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:
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.
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
HEAT PUMP!
now we are getting somewhere!
And suddenly Igor forms just south of Cape Verde islands. Sounds like a bad horror film.
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?
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
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
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.
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?
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.
The cooling path:
http://weather.unisys.com/surface/sst_anom.html
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
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.
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.
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.
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.
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.
Bubbagyro – don’t you suppose a cat5 hurricane might just be whipping any near-surface thermoclines to a frothy uniformity?
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 🙂
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?
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)
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 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.
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?
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)
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.