope, released to move back down. Guess if you computed the total amount of water moved daily by the moon’s gravity it would so totally dwarfs that moved by a mere single hurricane, but, hurricanes we can actually see in live action and just look what they alone can do! But the tides and currents are so slow and gradual that if you don’t live right on the coast and the land slopes are shallow you never notice them at all.

September 9, 2010 5:01 am

Paul Birch says:
September 8, 2010 at 6:37 am
“I can understand why a following hurricane might be weakened by cooler waters, but I don’t see why this would slow it. Repulsion between the two vortices (if they are rotating the same way) might do it.”
I think I’ve got that the wrong way round. Vortices of the same sense attract. So the following hurricane ought to speed up, not slow down.

Lee Kington
Editor
September 9, 2010 5:23 am

Paul Birch says:
September 8, 2010 at 6:37 am
I think I’ve got that the wrong way round. Vortices of the same sense attract. So the following hurricane ought to speed up, not slow down.

As adjacent air?
Adjacent air

Charles Wilson
September 9, 2010 7:11 am

WATCH OUT. East Coast ! (Again)
http://www.osdpd.noaa.gov/ml/air/index.html — look at the Aerosol Daily !
Saharan Dust is going SOUTH again. Like just before Earl.
Remember, the El Nino made this a SUPER-season for Hurricanes – – in water temp.
BUT then also made Saharan Dust Storms, which Killed them – – just like 1998. It happens when the El Nino is TOO strong.
This year, we’ve had dust as far as the WESTERN Caribbean, most days ( ! ) (see aerosol Monthly)

Gail Combs
September 9, 2010 7:42 am

“”” George E. Smith says:
…..Sometimes I wonder why I bother to post this stuff; it apparently doesn’t get read by anybody besides Chasmod….”
Oh, it gets read. I always pay special attention to what you have to say.

September 9, 2010 8:53 am

Lee Kington says:
September 9, 2010 at 5:23 am
Paul Birch says: “I think I’ve got that the wrong way round. Vortices of the same sense attract. So the following hurricane ought to speed up, not slow down. ”
“As adjacent air?”
Bernoulli effect. If the air in the vortices is trying to circulate past each other, as in your diagram (vortices have same sense), it is squeezed into a narrower channel, so goes faster, so sucks harder, causing the vortices to orbit each other. Whereas if the air is going the same way (vortices have opposite sense) it can spread out more, going more slowly, thus increasing the pressure and causing the vortices to repel each other. I think that’s roughly the mechanism. I may not have got it quite right, though – I’m not entirely happy with it.

September 9, 2010 9:19 am

Bob Tisdale says:
September 8, 2010 at 7:25 am
I wanted to call your attention to the graphs you show in your website, as in:
http://i51.tinypic.com/osgvop.jpg
NINO3.4 SST Anomaly
Monthly Change = -0.22 deg C
it appears only a difference of about 1.5 degrees between the peak of 1998 and 2010, what seems to be a most convenient GWR graph, as the real difference between the two Ninos, where I live , in the 1+2 area, the maximum temperature in 1998 it was 39 C, while this year was 29 C, a difference of TEN degrees centigrade LOWER than in the 98 El Nino
How do you explain that? or is it Statistics Magic?

PhilJourdan
September 9, 2010 10:16 am

Chuck near Houston says:
September 8, 2010 at 9:52 am

Stole my line! 😉 I cannot understand why all the weather forecasters still call it “ee”gor instead of “eye”gore!

George E. Smith
September 9, 2010 10:54 am

Concerning this discussion of hurricanes cooling the ocean surface; and turbulent mixing with the cool deep ocean waters.
Don’t assume that I think those deep waters just sit there forever. Even due to just tidal movements; the whole oceans have to be in a constant non-equilibrium condition; and probably at all scales.
In the most simple model of waves on water, pure “gravity waves” require nothing more than gravity acting constantly downward on each water molecule as it is displaced up and down affected by just gravity and local buoyancy to try and return to a level surface equilibrium state.
So although the waves are moving along the surface; maybe at 400 miles per hour even, the water isn’t moving along the surface; it stays in the same place. So a wave coming over to Califonia from Hawaii, is not bringing any Hawaiian water with it.
A more accurate physical description of water waves will show that in fairly ordinary water waves, an individual molecule actually runs around in a roughly circular orbit (in the plane of the wave travel direction); so even though on average the molecule doesn’t go anywhere; instantaneously it is moving in this orbital motion. And as you might expect, the amplitude of that circle depends ont he amplitude of the wave. So that alone means there is a vertical mixing right at the surface layer; but this is very much smaller amplitude than the total depth at which the pressure waves of the storm can be sensed down deep.
It is easy to relax into a simpler one dimensional model of the ocean, and think of it as simply a stack of water layers; each with a different temperature. Waters that are tens to a few hundred metres are still transparent to some parts of the solar spectrum so that allows a lot of energy to be deposited many tens of metres down, and that should cause local heating, and expansion, resulting in a vertical convective gradient. But in a one dimensional view, why would anything really move. Well of course the ocean is not nice and stably one dimensional, and somewhere that upward convection will manifest itself and covey the solar warmed water back to the surface; where evaporation can probably put some of it into the atmosphere. Of course surface waters that have alread cooled for some reason will dive to make up for the vertical convection. Kirchoff’s Law has to be obeyed or the water would stack up somewhere. When you add in the tidal driver due to the rotating earth, then it is obvious that the oceans can’t settle down to any stable one dimensional state.
I’m not a cosmologist; but I am under the impression that Sir James Jeans did a famous calculation wherein he proved that any large enough amount of matter (gaseous mass) that is all attracting itself gravitationally must become unstable and undergo gravitational collapse; which is how star formation gets going in the first place. But note that that collapse is NOT well behaved, squishing everything into a single massive black hole; the large mass breaks up into chunks; which individually collapse.
I suspect that somewhere in there is the concept of the velocity of sound waves; and that material can only move under the drive of its self gravity, at a certain rate; so information about the collapse cannot be transmitted across the space; to tell those clumps “over there” that they are out of step. It is that finite velocity of propagation of information that stops the whole thing from dancing like the Rocketttes.
Yeah I know it’s a lame image; but I don’t have any colored sands for my beach stick to draw with.
That Jeans chap sure got around. In addition to an early exposition of the radiation spectrum of heated bodies (pre-Planck) he also did a classic derivation of the low temperature specific heat of solids. and then there is that cosmic collapse exposition. All I can remember about the derivation of the specific heats of solids at low temperature, is that you have to calculate the number of degrees of freedom in some mass of material (probably a mole) and assigns some KT or similar energy to each. Somewhere in the process, you get entangled with a square root of some expression; which would be easy to simplify; if you just replaced one of the factors in there with unity (1). Then it simplifies to somethign recognizable. The only problem is that that factor which you made equal to 1 is Avogadro’s number; 6.023 .10^23 That’s some approximation; even for Dr James Hansen.
Well the expression of which this pesky Avogadro’s number is a nuisance factor happens to contain factorial of Avogadros’ number. Now all of a sudden 1 is a rather reasonable value to use to get rid of that annoyance. Other than that, I remember nothing at all about the Jeans derivation.
But back to the water fights; the local turbulences kicked up in Hurricanes are certainly going to do some mixing; but suppose that we declare that that mixing with deeper layers is where the cold water came from; and not the latent heat of evaporation escape. Well that means that there must be a lot of suddenly warmer deep water that was transported to the depths by that same mixing.
So Ok all you Google sleuth’s; find us some peer reviewed experimentally measured data peper(s) on the appearance of deep layers of abnormally warm water that can be found in the depths of a big hurricane track; because if mixing is the source of the cold surface waters; then most of the warm water must still be there in the depths. If you are not aware of this then remember that you first heard about it here at WUWT.
No I’m not going to hold my breath while somebody finds a reference to the post hurricane deep warm water tracks.
My money is still on the Latent heat of evaporation about 545 Cal per gram of it; I( really must convert that number to Joules some day).

sky
September 9, 2010 3:46 pm

hotrod (Larry L) says:
September 8, 2010 at 8:09 pm
Ocean waves propagating under the influence of gravity produce water particle motions that are inherently coherent and irrotational (i.e., particle orientation is invariant throughout the orbit). Thus, unlike shear currents, they are intrinsically a poor mechanism for any turbulent mixing. Such gravity waves require a density discontinuity for propagation. The coherent motions of internal gravity waves, which are very slow to begin with, are consequently restricted to the vicinity of a sharp pycnocline. The only waves of practical consequence found at ALL depths of the oceans are the forced soli-lunar tides, whose motions are also coherent.
Turbulent mixing is largely a wind-driven process, with wave-current interactions being at best a second-order effect. The well-mixed, oxygenated layer as firmly recognized by oceanographers (see, e.g., de Boyer Montegut et al.) seldom exceeds 100m and is much shallower in tropical seas, where cyclones originate.
Although empirical data on hurricane-produced mixing are tough to find (the Navy seldom releases submarine-gathered data), some offshore platform data that I’ve seen indicates that at 200m and below the effects of hurricanes are virtually undetected. Don’t become enraptured by trendy ideas published by academics that have more to to do with the climate-change gravy train than with proven real-world physics.