Undersea Volcanic Eruption In Tonga

Guest post by Steven Goddard


The Washington Post reports today:

An undersea volcano erupts off the coast of Tonga, tossing clouds of smoke, steam and ash thousands of feet (meters) into the sky above the South Pacific ocean, Tuesday, March 17, 2009. The eruption was at sea about 6 miles (10 kilometers) from the southwest coast of the main island of Tongatapu an area where up to 36 undersea volcanoes are clustered

Besides the unusual feet to meters conversion in the quote above, I found it interesting because the SST maps show a warm anomaly in that region, and extending off to the east. Is that anomaly a result or coincidence?



How much influence do volcanoes have on local climates?

We know that the Antarctic Peninsula (advertised as the fastest warming place on the planet) is a volcanic chain which has seen recent activity.

Noted Antarctic expert Eric Steig tells us that Volcanoes under the ice can’t affect climate on the surface, 2 miles above! This is indeed true and interesting, because CO2 on the surface reportedly can affect the melting of the basal ice, two miles below.

According to some of the best AGW minds, increases of 0.0001 atmospheric CO2 concentration may be more powerful at affecting localized micro-climates than are 2000 degree volcanoes.

In another volcanically active area, the Gakkel Ridge, which was shown to have eruptions last year, the possibility also exists for localized warming. Here is a schematic of the Gakkel Ridge sea floor:


From the National Science Foundation - Click for larger image

However in that case there is the claim by oceanographic experts that it is impossible for the sea ice above to be affected due to stratifed water layers and thus making the released heat “unable to communicate” to the surface.

Perhaps that is true, but does that stratification remain in a steady state? And is such an inability to “communicate” heat from the depths a feature of our oceans globally?


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Charles Darwin proposed that coral atolls [e.g., Tonga] were formed by extinct undersea volcanoes. As the extinct volcanic cone gradually subsided, coral built on it and formed the atoll: click [scroll to the last paragraph, p. 232.]
There was much dispute among scientists about Darwin’s hypothesis, but eventually Darwin was proved right. So the current volcanic activity may eventually bring about a new coral atoll.
The sea level isn’t currently rising, and when it did rise in the recent past, the increase was simply part of a natural ebb and flow. As can be seen in this picture, the sea level has not changed much from the mid-1800’s. So the argument that AGW is causing the sea level to rise is falsified.


Note the cool La Nina-like conditions milling about around the equator just off the West coast of South America


Where there is smoke there is fire… where there is steam there is heat!!! I would think that the super heated steam would have much more effect than the CO2 contained in the “smoke”.


What is that anomaly to the east of Argentina?

I found it interesting because the SST maps show a warm anomaly in that region, and extending off to the east. Is that anomaly a result or coincidence?

Quite some time ago I developed an interest in submarine volcanic activity. At the time I had, and still have, several questions regarding their effect on…
1) Sea temperatures
2) Sequestered CO2 & CH4
3) New volcanic emissions
Logic tells me that the depth of a volcano would alter its impact. Some say they have no impact. I can see that as true for a volcano at great depth. Certainly one in the Marianas Trench over 30,000 feet deep would have minimal to no effect. However, at shallower depths they must.
The problem of course is that there are 10,000 or more submarine volcanoes, we don’t have an accurate inventory, nor are they really monitored with exception of a few.
With the oceans playing a major role in the earth’s climate it would seem that man needs a greater understanding of them inclusive of submarine volcanic activity. Currently we have about 70 major (VEI 4 or larger) land based volcano eruptions per century.
http://penoflight.com/climatebuzz/Misc/MajorVol1.jpg (data points are at 50 yr increments.)
It would stand to reason that there should have been about 600 – 700 major ( VEI 4 or larger ) submarine volcano eruptions last century, if not more.

Barry L.

Underwater volcano’s could be the next hot topic.
Underwater volcanos
From a report on Hydrothermal vents, a quote:
Temperature and velocity measurements
obtained within a few centimeters of focused vent orifices yield
power outputs which range from less than 1 to nearly 100 MW,


So maybe these ocean temperature maps may serve a greater purpose…detecting imminent volcanic activity?

Phillip Bratby

OT Anthony, but have you seen “Melting Antarctic Ice Part of Natural Cycle” at http://theresilientearth.com/?q=content/melting-antarctic-ice-part-natural-cycle?

Alan the Brit

I would have thought that as heat rises, or at least it used to, although not necessarily evenly & linearly the heat from a volcanic sub-surface eruption would find its way upwards some where or other via convection currents! I must say I have not heard of heat sinking before but I’m always willing to learn something new every day!
O/T, I watched a programme on the History channel a few weeks ago now, it was a repeat of an Horizon programme about freak waves & was a little old, early 2004-5 I’m guessing as I missed the first 5 mins thro lunch & the last 5 mins because my wife made me go shopping, huh! An expert from where else but the Met Office was filmed saying that his computer model showed that these freak waves occurred only once in every 10,000 years! Yet further study by others later in the programme showed that these 1/10,000 year occurrences were actually happening pretty much regular as clockwork in the right ocean current/wind conditions! (I daresay they sneaked in a touch of global warming at the end) A sort of over blown wind over tide scenario if you like. So experts aren’t always right to trust their computer models then?


I was intrigued by Smokey’s post and the link to the 1800’s sea level mark. This may not be conclusive because the tectonic plates also rise and fall, right? As I understand it the Indian plate is pushing up above the Eurasian plate (from memory, probably wrong) — does this mean that Bangladesh will rise out of the sea and we don’t need to worry about all those millions of people inundated by rising water? Inquiring numbskulls want to know :).


Is not that smoke and steam the undersea “communicating” with the upper layers?


Noted Antarctic expert Eric Steig tells us that Volcanoes under the ice can’t affect climate on the surface, 2 miles above! This is indeed true and interesting, because CO2 on the surface reportedly can affect the melting of the basal ice, two miles below.
Is this anything like being told that the cold phase of the PDO can cancel out AGW for up to 30 years, but the warm phase of the PDO has absolutely no affect on AGW.

Steve: Based on the NCDC SST anomaly animation, it appears your hotspot may be coincidental weather noise. Unfortunately, this animation is lagging by about a week. We’ll just have to keep an eye on it.

Johnny Honda

So, we have the big question:
What heats the ocean up more:
– Air is 0.002658 °C warmer than usual
– Gigantic volcanic eruption


Tonga; 21°08′S 175°12′W
This is the closest buoy find that
see the 400 m depth

alexandriu doru

The mean geothermal flux on earth is 60 mW/m^2;
The mean solar flux on earth is 240W/m^2.
Volcans DO NOT AND CAN NOT influence global warming

Leon Brozyna

It sounds like the Gakkel Ridge is one of the least active of the oceanic rifts. Stratification sounds plausible, as the heat that is slowly released is mixed by ocean currents. (My mind wants to insist that the warming waters would rise to the surface.) Since it’s been happening for millions of years it would seem unlikely to have much effect on the surface sea ice; such an effect would have been noticed long ago, before the AGW belief system came about. It may very well be that while there is some warming going on, it’s just not enough to overcome persistent ocean currents. This sounds much different than the Tonga volcanic event. This seems to have been a much more explosive event, with heat being injected into the ocean faster than currents could disperse. Perhaps it could cause a localized temporary warming anomaly to appear.


Undersea Volcano’s are whats causing what ever ice melt that may be happening in the Artic and the Antarctic.This is one of many dirty little secret that the goverment and the media doesn’t want us to know about.Thank about it .How can ice melt at 40below ZERO????? For more on this go iceagenow.com.

Volcanism can certainly do so in the short term. The release of heat energy is intermittent not constant.

Steven Goddard

The surface expression of the volcano has just appeared, but chances are that there has been anomalous geothermal activity in the region for some time prior to the visible eruption.

Pieter F

Nice use of graphics, Steven!
A correlation of magma erupting above the crust but deep in the ocean and a warm anomaly near by makes more sense to me than rising CO2 correlating to rising temps. There are several examples of active submarine volcanoes and anomalous warmth. Back in the 80s, the British Antarctic Survey pointed out that deep volcanic activity was “lubricating” a part of the Antarctic ice shelf from the bottom, allowing it to slip more easily.
Let’s simplify this: magma at 700°C to 1300°C erupts from a crack in the crust and comes in contact with sea water at 7°C. Will the water . . .
A) . . . stay the same temperature
B) . . . become warmer.
C) . . . turn into ice.
D) none of the above.
Stratification notwithstanding, That great a difference in temperatures should influence the temperatures of adjacent thermoclines up several strata.

Lee Kington:
“The problem of course is that there are 10,000 or more submarine volcanoes, we don’t have an accurate inventory, nor are they really monitored with exception of a few.”
Actually, it was recently discovered that there are over 200,000 undersea volcanoes. 39,000 of them are over 1,000 meters [3,280 feet] high: source
alexandriu doru, these volcanoes are undoubtedly emitting astronomical amounts of various gases into the ocean and atmosphere, which neither you nor anyone else can presently quantify.
The fact that the UN/IPCC doesn’t account for 200,000+ submarine volcanoes [and is apparently even unaware of their existence] casts major doubts on the IPCC’s conclusions and competence.
What else should we expect from a politically appointed body?

Good point smokey.


As I understand it the Indian plate is pushing up above the Eurasian plate (from memory, probably wrong) — does this mean that Bangladesh will rise out of the sea and we don’t need to worry about all those millions of people inundated by rising water? Inquiring numbskulls want to know 🙂
These two links should set you on the right track:
Bangladesh should continue to gain land mass if their damn projects go ahead and sediment continues to accrue at the same rate. For years we used to see images of Bangladeshis clinging to branches as their communities were swept away by annual floods. These images haven’t been seen for some time.
The Indian Government produced a climate report entitled: ‘National Action Plan on Climate Change.’
Compared to the hysteria we in the “advanced” West receive from our dishonest, misguided and politically motivated media, the Indian report is a breath of fresh air.
Section 1.4 deals with ‘Observed Changes in Climate and Weather Events in India’ and states that, “No firm link between the documented changes described below and warming due to anthropogenic climate change has yet been established:”
The changes in climate are put down to natural variability and is presented in a balanced manner. Where they have seen rainfall increase in one region, they have seen it decrease elsewhere. Same with sea levels.


It is more likely the influence of the shallow water around the cluster of volcanoes being warmed by the sun that causes the hot spot. It takes a tremendous amount of energy to water a large volume of water, and volcanic activity, though intensely hot, simply doesn’t contain enough heat energy to warm a large volume of water by a signficant amount. The eruptions and geothermal energy may cause localized changes around each vent or each eruptive area, but there is not enough energy there to warm a large area of the ocean.

Mike Bryant

The picture that shows the topography between New Zealand and the location of the volcano is interesting. It appears that the heat at the volcano may have followed the underwater ridge and caused the upwelling of the very cold water to the east of New Zealand evident in the sst anomoly representation.

Aron (08:29:09) :
“What is that anomaly to the east of Argentina?”
I was in argentina last february and they were complaining of the drought and I heard there that sea temperatures were 4 degrees below normal at the La Plata beach. Check another source apart from NOAA’ s yellows and oranges.
There are and will be droughts in argentina:
I posted:
Adolfo Giurfa (04:38:19) :
For the known argentinian geologist Miguel Gonzales, in his studies in the “Salinas del bebedero”, a salt lake in Argentina, http://www.springerlink.com/content/m11m129238u61484/
all these weather changes coincide with solar minimums like the Maunder minimum, which produced drought in the argentinian “pampa” (plains), and which it is happening again now. So, in general, we have different weather systems: one west of the andes and the other east of the andes.


The anomaly developed before the eruption occurred:
It would be surprising if an eruption like this one (not very big) could have such an effect on ocean temps – that’s a massive volume of water to heat up to produce an anomaly like that in the first place!


“alexandriu doru (09:00:27) :
The mean geothermal flux on earth is 60 mW/m^2;
The mean solar flux on earth is 240W/m^2.
Volcans DO NOT AND CAN NOT influence global warming”
They don’t have an impact on climate (at least not until they erupt) but they certainly screw up the temperature data when they become active.

Here the abstract:
Miguel A. González1 and Nora I. Maidana2
(1) CONICET, Servicio Geológico Minero Argentino and Carl C:Zon Caldenius Foundation, C.C. 289 – Sucursal 13 (B) –, 1413 Buenos Aires, Argentina
(2) Dpto. de Biologí, Fac. de Cs, Universidad de Buenos Aires and CONICET, Exactas y Naturales – Pabellón 2, Ciudad Universitaria, 1428 Buenos Aires, Argentina
Abstract We present a climatic reconstruction of Holocene lacustrine episodes in the Salinas del Bebedero basin (Argentina), based on geological and diatom information.
Morphological, sedimentological and diatom evidence between 11600 ± 140 yr BP and 325 ± 95 yr BP, allowed us to interpret the paleoenvironments of the basin. Episodes of high energy (sandy levels) are linked to large inflow of meltwater through the Desaguadero River, related to development of glaciers on the Andes. This inflow is characterized by peaks of relative abundance of the brackish water diatom Cyclotella choctawatcheeana Prasad. The values of C. choctawatcheeana decrease in deposits of low energy (clay levels), where it co-dominates with oligohalobous Fragilaria and Epithemia spp.
To the last two peaks of large inflow of meltwater, radiocarbon dates corrected to sidereal ages, are AD 1280/1420 and AD 1443/1656. These ages agree with two cold episodes clearly recorded in dendrological studies from the Patagonian Andes and were correlated to the Little Ice Age. Thus, older Holocene episodes of large inflow of water to the basin were correlated with the Neoglacial Advances defined by Mercer (1976) for the Andes.


We sailed through the porphiry from the last eruption in 2006. It swept across the seas to the north islands of Fiji., But the eruption was nearer to tonga and there’s a new island forming.



is this particular volcano due to plate subduction or a hot spot?

Peter Hearnden

Smokey, this undersea volcoes business isn’t about AGW, it’s about maths.
Do the maths! Calculate the volume of sea water involved, the energy needed to warm it by the required amount, and any conceivable figure you can think of for the output of the volcano.
Lets us know the result……


Warmer water is less dense…. it would have to rise. And all that heat has to go somewhere… it isn’t simply disappearing.

Fred from Canuckistan . . .

“Volcans DO NOT AND CAN NOT influence global warming”
Ya, well go tell that to Mt Pinatubo !
“Large-scale volcanic activity may last only a few days, but the massive outpouring of gases and ash can influence climate patterns for years.”
No need to apologize for spreading rumors, false ones at that. We have come to expect it from Believers.

Mike Bryant

OT… Shell getting out of alternative energy at ICECAP:
The company said that many alternative technologies did not offer attractive investment opportunities. Linda Cook, Shell’s executive director of gas and power, said: “If there aren’t investment opportunities which compete with other projects we won’t put money into it. We are businessmen and women. If there were renewables [which made money] we would put money into it.”


the yellow pin of tonga and the pink arrow are not pointing at the same place!


Thanks, Adolfo

Ken Hall

Even if sub-sea currents stratify the heat from active undersea volcanoes, that is still extra heat being dispersed into the ocean. A LOT of it. That is sure to have some effect. Oh, and unless the laws of physics have fundementally changed, I believe I am right in saying that heat rises? So I cannot understand how the AGW proponents believe that, somehow, ocean currents taking a tiny increase in average air temps can drag that heat downwards, many hundreds of feet, and it still be warm when the water gets to the cold sea bed. Thus hiding “global warming” and putting it into a “pipeline” to release later. Even if the laws of physics have changed radically meaning that heat now sinks and cold rises, surely, for every litre of warm sea-water dragged down to the sea-bed, another litre of cold is presumably rising elsewhere and warming?
I will believe that thousands of active undersea volcanoes have NO effect on climate, when I see Dr Hansen walk barefoot across a sea of flowing lava without it burning his feet!

Alan Millar

Undersea volcanoes cannot really be responsible for any long term trend in global temperatures unless there is good evidence that that type of vulcanism in general is increasing or decreasing in line with observed data. Undersea volcanos will have been erupting throughout geolgical time and can only be factored in if we can confirm trends. Is there any good data on any such trends out there?
Certainly undersea eruptions can have a significant local effect but hard to see how this effects the globe.

Peter Hearnden,
You may be deliberately misunderstanding. If not, I’ll explain it for you:
Neither you, nor the UN/IPCC, nor anyone else, knows much about what is going on beneath the world’s oceans. In just the last few years the number of volcanoes discovered has gone from around ten thousand to over two hundred thousand. Despite that heat source, what little we do know indicates that the world’s oceans are cooling, not warming.
Some 70% of the Earth is covered by water, yet we know very little about the dynamics of the ocean floor. And we don’t know nearly enough about the interaction between the world’s oceans and the atmosphere.
Favoring $Trillion policy decisions based on inadequate knowledge of what occurs on the vast ocean floor — along with incomplete and often erroneous knowledge of the remaining terrestrial portion of the planet — is a flagrant waste of money.
Spending trillions of dollars without having a better knowledge of the ocean/atmosphere interface, or even good a knowledge of the source and sink of the vast majority of naturally occurring CO2, is a fool’s errand at best — if not outright dishonest.


okay, the distance between even the small yellow area one grid-block west of the arrow (est. 26S, 163W) and not the large anomaly that the arrow points towards, is nearly 900 miles from the island of tonga!
also, this from the article raises some questions “Large amounts of pumice thrown up by the erupting volcano would likely clog beaches on the southern coast of nearby Fiji islands within a short time, Mafi said.”
Fiji is NW of Tonga, so that must be some indication of the oceanic currents. that’s only 180 degrees off of the direction of the anomaly.
details, details.

Tim Clark

Lee Kington (08:34:15) :
Logic tells me that the depth of a volcano would alter its impact. Some say they have no impact. I can see that as true for a volcano at great depth. Certainly one in the Marianas Trench over 30,000 feet deep would have minimal to no effect. However, at shallower depths they must.

Defining effect as “emission, transmission, or discharge of energy” then the depth of the volcano does not alter the “effect”. Heat is transferred and water is always heated by underwater volcanos, regardless of depth. Now the “impact” of heating water at various depths is more difficult to ascertain because the affect may not be immediately detectable.


Speaking of new island formation… the formation of land above sea level would contribute to global warming since it becomes a new surface to absorb heat from the sun. When an ice age is on the way, the oceans retreive and expose more land that should absorb also more solar energy and warm up the atmosphere again. But this would lean to a cancellation of cooling if NOAA was right in thinking that the irradiance of the sun is constant and has no bearing on global warming.
So considering the exposure of new land as the planet cools and the fact that it still cools and go into an ice-age shows clearly that the sun is responsible for climate change.


re Peter Herndon 10:17:33,
The ‘maths’:
To warm an area 500km by 500km by 1 meter (warm water spreads out over the surface) a total of 2.5 deg. C requires 625 x 10*15 calories = 625 megatons of TNT. (Please recheck my ‘maths’).
My quick search didn’t find an energy equivalent for a typical volcano, but the Krakatoa explosion was rated at 200 megatons.
These numbers are certainly in the same ballpark. Maybe someone here can say whether the energy from an explosive volcano is more or less than a long-lasting lava flow volcano.


Fox News just reported a 7.9 earthquake in Tonga, with a tsunami warning. Could this be a Krakatoa type event?

Jeff L

Not sure exactly where you were going with this post , but here is some basic, simplistic math.
-Background water temp of 50 deg F (average of 30 at sea floor, 70 at surface)
– Maximum temp of 256 F that could be attained (prorated from sea level to 3500 psi = 8000 ft of water @ std gradient of 0.434 psi/ft)
see http://www.engineeringtoolbox.com/boiling-point-water-d_926.html
– Maximum delta T = 256 -50 = 206 deg F (this is a maximum, actual will be lower
– Effected area – 2 sq mi (this would be optomistic based on the photo)
– Volume effected = 8000ft*2sq mi = 3.03 cubic miles of water
If the maximum heat were spread out out 10,000 sq miles (100 by 10 miles) with the same ocean depth (8000 ft) (15,151 cubic miles) – which, based on the sat ocean temp anomaly is certainly underestimating the anomaly area, what would be the expected delta T ?
=(3.03/15151)*206 = 0.04 deg F
Observed anomaly = 2.7 deg C (4.86 deg F) – Observed is 121.5 times bigger than the calculations! And this was with optomistic assumptions. The realized anomaly would almost certainly be less.
Obviously a lot of assumptions here, but this no where even close to in the ballpark – There simiply is not nearly enough heat to make a difference. Same calculations would apply elsewhere – the fundamental problem being you can’t heat water that much before in changes to vapor – even with the high pressures of the ocean depths. Vapor escapes to the atmosphere, releasing heat to the atmosphere, not the water column
My point – Volcanic heating of ocean water & modification of climate appears to be a very very minor effect – right up there with CO2 ;0

Steven Goddard

Tsunami Warning Issued After 7.9 Magnitude Quake Hits South Pacific
Developing: A tsunami warning has been issued after a 7.9 magnitude earthquake struck in the South Pacific Thursday, 130 miles from Tonga and 300 miles from Fiji, the U.S. Geological Survey reported.