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Plate Tectonics and Earth's Climate...


Ed Stone
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Posted
  • Location: Beccles, Suffolk.
  • Weather Preferences: Thunder, snow, heat, sunshine...
  • Location: Beccles, Suffolk.

    As this topic has been being discussed in the Sceptics' thread, I though that we might try giving it a topic of its own...

     

    So here goes...over to you JP.Posted Image 

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    Posted
  • Location: Mytholmroyd, West Yorks.......
  • Weather Preferences: Hot & Sunny, Cold & Snowy
  • Location: Mytholmroyd, West Yorks.......

    I think there have been geological periods were rapid changes in plate tectonics have lead to atmospheric forcings but we do not see any such impacts from the constructive and destructive plate margins at this time in the earths history.

     

    We have spent the past ice ages under similar conditions and not seen any great departure from this 'norm' over those tens of thousands of years.

     

    It is a similar story with our Sun. We have seen no great departures from it's 'average functioning' over a similar time period.

     

    Why a sudden interest now in such 'average' situation?

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    Posted
  • Location: Beccles, Suffolk.
  • Weather Preferences: Thunder, snow, heat, sunshine...
  • Location: Beccles, Suffolk.

    I think there have been geological periods were rapid changes in plate tectonics have lead to atmospheric forcings but we do not see any such impacts from the constructive and destructive plate margins at this time in the earths history.

     

    We have spent the past ice ages under similar conditions and not seen any great departure from this 'norm' over those tens of thousands of years.

     

    It is a similar story with our Sun. We have seen no great departures from it's 'average functioning' over a similar time period.

     

    Why a sudden interest now in such 'average' situation?

    So that it can be discussed without our falling foul of sceptics' thread...

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    Posted
  • Location: Near Newton Abbot or east Dartmoor, Devon
  • Location: Near Newton Abbot or east Dartmoor, Devon

    As this topic has been being discussed in the Sceptics' thread, I though that we might try giving it a topic of its own...

     

    So here goes...over to you JP.Posted Image 

    Tectonic plates move at most, what, a few cm a year? This is so tiny in relation to earth's size that while they are real changes (and probably big over geological time scales) any changes due to tectonic movements simply can't have effect on a human lifetime(s) scales wrt climate?

    Edited by Devonian
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    Posted
  • Location: Ireland, probably South Tipperary
  • Weather Preferences: Cold, Snow, Windstorms and Thunderstorms
  • Location: Ireland, probably South Tipperary

    Tectonic plate move at most, what, a few cm a year? This is so tiny in relation to earth's size that while they are real changes (and probably big over geological time scales) any changes due to tectonic movements simply can't have effect on a human lifetime(s) scales wrt climate.

     

    Unless something like the Messinian Salinity Crisis was to occur again.

     

    The Messinian Salinity Crisis (MSC), also referred to as the Messinian Event, and in its latest stage as the Lago Mare event, was a geological event during which the Mediterranean Sea went into a cycle of partly or nearly complete desiccation throughout the latter part of the Messinian age of the Miocene epoch, from 5.96 to 5.33 Ma (million years ago). It ended with the so-called Zanclean flood, when the Atlantic reclaimed the basin...

     

    ...  As winds blew across the "Mediterranean Sink", they would heat or cool adiabatically with altitude. In the empty Mediterranean Basin the summertime temperatures would probably have been extremely high even during the coldest phase of any glacial era. Using the dry adiabatic lapse rate of around 10°C (18°F) per kilometer, a theoretical temperature of an area 4 kilometres (2.5 mi) below sea level would be about 40°C (72°F) warmer than the temperature at sea level. Thus one could predict[original research?] theoretical temperature maxima of around 80°C (176 °F) at the lowest depths of the dry abyssal plain permitting little known life to survive there. One can also calculate that 2 to 3 miles (3.2 - 4.8 km) below sea level would have resulted in 1.45 to 1.71 atm (1,102 to 1,300 mmHg) of air pressure at the bottom. Although it was probably quite dry in the Basin, there is no direct way to measure how much drier it would have been compared to its surroundings. Areas with less severe depths would probably have been very dry.

     

    Death Valley's 57C, pah!

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    Posted
  • Location: Near Newton Abbot or east Dartmoor, Devon
  • Location: Near Newton Abbot or east Dartmoor, Devon

    Unless something like the Messinian Salinity Crisis was to occur again.

     

    The Messinian Salinity Crisis (MSC), also referred to as the Messinian Event, and in its latest stage as the Lago Mare event, was a geological event during which the Mediterranean Sea went into a cycle of partly or nearly complete desiccation throughout the latter part of the Messinian age of the Miocene epoch, from 5.96 to 5.33 Ma (million years ago). It ended with the so-called Zanclean flood, when the Atlantic reclaimed the basin...

     

    ...  As winds blew across the "Mediterranean Sink", they would heat or cool adiabatically with altitude. In the empty Mediterranean Basin the summertime temperatures would probably have been extremely high even during the coldest phase of any glacial era. Using the dry adiabatic lapse rate of around 10°C (18°F) per kilometer, a theoretical temperature of an area 4 kilometres (2.5 mi) below sea level would be about 40°C (72°F) warmer than the temperature at sea level. Thus one could predict[original research?] theoretical temperature maxima of around 80°C (176 °F) at the lowest depths of the dry abyssal plain permitting little known life to survive there. One can also calculate that 2 to 3 miles (3.2 - 4.8 km) below sea level would have resulted in 1.45 to 1.71 atm (1,102 to 1,300 mmHg) of air pressure at the bottom. Although it was probably quite dry in the Basin, there is no direct way to measure how much drier it would have been compared to its surroundings. Areas with less severe depths would probably have been very dry.

     

    Death Valley's 57C, pah!

     

    Indeed, but not strictly due to the movement of plates rather the Med being land locked at that time and having varying amounts of fresh water supply as climate changed giving varying amounts of dessication? As the article says "Even now the Mediterranean is saltier than the North Atlantic because of its near isolation by the Strait of Gibraltar and its high rate of evaporation. If the Strait of Gibraltar closes again, which is likely to happen in the near geological future (though extremely distantly on a human time scale)..."

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    Posted
  • Location: North Yorkshire
  • Weather Preferences: Extended Mediterranean heatwaves
  • Location: North Yorkshire

    Well, lots of things come to mind, but first I thought it would be useful to deconstruct the 'sceptic' line. As there are several lines of attack, so there are variations and additions, but this as I understand it is the main line of reasoning:

     

    1. Volcanoes are hot. Very hot.

    2. There are volcanoes under the sea.

    3. Heat transfers from hot to cold.

    4. Therefore volcanoes are heating the sea.

     

    Add to this the 'science is worthless' meme:

     

    5. Volcanoes are heating the sea.

    6. We (including scientists) don't know how many volcanoes there are under the sea.

    7. Therefore nobody knows how much the sea is being heated by volcanoes.

     

    Incorporate this into AGW:

     

    8. Nobody knows how much volcanoes are heating the sea.

    9. GWers are saying the sea is getting hotter.

    10. We know that it isn't us.

    11. Therefore It must be the volcanoes.

     

    Did I miss anything?

    :)

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    Posted
  • Location: Camborne
  • Location: Camborne

    Tectonic plates move at most, what, a few cm a year? This is so tiny in relation to earth's size that while they are real changes (and probably big over geological time scales) any changes due to tectonic movements simply can't have effect on a human lifetime(s) scales wrt climate?

     

    Actually this varies quite a bit Dev.

     

    The rate at which different tectonic plates separate varies considerably. While the American and European-African plates are moving apart at rates of between 20 and 60 mm/yr (roughly the speed at which fingernails grow), the American and Pacific plates are distancing themselves at nearly ten times that speed. The type of sea floor generated at these different speeds is usually very different, in terms of the topography and the composition of the basaltic rocks generated to make the crust. In general,faster-spreading ridges are characterised by an elevated crestal region, while slower spreading systems have a well-defined axial valley or trough, marked by inward-facing fault scarps which may have more than 500 m of throw. The faults bound an axial floor, commonly 10-12 km wide, within which a range of neovolcanic and neotectonic activity takes place. Volcanoes, which are commonly distributed across the axial floor, are fed through a complex system of pipes and cracks which connects them to magma chambers. The magma has risen and ponded in shallow levels of the crust, in what are believed to be discrete supply systems following the melting of crustal rock during the uprise of heat from the upper mantle.

     

    inevitably, as the plates continue to move apart, sediments accumulate on the surface of the crust, burying the volcanic and tectonic features which characterise the ridge.

    Edited by knocker
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    Posted
  • Location: Beccles, Suffolk.
  • Weather Preferences: Thunder, snow, heat, sunshine...
  • Location: Beccles, Suffolk.

    Well, lots of things come to mind, but first I thought it would be useful to deconstruct the 'sceptic' line. As there are several lines of attack, so there are variations and additions, but this as I understand it is the main line of reasoning:

     

    1. Volcanoes are hot. Very hot.

    2. There are volcanoes under the sea.

    3. Heat transfers from hot to cold.

    4. Therefore volcanoes are heating the sea.

     

    Add to this the 'science is worthless' meme:

     

    5. Volcanoes are heating the sea.

    6. We (including scientists) don't know how many volcanoes there are under the sea.

    7. Therefore nobody knows how much the sea is being heated by volcanoes.

     

    Incorporate this into AGW:

     

    8. Nobody knows how much volcanoes are heating the sea.

    9. GWers are saying the sea is getting hotter.

    10. We know that it isn't us.

    11. Therefore It must be the volcanoes.

     

    Did I miss anything?

    Posted Image

    That would appear to sum it all, Fergus...

     

    Edit: And I most certainly do not subscribe to it!Posted Image 

    Edited by A Boy Named Sue
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    Posted
  • Location: Near Newton Abbot or east Dartmoor, Devon
  • Location: Near Newton Abbot or east Dartmoor, Devon

     

    Tectonic plates move at most, what, a few cm a year? This is so tiny in relation to earth's size that while they are real changes (and probably big over geological time scales) any changes due to tectonic movements simply can't have effect on a human lifetime(s) scales wrt climate?

     

    Actually this varies quite a bit Dev.

     

    The rate at which different tectonic plates separate varies considerably. While the American and European-African plates are moving apart at rates of between 20 and 60 mm/yr (roughly the speed at which fingernails grow), the American and Pacific plates are distancing themselves at nearly ten times that speed. The type of sea floor generated at these different speeds is usually very different, in terms of the topography and the composition of the basaltic rocks generated to make the crust. In general,faster-spreading ridges are characterised by an elevated crestal region, while slower spreading systems have a well-defined axial valley or trough, marked by inward-facing fault scarps which may have more than 500 m of throw. The faults bound an axial floor, commonly 10-12 km wide, within which a range of neovolcanic and neotectonic activity takes place. Volcanoes, which are commonly distributed across the axial floor, are fed through a complex system of pipes and cracks which connects them to magma chambers. The magma has risen and ponded in shallow levels of the crust, in what are believed to be discrete supply systems following the melting of crustal rock during the uprise of heat from the upper mantle.

     

    inevitably, as the plates continue to move apart, sediments accumulate on the surface of the crust, burying the volcanic and tectonic features which characterise the ridge.

     

    As with Born's post nothing to disagree with there. I'm just sayin' such rates of movement are unlikely to have an effect on the climate over human timescales? Posted Image

    Well, lots of things come to mind, but first I thought it would be useful to deconstruct the 'sceptic' line. As there are several lines of attack, so there are variations and additions, but this as I understand it is the main line of reasoning:

     

    1. Volcanoes are hot. Very hot.

    2. There are volcanoes under the sea.

    3. Heat transfers from hot to cold.

    4. Therefore volcanoes are heating the sea.

     

    Add to this the 'science is worthless' meme:

     

    5. Volcanoes are heating the sea.

    6. We (including scientists) don't know how many volcanoes there are under the sea.

    7. Therefore nobody knows how much the sea is being heated by volcanoes.

     

    Incorporate this into AGW:

     

    8. Nobody knows how much volcanoes are heating the sea.

    9. GWers are saying the sea is getting hotter.

    10. We know that it isn't us.

    11. Therefore It must be the volcanoes.

     

    Did I miss anything?

    Posted Image

    That would seem to be the view of those who support the notion. Occam would turn in his grave...

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    Posted
  • Location: North Yorkshire
  • Weather Preferences: Extended Mediterranean heatwaves
  • Location: North Yorkshire

    Volcanoes do have an effect on the climate - they have a cooling effect. This is so well established by experiment, observation and simple accounting, that arguing to the contrary is possible only if you choose to ignore all of the evidence.

     

    There are many things to say about the argument above, but keeping things simple; there are three recognised 'ocean levels' - upper, middle and lower. Recent measurements show the upper ocean is warming at a measurable rate. At the same time it is getting more acid. There is a known mechanism for both these - increased heat from above (the air) and increased CO2 absorbed into the water. The relationship between the increases in atmospheric CO2, oceanic CO2, atmospheric temperature and upper sea temperature can be established through calculation and accounting.

     

    There is a relation between top and bottom water (mixing), and there is circulation of water (the THC, broadly). The measurements of these processes indicate that the transfer of heat is going from the top to the bottom, rather than the other way around. Eventually, it will come back out again.

     

    There is no evidence that the amount of volcanic activity in terms of heat generated has changed in any way which can explain the concurrent change in GST.

     

    Lots of others, but this will do for now...

    :)

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    Posted
  • Location: Evesham, Worcs, Albion
  • Location: Evesham, Worcs, Albion

    Well, lots of things come to mind, but first I thought it would be useful to deconstruct the 'sceptic' line. As there are several lines of attack, so there are variations and additions, but this as I understand it is the main line of reasoning:

     

    1. Volcanoes are hot. Very hot.

    2. There are volcanoes under the sea.

    3. Heat transfers from hot to cold.

    4. Therefore volcanoes are heating the sea.

     

    Add to this the 'science is worthless' meme:

     

    5. Volcanoes are heating the sea.

    6. We (including scientists) don't know how many volcanoes there are under the sea.

    7. Therefore nobody knows how much the sea is being heated by volcanoes.

     

    Incorporate this into AGW:

     

    8. Nobody knows how much volcanoes are heating the sea.

    9. GWers are saying the sea is getting hotter.

    10. We know that it isn't us.

    11. Therefore It must be the volcanoes.

     

    Did I miss anything?

    Posted Image

     

     

    A point I have made before with regards the "oceans warming due to more underwater volcanoes" argument is: how do we know that current underwater vulcanicity isn't unusually low?

    Just because we keep finding new underwater volcanoes doesn't mean that 1,000, 10,000 or 100,000 years ago there was not much greater underwater activity.

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    Posted
  • Location: Mytholmroyd, West Yorks.......
  • Weather Preferences: Hot & Sunny, Cold & Snowy
  • Location: Mytholmroyd, West Yorks.......

    I think the major action occurs with the opening up of ocean basins? were we to wait a few odd lifetimes we'd see the African Rift valley opening into a new ocean and that would involve a little uptick in volcanic activity in the region as the crust collapsed into the earth and molten rock filled the fissure.... or something along those lines.

     

    I think what these guys are looking for is an event like that which filled the Deccan traps with km's of lava back in the day???

     

    I somehow think we'd notice a change on that scale....don't you?

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    Posted
  • Location: North Yorkshire
  • Weather Preferences: Extended Mediterranean heatwaves
  • Location: North Yorkshire

    Good point, Andy. 

     

    It's the usual problem, though (see for example the skeptic thread recently); for every piece of evidence provided by careful methodology and assiduous examination, there is a website which presents its own version of 'evidence', very frequently sourced second-hand from another site, which got it from another site, which got it from (eventually) an organised, funded misinformationist source.

     

    It doesn't matter whether this 'evidence' is scientifically accurate, just so long as it looks scientific and is plausible, and supports a pre-existing opinion help by a reader - it will be believed, and assumed to have an equivalent value, at least, as the sum of all evidence which contradicts it.

     

    This is not necessarily the 'fault' of the reader though. There are few enough of us who are genuinely scientifically literate, and even fewer who have the skills to analyse, for example, the formulae used in presentations. If we are asked to choose between two things on face value, we tend to choose the one which suits our existing disposition.

     

    So the challenge for someone who wants to try to offer persuasive argument without alienating or being seen as hostile by a 'skeptical' other person (and this holds true for much of science, such as GM), is how to open the door to engagement and hold it open? How to create the conditions for a real dialogue which allows the other to both own their existing opinions and genuinely consider alternative opinions? It's a big ask...

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    Posted
  • Location: Camborne
  • Location: Camborne

    A point I have made before with regards the "oceans warming due to more underwater volcanoes" argument is: how do we know that current underwater vulcanicity isn't unusually low?Just because we keep finding new underwater volcanoes doesn't mean that 1,000, 10,000 or 100,000 years ago there was not much greater underwater activity.

     

    Good point and the following suggests to me that warming would be localized unless the activity was massive.

     

    Underwater Antarctic volcanoes discovered in the Southern Ocean

     

    Scientists from British Antarctic Survey (BAS) have discovered previously unknown volcanoes in the ocean waters around the remote South Sandwich Islands. Using ship-borne sea-floor mapping technology during research cruises onboard the RRS James Clark Ross, the scientists found 12 volcanoes beneath the sea surface – some up to 3km high. They found 5km diameter craters left by collapsing volcanoes and 7 active volcanoes visible above the sea as a chain of islands.

     

    The research is important also for understanding what happens when volcanoes erupt or collapse underwater and their potential for creating serious hazards such as tsunamis. Also this sub-sea landscape, with its waters warmed by volcanic activity creates a rich habitat for many species of wildlife and adds valuable new insight about life on earth.

     

    Speaking at the International Symposium on Antarctic Earth Sciences in Edinburgh Dr Phil Leat from British Antarctic Survey said,

    "There is so much that we don't understand about volcanic activity beneath the sea – it's likely that volcanoes are erupting or collapsing all the time. The technologies that scientists can now use from ships not only give us an opportunity to piece together the story of the evolution of our earth, but they also help shed new light on the development of natural events that pose hazards for people living in more populated regions on the planet."

     

    http://www.eurekalert.org/pub_releases/2011-07/bas-uav071111.php

    Edited by knocker
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    Posted
  • Location: Evesham, Worcs, Albion
  • Location: Evesham, Worcs, Albion

    I think the major action occurs with the opening up of ocean basins? were we to wait a few odd lifetimes we'd see the African Rift valley opening into a new ocean and that would involve a little uptick in volcanic activity in the region as the crust collapsed into the earth and molten rock filled the fissure.... or something along those lines.

     

    I think what these guys are looking for is an event like that which filled the Deccan traps with km's of lava back in the day???

     

    I somehow think we'd notice a change on that scale....don't you?

     

     

    Aye, a flood basalt eruption - now that, I concur, would certainly affect climate.  But yes, I think we'd notice if that happened.And a shorter term change due to a supervolcano eruption would also, I think, also be noticed. Though I've not heard any reports from Yellowstone today .... :oOn that subject, Greenland ice cores suggest that the very coldest period of the last ice age occurred around the same time as te Toba eruption ~72ka, and was followed by a very rapid, massive, warming. I think evidence of an initial 'nuclear winter' followed by the effects of CO2 induced global warming (CO2 staying in the atmopshere longer than the initial dust and sulphur etc).  

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    Posted
  • Location: west croydon (near lombard)
  • Location: west croydon (near lombard)

    find some links to read here

     

    http://www.geomar.de/index.php?id=4&no_cache=1&tx_ttnews[tt_news]=1047&tx_ttnews[backPid]=185&L=1

     

    http://www.thelocal.no/20130802/Volcanic-range-discovered-in-Norwegian-waters

     

    http://www.nature.com/news/underwater-volcano-is-earth-s-biggest-1.13680

    Geophysicists have discovered what they say is the largest single volcano on Earth, a 650-kilometre-wide beast the size of the British Isles lurking beneath the waters of the northwest Pacific Ocean.

    Because ship time is at a premium, the study is one of the first to peer at the internal geometry of these massive underwater mountains. It is possible that other megavolcanoes are waiting to be discovered. “There may be bigger ones out there,†says Sager.

     

    SAN FRANCISCO — Scientists have discovered one of the world's weirdest volcanoes on the seafloor near the tip of Baja, Mexico.

     

    http://news.discovery.com/earth/videos/earth-underwater-volcano-caught-on-video.htm

     

     

    http://www.nzherald.co.nz/nz/news/article.cfm?c_id=1&objectid=10709388

    In a surprise finding, undersea hot lava is baking ocean sediments and releasing greenhouse gases.

     

    http://geology.gsapubs.org/content/early/2012/11/30/G33419.1.abstract?sid=5fa39e0d-d09f-492a-912a-121b6e20b997

    In particular, increased volcanism lags behind the highest rate of increasing eustatic sea level (decreasing global ice volume) by 4.0 ± 3.6 k.y. and correlates with numerical predictions of stress changes at volcanically active sites. These results support the presence of a causal link between variations in ice age climate, continental stress field, and volcanism

     

    http://geology.gsapubs.org/content/current

    tons of links there

     

     

    http://earthsciencesus.blogspot.co.uk/2008/01/volcanic-heating-is-melting-ice-caps.html

    Geothermal heat is melting the ice caps.

    A study published today, January 20, 2008, reveals the probable main source of the receding ice caps and climate change. The study by the British Antarctic Survey (BAS) showed the proof of a massive volcanic eruption that melted a large portion of ice shelf some 2000 years ago. The study speculates that the subterranean heating is still on going in this present day and calls for more extensive studies.

    The location of the volcano is close to the Pine Island Glacier, the same area experiencing the greatest ice sheet LOSS today

     

    http://en.wikipedia.org/wiki/Category:Underwater_ridges_of_the_Arctic_Ocean

     

    http://www.bbc.co.uk/science/earth/natural_disasters/volcano

    Erupting volcanoes can pose many hazards, not only in the immediate vicinity of the eruption. Volcanic ash can be a threat to aircraft, in particular those with jet engines where ash particles can be melted by the high operating temperature; the melted particles then adhere to the turbine blades and alter their shape, disrupting the operation of the turbine. Large eruptions can affect temperature as ash and droplets of sulfuric acid obscure the sun and cool the Earth's lower atmosphere or troposphere; however, they also absorb heat radiated up from the Earth, thereby WARMING the stratosphere. Historically, so-called volcanic winters have caused catastrophic famines.

     

    http://onlinelibrary.wiley.com/doi/10.1002/grl.50993/abstract

     

    http://geology.gsapubs.org/content/41/3/381.full

     

     

    http://onlinelibrary.wiley.com/doi/10.1002/2013GL057282/abstract#grl51037-note-0001

     

    http://www.astrobio.net/exclusive/201/

    "Unfortunately, instruments are not yet developed to characterize microbial populations," says Kelley, although culturing samples back in the lab has shown heat-loving microorganisms adapted to thrive in the thermophilic (50-70 C) and mesophilic (25 C) temperature ranges. "The long term goal is to develop seafloor observatory sites that will allow long term investigation of how volcanoes support life on the seafloor, and how submarine earthquakes affect the output of gases from the seafloor and microbial life.

     

    http://www.rmg.co.uk/subject/maritime/marine-environment/deep-sea-exploration-and-discovery/submarine-volcanoes

    The seawater that percolates down deep within submarine volcanoes gets heated to temperatures of up to 400°C, before it spurts out onto the sea floor. While the seawater is being heated it reacts with the molten rocks and dissolves their metals and other minerals such as sulphur. Hydrothermal vent fluids are therefore rich in chemicals. As this fluid rises it is cooled by the surrounding seawater and the minerals it contains precipitate. This cooling process results in thick rising plumes of blue-black, sulphide-mineral smoke – hence their common name of 'black smokers’. Typically these smoke plumes rise from 330 to 1000 feet (100–300 m) above the sea floor before they become too diluted to ascend further.

    Although these features are now know to be central to ocean processes, they were only discovered in 1979. Since then more than 200 seafloor vent sites have been located. Scientists have now discovered that these plumes are of fundamental importance to the composition of the oceans

     

    http://rsrc.kaust.edu.sa/Pages/volcanic-signals-in-oceans.aspx

    ​Sulfate aerosols resulting from strong volcanic explosions last for 2-3 years in the lower stratosphere. Therefore it was traditionally believed that volcanic impacts produce mainly short-term, transient climate perturbations. However, the ocean integrates volcanic radiative cooling and responds over a wide range of time scales. The associated processes, especially ocean heat uptake, play a key role in ongoing climate change. However, they are not well constrained by observations, and attempts to simulate them in current climate models used for climate predictions yield a range of uncertainty. Volcanic impacts on the ocean provide an independent means of assessing these processes. This study focuses on quantification of the seasonal to multidecadal time scale response of the ocean to explosive volcanism. It employs the coupled climate model CM2.1, developed recently at the National Oceanic and Atmospheric Administration's Geophysical Fluid Dynamics Laboratory, to simulate the response to the 1991 Pinatubo and the 1815 Tambora eruptions, which were the largest in the 20th and 19th centuries, respectively. The simulated climate perturbations compare well with available observations for the Pinatubo period. The stronger Tambora forcing produces responses with higher signal-to-noise ratio. Volcanic cooling tends to strengthen the Atlantic meridional overturning circulation. Sea ice extent appears to be sensitive to volcanic forcing, especially during the warm season. Because of the extremely long relaxation time of ocean subsurface temperature and sea level, the perturbations caused by the Tambora eruption could have lasted well into the 20th century.
     

    We conservatively estimate that 3.26×108 mol of methane have been discharged from the seep site since the earthquake. We therefore suggest that hydrocarbon seepage triggered by earthquakes needs to be considered in local and global carbon budgets at active continental margins.

     

    how much do we know about under the sea

     

     

    http://en.wikipedia.org/wiki/Submarine_volcano

    Scientists still have much to learn about the location and activity of underwater volcanoes. The Kolumbo underwater volcano in the Aegean Sea was discovered in 1650 when it burst from the sea and erupted, killing 70 people on the nearby island of Santorini. More recently, NOAA's Office of Ocean Exploration has funded exploration of submarine volcanoes, with the Ring of Fire missions to the Mariana Arc in the Pacific Ocean being particularly noteworthy. Using Remote Operated Vehicles, scientists studied underwater eruptions, ponds of molten sulfur, black smoker chimneys and even marine life adapted to this deep, hot environment.

     

     

     

     

     

    http://volcanology.geol.ucsb.edu/erupt.htm

    volcanoes emit co2 when not in eruptive state

     

    anyway this lot is for you to read

     

    most people have made there own minds up anyway so not sure why this thread was started

     

    a couple of points

     

    saying volcanoes cannot heat the planet is the same as saying co2 does not warm the planet as well

     

    also circualtion transport heat from the bottom of the oceans and not just heat from the surface

     

    also deep eruption do not always get noticed and you also do not always get earthquakes to foretell an eruption

     

    until the deep oceans have been properly mapped and discovered i will keep an open mind

     

    anyway make your own minds up on this

     

     

     

     

     

     

     

     

     

     

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    Posted
  • Location: PO1 5RF
  • Location: PO1 5RF

    For on moment, imagine if the earth had 2 suns.

     

    One, the one we know so well, which is the source of all of our incident energy, more or less, 93 million miles away, radiating with a surface temperature of 5 to 6 thousand deg C.

     

    The other one, with apparent diameter from earth, and apparent temperature the same, but where the moon is, a quarter of a million miles away, orbiting just like the moon does.

     

    How would that change the conditions on earth? Twice as much incoming energy, but with a highly variable frequency of irradiation.

     

    Now instead of where the moon is, move that glowing sphere of energy, radiating with the black body temperature of an estimated 5 to 6 thousand deg C to about 2,000 miles away from every point on the earth's surface.

     

    The only way to do that is to move it inside the earth.

     

    Hang on though, it's there already!

     

    If  you had created a vertical shaft 2,000 miles deep, the surface at the bottom would glow like the sun.

     

    It is estimated at that temperature because the pressure, density and physical characteristics suggest a solid core of iron and nickel and a fluid core surrounding it of iron and nickel with some oxide and silicate components helping to keep it fluid like a solderer's flux.

     

    Its been there for 4.5 billion years, cooling at a rate of perhaps a degree or less per century, but also has an energy source of an unknown quantity of fissile nuclear fuel keeping it hot, according to all the estimates that have been made, meaning that the data we have about it is actually quite sparse.

     

    That this is a negligible source of heating at the surface (or any number of points near the surface) is just as much of an educated guess.

     

    It could be described as a large known unknown.

     

    The IPCC does not figure it is worthy of a mention in the current climate analysis.

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    Posted
  • Location: Beccles, Suffolk.
  • Weather Preferences: Thunder, snow, heat, sunshine...
  • Location: Beccles, Suffolk.

    My question is: Ignoring, for the moment, geologic deep-time, how does the discovery of 'new' volcanoes (however large they happen to be) account for 20th Century global warming? After all, mid-oceanic spreading-ridges and subduction zones have been exuding C02 since the day they formed...Many Ma before anyone happened to discover them.

     

    So, why have a thread dedicated to this subject? So that those who support this theory can explain it to those of us who remain unconvinced...

    Edited by A Boy Named Sue
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    Posted
  • Location: North Yorkshire
  • Weather Preferences: Extended Mediterranean heatwaves
  • Location: North Yorkshire

    Hi John,

     

    anyway this lot is for you to read

     

    most people have made there own minds up anyway so not sure why this thread was started

    I think it was started because someone thought it was worth discussing, with the difference that the presumption implicit in the discussion on the other thread was removed.

    a couple of points

     

    saying volcanoes cannot heat the planet is the same as saying co2 does not warm the planet as well

    Sorry, we are talking at cross purposes here - what do you mean when you say 'volcanoes heat the planet'?

    The impact of volcanism on climate has been studies for quite a long time and is taken very seriously. It is not ignored in the science.

    Making the statements you quote - are they of equal status? Surely, that is what we are trying to get to?

    also circualtion transport heat from the bottom of the oceans and not just heat from the surface

    Please note I mentioned this in a previous post. Are you suggesting that this is not factored in to the analysis done by scientists?

    also deep eruption do not always get noticed and you also do not always get earthquakes to foretell an eruption

    I agree.

    until the deep oceans have been properly mapped and discovered i will keep an open mind

    I am delighted that you are keeping an open mind, seriously. Can you point me to an explanation of the relationship between ocean temperatures and subsea volcanoes?

    anyway make your own minds up on this

    I think we are all trying to do this, all the time. Please don't stop pushing the point.

     

    A small side point; your post references are a bit long, which mean there is rather a lot to take in at once. I'd find it easier to focus on one or at most two pieces of material at a time. (won't speak for other people). For example, I'd appreciate it if you can find a paper on the earth-ocean heat exchange. Please don't post a part of a textbook, though - I think you can presume that your readers already understand how volcanoes work. 

     

    I look forward to continuing this discussion in a positive and open-minded way.

    :)

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    Posted
  • Location: North Yorkshire
  • Weather Preferences: Extended Mediterranean heatwaves
  • Location: North Yorkshire

    Hi Timini,

     

    Getting to the point of your post:

     

    That this is a negligible source of heating at the surface (or any number of points near the surface) is just as much of an educated guess.

    I had imagined that the Earth's energy budget incorporates 'background' heat, such as you describe. I am fairly certain that there is quite a lot of observation and analysis  which accounts for this contribution. Therefore I can't agree that such a conclusion would be an 'educated guess'. Scientists are quite fussy about this kind of ambiguity on the whole. Can you post anything which shows the estimated heat at the global surface from Earth's own 'internal sun'? Hopefully, this will also show a level of uncertainty about the calculation.

    It could be described as a large known unknown.

    It could be described this way if it is true. Is it unknown?

    The IPCC does not figure it is worthy of a mention in the current climate analysis.

    Do you think that it is possible that there is a legitimate reason for this? 

     

    Cheers. :)

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    Posted
  • Location: Ireland, probably South Tipperary
  • Weather Preferences: Cold, Snow, Windstorms and Thunderstorms
  • Location: Ireland, probably South Tipperary
     

     

    find some links to read here

     

    ......................................................................

     

    anyway this lot is for you to read

     

    most people have made there own minds up anyway so not sure why this thread was started

     

    a couple of points

     

    saying volcanoes cannot heat the planet is the same as saying co2 does not warm the planet as well

     

    also circualtion transport heat from the bottom of the oceans and not just heat from the surface

     

    also deep eruption do not always get noticed and you also do not always get earthquakes to foretell an eruption

     

    until the deep oceans have been properly mapped and discovered i will keep an open mind

     

    anyway make your own minds up on this

     

     

     

     

    Hi John, I've read through your links, perhaps you can explain the relevance of some. I'm struggling to see links to climate and they seem more against your view than in favour of it.

     

    Link 1: Climate change causes changes in volcanism by quickly changing stress level as weight is transferred from continental to oceanic plates as ice sheets and glaciers melt.

     

    Link 2: New chain of volcanoes discovered between Jan Mayan and Lokis castle. No connection to climate change.

     

    Link 3: Very large undersea volcano discovered. No connection to climate change.

     

    Link 4: A volcano at an ocean ridge produces rhyolitic lava, more typical of continentally sourced magama, such as at convergent plate boundaries. No connection to climate change.

     

    Link 5: Video showing the formation of pillow lavas. No connection to climate change.

     

    Link 6: Nothing to do with your description. Just a very vague piece on some underwater volcanoes that have been explored and their mineral value. No connection to climate change. 

     

    Link 7: A study agreeing with that in link 1, climate change causes changes in volcanism, by redistributing weight from the continents to the oceans and changing the stress levels.

     

    Link 8: Lots of links to generic geology papers.

     

    Link 9: A poor review, misrepresenting a BAS discovery of a volcano and massive eruption around 240BC in the West Antarctic Ice Sheet. The actual BAS paper is here and their own press release on it here

     

    Link 10: Wiki link to oceanic ridges in the Arctic. No connection to climate change

     

    Link 11:  BBC piece on the effects of volcanoes, including weather impacts. No connection to climate change

     

    Link 12: Research abstract on regional tectonics in California. No connection to climate change

     

    Link 13: Article on underwater island volcanism. No connection to climate change

     

    Link 14: Article examining the link between sub polar north Atlantic sea ice and tropical volcanism. They find that more volcanism = more sea ice

     

    Link 15: Arctic on volcanic vents in the mid Atlantic. No connection to climate change.

     

    Link 16: Introductory piece on underwater volcanism. No connection to climate change.

     

    Link 17: A particularly interesting research paper on climate simulations of the Tambora and Pinatubo eruptions, mainly on their effect on sea ice and the AMOC. Eruptions increase mixing, but reduce overall oceanic heat content. Effects may last over a century according to the simulations. The full paper (PDF) is here

     

    Link 18:  Paper on  the relevance of major subduction zone earthquakes and their hydrocarbon releases to the Earths carbon budget.

     

    Link 19: Small wiki piece on submarine volcanoes. No connection to climate change

     

    Link 20: A piece on different types of volcanic eruptions. No connection to climate change

     

     

    Most of the links have no relevance to climate change, with just a mix of different geology, tectonics and volcanology, introductions, research and reviews. Can you point me to the evidence that says oceanic volcanism is causing a significant portion of current climate change?

     

    Volcanoes cannot heat the planet, in the sense that the are the result of the planets heat, but they can certainly influence the surface temperature. Their impacts on the ocean and atmosphere are well studied, it's certainly not something that's ignored. But it seems that they're more likely to cause cooling than warming, based on the links you've posted.

     

    If you think it's mainly undersea volcanoes that caused much of the ocean and atmospheric warming, then why aren't the ocean depths heating faster than the surface? Is there any evidence of increased undersea volcanism?

     

    I agree with keeping an open mind on the oceans depths. We never know what may be found. But it does seem highly, and increasingly, unlikely that we'll find something to revolutionise our thinking on current climate change. I'm open to you changing my mind though!

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    Posted
  • Location: Camborne
  • Location: Camborne

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