DescentBB

Now you don't. Reports from the fear mongering press is telling a tale of a possible ice free arctic ocean this summer:

http://www.independent.co.uk/environmen ... 55406.html

But wait. Something is missing. Something not mentioned to be a fair and balanced report. Thankfully you have me to elucidate you. Seems that there has been massive underwater volcanoes erupting under the ocean:

\"Both sonar and visual images showed an ocean valley filled with flat-topped volcanos up to two kilometres (1.2 miles) wide and several hundred metres high.\"

http://news.yahoo.com/s/afp/20080625/sc ... ansvolcano

So the question is, would the vulcanism inject enough heat to help melt the ice sheet abouve it?

The eruptions -- as big as the one that buried Pompei -- took place in 1999 along the Gakkel Ridge, an underwater mountain chain snaking 1,800 kilometres (1,100 miles) from the northern tip of Greenland to Siberia.

9 years ago. You think it's still hot enough to melt 10,000 year old ice? I don't.

Not likely. At a 13,000 foot depth, there's too much water in between the ice and the heat generated by any volcanic activity at the bottom. Water is a very good insulator, so the volcanoic activity would have to rise much nearer to the surface to have any effect. Another factor is that any currents would tend move the heated water away from the affected area as well.

How do deep-water currents behave? We know that hot water, like hot air, will rise (lower density). Eventually, some percentage of the heat released underwater is making it to the surface. The questions at hand:

1) how much of the heat reaches the surface?
2) what area is it spread over (via currents, etc.)?
3) how long does it take?

I don't know what deep water currents are in the area, but there are other factors, like salinity and pressure, that can keep a warmer water layer from rising upward. Somebody would have to study the dynamics of the ocean in the area to see what is going on. The Black Sea is a good example of saline layering. There is a very dense layer of saline water that lies below a layer of fresher water that is so stable that storms don't really disrupt it or cause much mixing. Nothing even grows in it and even wood doesn't rot. It's stable and lifeless.

However, 13,000 feet (almost three miles) is a lot of depth and volume of water for heat to penetrate, and it's not stationary at the bottom or at the surface. Think of how much energy input it requires to heat water on the stove. There are also very active and hot deep volcanic vents that superheat the water in the Atlantic and Pacific Oceans, but we don't see any of that heat at the surface from those areas.

Edit: I just remembered about some old film footage years ago of divers taking pictures of pillow lava WHILE it was actively forming underwater during a volcanic eruption in Hawaii. These divers were only a few feet from molten rock, but while it was very hot, they weren't being cooked instantly. The only hazard they faced was when the rock pillows suddenly cooled, they would collapse and implode, causing a very powerfull shock wave in the water. Here's some more modern footage of this at this website.

http://www.oceanfootage.com/stockfootag ... er_Volcano

Lothar wrote:How do deep-water currents behave? We know that hot water, like hot air, will rise (lower density). Eventually, some percentage of the heat released underwater is making it to the surface. The questions at hand:

1) how much of the heat reaches the surface?
2) what area is it spread over (via currents, etc.)?
3) how long does it take?

Leave it to him to ask informed questions.

Map of arctic ocean currents. Note in center it appears that currents remain locked in a circular pattern that may keep any volcanic heat trapped:

http://maps.grida.no/go/graphic/ocean_c ... ice_extent

Here's an interesting take I found on a \"web log\":

http://strata-sphere.com/blog/index.php/archives/5589

tunnelcat wrote:Water is a very good insulator...

Granted water doesn't conduct heat even remotely as well as say silver or copper (or diamond which is practically on a scale of its own), however it does conduct heat many times better than air. Perhaps you were referring to the large heat capacity of liquid water negating the volcanic activity? Because the oceans are able to absorb a nearly unfathomable amount of energy before warming any significant amount.

See: http://en.wikipedia.org/wiki/Thermal_co ... uctivities

There's two questions that are so important that I'm surprised it hasn't even been asked yet.

When was the last eruption and is the volcano still active?

Ferno wrote:There's two questions that are so important that I'm surprised it hasn't even been asked yet.

When was the last eruption and is the volcano still active?

Sounds like a ongoing process:
"But along most of the mid-ocean ridge -- including the Gakkal Ridge -- the plates are pulling apart, allowing molten magna and gases trapped beneath the crust to escape."

It's not ongoing, it happened 1999 to 2001 (they assume). They have found evidence of it, not exploding volcano's and are now exploring the idea that this may be more common than expected (this wasn't a slow leak like the footage posted above, it was more of a gas explosion as I understand it).

http://www.sciencedaily.com/releases/20 ... 140649.htm

PS I think this is a weak argument against man-made climate change effecting the polar ice pack. Underwater volcano's are far more common than above ground ones (earths surface=mostly ocean) and this ice has been intact for millions of years.

What ever happened to the \"global cooling\" scare that was going on a decade or 3 ago? Plus most scientists agree that \"global warming\" is bogus.

http://www.heartland.org/Article.cfm?artId=11548

sorry andy, but I look at that article and I just shake my head.

Andy wrote:Plus most scientists agree that "global warming" is bogus.

No... no they don't. Even your own article only said 17,000 scientists did.

Sorry I do not understand ANY argumentation in direction like \"global warming is bogus\".

Because:
1) Many scientists say it's not
but what is more important to me
2) Even if it MIGHT BE, does that give us the right to give a ★■◆● about pollution and our environment?

Somehow I do not care about the \"we have to...\" or the \"we still need...\". Let's just face it: If we go on like that, some day we'll pay for it. Maybe our children or their children, but someone will pay for this.

Andy wrote:Plus most scientists agree that "global warming" is bogus.

I find that statement totally laughable. Global warming is not bogus, it's an indisputable fact. Look at the temp data from the last 120 years. The earth is getting warmer. You can’t argue with that.

Now, what is arguable is whether we humans are causing it or not. I think that is the real debate.

We humans are pumping a tremendous amount of known greenhouse gases into the atmosphere. Can the earth absorb and process what we are giving it? I don’t really know, but I personally think that we aren’t helping.

TIGERassault wrote:

Andy wrote:Plus most scientists agree that "global warming" is bogus.

No... no they don't. Even your own article only said 17,000 scientists did.

There aren't many actual scientists are on that list. It's an infamous petition. Andy's link is from 2003, and if anything, climate change has happened far faster than we imagined five years ago.

While the petition has been portrayed by global-warming skeptics as authoritative evidence that many scientists reject the catastrophic scenario of global climate change, Robinson acknowledged that little attempt was done to verify credentials of those who responded.

Several environmental groups questioned dozens of the names: "Perry S. Mason" (the fictitious lawyer?), "Michael J. Fox" (the actor?), "Robert C. Byrd" (the senator?), "John C. Grisham" (the lawyer-author?). And then there's the Spice Girl, a k a. Geraldine Halliwell: The petition listed "Dr. Geri Halliwell" and "Dr. Halliwell."

The actual consensus looks more like this list. I'm not sure why this conversation is still going on? We see the effects of climate change on the news every day. It doesn't really matter whose fault it is at this point, what is matters is what can we do to save our skins?

Krom wrote:Granted water doesn't conduct heat even remotely as well as say silver or copper (or diamond which is practically on a scale of its own), however it does conduct heat many times better than air. Perhaps you were referring to the large heat capacity of liquid water negating the volcanic activity? Because the oceans are able to absorb a nearly unfathomable amount of energy before warming any significant amount.

Yeah, technically that wasn't a very good use of the word "insulator", but I used that term because water's large heat capacity essentially makes it BEHAVE like an insulator for all intensive purposes in the SHORT term. It will absorb a lot of heat before it begins to warm up and transfer that energy to it's surroundings. That's why I referred to the long time it takes to heat water on the stove. In the LONG term however, given enough constant heat input, it will begin to warm up and transfer heat outward to it's surroundings. If the volcanic eruptions at the bottom continued for a long period of time, years maybe, or especially increased in area or output, then we might see the ocean above begin to warm up and melt some ice.

I'm of the opinion that air temperature is probably responsible for the Arctic ice melting. Even though air is a poor conductor of heat, it is being applied over a large area and thus can have more impact on ice temperature. Whether the Arctic ice melting is caused by 'Global Warming' or just normal climate variation over time might be a moot point. The ice up north (and in Antarctic as well) has been melting at an accelerated rate in the past decade and continues to do so. This will have a considerable impact on all of our lives since it will directly affect the oceans and thus the rest of the planet's climate. If there is even a 'microscopic' chance that we humans are partially responsible for this climate warming, shouldn't we err on the safe side and be proactive in trying to save our planet by cutting back on carbon production? The side benefits of this action, like cleaner and healthier air and reduced burning of fossil fuels, would be good for all life on Earth.

Well, to be on the \"safe side would be costly:

Reducing U.S. carbon dioxide emissions to 7 percent below 1990’s levels by the year 2012--the target set by the Kyoto Protocol--would require higher energy taxes and regulations causing the nation to lose 2.4 million jobs and $300 billion in annual economic output. Average household income nationwide would fall by $2,700, and state tax revenues would decline by $93.1 billion due to less taxable earned income and sales, and lower property values. Full implementation of the Kyoto Protocol by all participating nations would reduce global temperature in the year 2100 by a mere 0.14 degrees Celsius.

Actually JFTR, ice already sitting in water will not displace any more water if it melts, only ice on land can displace water if melted.

Just wanted to point that out.

But I agree we should err on the side of caution, but I just wish we could avoid all the hyperbole. (and the economic fallout)

Spidey wrote:Actually JFTR, ice already sitting in water will not displace any more water if it melts, only ice on land can displace water if melted.

When an ice cube (or an iceberg, which is a big ice cube) floats in water, then by definition the weight of the ice cube is exactly equal to the buoyancy force, which is equal to the weight of the displaced water.

When the ice cube melts, its volume changes, but its weight is conserved (law of the conservation of mass). So the melted water from the ice cube has exactly the same weight as the water that was displaced by the ice cube when it was frozen -- therefore the volume of melted water fits exactly in the previously displaced volume -- and the water level stays the same.

Note that this argument applies only if the ice cube is made of the same water as the water that it is floating in. This is true, for example, with the Arctic ice pack, which is made of frozen sea water. However, it is not true for Antarctic icebergs, which are blocks of fresh-water ice from the continent that are floating in salt-water sea. In this case, we must take into account that the salt water is denser than the fresh water. The fresh-water iceberg still weighs as much as the weight of the displaced salt water, but because of the difference in density, the volume of melted fresh water will be slightly greater than the displaced volume of salt water -- so when the iceberg melts, the water level will rise, although the difference is very small.

If the ice is melting due to a rise in temperature of the water, then the water level might rise because of thermal expansion - related to, but not because of, the ice melting.

http://www.seed.slb.com/qa2/FAQView.cfm?ID=1166

So, of course the real danger is melting from Antarctica and Greenland, but since the topic was the Arctic, I thought I would point that out.

Ferno wrote:When an ice cube (or an iceberg, which is a big ice cube) floats in water, then by definition the weight of the ice cube is exactly equal to the buoyancy force, which is equal to the weight of the displaced water.

What if the iceberg was radioactive, and it's half-life was exactly the amount of time it took to melt, and was made of a substance that had the same density as the water? How much mass would be converted to energy compared to the mass of the iceberg? (This assumes that matter does not have mass, that the water's coefficient of friction is -0.92, that the water starts at rest, and the iceberg's initial velocity is 4.0 m/s up, the iceberg's escape velocity is 0.2 m/s, and it's final speed is 2.0 m/s in a low-earth orbit, that it fails an orbital transfer, lands in the sun anyway, and ends its journey at rest. A force of 10000000 Newtons then acts randomly on the earth, causing it to be wrenched out of orbit, and everyone dies, except the geckoes. A random airplane falls out of the sky with at an angle of 35.9 degrees above the horizontal, and impales itself on the moon. The geckoes then go to Mars in a submarine, traveling at 35000000 m/s underwater. The Earth plummets into the sun, with a velocity of 3.5 m/s along the frictionless ramp. Everyone is reincarnated, and they promply die again. The only thing that survives is a copper wire with a cross-sectional area of 0.1 m and a resistivity equal to hydrogen. Find the power of the circuit, measured in nanowatts. Determine how long it will take the earth to become a plasma, assuming it has matter, but no mass. Determine the exact date and time the Earth falls into the sun, assuming the sun's gravitational field is equal to 0 Newtons per Coulomb. Air resistance does apply.)

LOL @ radioactive iceberg.

Seems like you're using technobabble to obfuscate the fact that you don't want scientific principles getting in the way of ideology.

Alter-Fox wrote:wall of text

You lost me at "radioactive iceberg".

Narfig_Agar wrote:It's not ongoing, it happened 1999 to 2001 (they assume). They have found evidence of it, not exploding volcano's and are now exploring the idea that this may be more common than expected (this wasn't a slow leak like the footage posted above, it was more of a gas explosion as I understand it).

Do try and think a bit clearer. Separating tectonic plates are continuously active magma producers. Also read the part where they said the area in question has active volcanoes that are miles wide in size. Operative word being "active".

Edit add from OP"
""Both sonar and visual images showed an ocean valley filled with flat-topped volcanos up to two kilometres (1.2 miles) wide and several hundred metres high." "

woodchip wrote:

Narfig_Agar wrote:It's not ongoing, it happened 1999 to 2001 (they assume). They have found evidence of it, not exploding volcano's and are now exploring the idea that this may be more common than expected (this wasn't a slow leak like the footage posted above, it was more of a gas explosion as I understand it).

Do try and think a bit clearer. Separating tectonic plates are continuously active magma producers. Also read the part where they said the area in question has active volcanoes that are miles wide in size. Operative word being "active".

Edit add from OP"
""Both sonar and visual images showed an ocean valley filled with flat-topped volcanos up to two kilometres (1.2 miles) wide and several hundred metres high." "

Sorry, Firefox and I don't see the word "active" in the article. Could you quote it? Secondly, just because it's a volcano, doesn't mean it's spewing magma or will ever spew again (see Hawaii)

DarkHorse wrote:

Alter-Fox wrote:wall of text

You lost me at "radioactive iceberg".

It was just a messed up physics problem. The point was to use something from every unit of Physics I studied this year, in a way that made no sense. (For instance, Newtons per Coulomb is used to measure electric fields, not gravitational fields.)

Narfig_Agar wrote:

woodchip wrote:

Narfig_Agar wrote:It's not ongoing, it happened 1999 to 2001 (they assume). They have found evidence of it, not exploding volcano's and are now exploring the idea that this may be more common than expected (this wasn't a slow leak like the footage posted above, it was more of a gas explosion as I understand it).

Do try and think a bit clearer. Separating tectonic plates are continuously active magma producers. Also read the part where they said the area in question has active volcanoes that are miles wide in size. Operative word being "active".

Edit add from OP"
""Both sonar and visual images showed an ocean valley filled with flat-topped volcanos up to two kilometres (1.2 miles) wide and several hundred metres high." "

Sorry, Firefox and I don't see the word "active" in the article. Could you quote it? Secondly, just because it's a volcano, doesn't mean it's spewing magma or will ever spew again (see Hawaii)

Perhaps instead of having others do your searching for you, you might try exhibiting a little scientific curiosity. This will be the last time I do so:

"The scientists had expected that the Gakkel ridge would exhibit "anemic" magmatism. Instead, surprisingly strong magmatic activity in the West and the East of the ridge and one of the strongest hydrothermal activities ever seen at mid-ocean ridges were found. These results require a fundamental rethinking of the mechanisms of seafloor generation at midocean ridges (Nature, January 16 and June 26)." Link is from 2003

"Current theories of oceanic crustal production predict that volcanic activity deminishes as the spreading rate of the tectonic plates decreases and only little or no hydrothermal activity. Instead, the scientists found high levels of volcanic activity. "We expected the volcanic activity to gradually decrease from West to East as the magmatic systems shut down. Instead, approximately in the middle of the survey area, the magmatism shut down completely, then dramatically increased," says Dr. Jonathan Snow, the leader of the research group from the Max Planck Institute."

"Hydrothermal hot springs on the seafloor were also far more abundant than predicted. "We expected this to be a hydrothermally dead ridge, and almost every time our water measurement instrument came up, they showed evidence of hydrothermal activity, and once we even 'saw' an active hot spring on the sea floor," noted Jonathan Snow. The biologists on the expedition theorize that Arctic hydrothermal vent communities have been cut off from the rest of the worlds oceans for long periods of time, and may have conserved archaic forms"

http://tinyurl.com/2tngph

Now, take your liberal biased nay saying elsewhere.

woodchip wrote: Perhaps instead of having others do your searching for you, you might try exhibiting a little scientific curiosity. This will be the last time I do so:

http://tinyurl.com/2tngph

Ahhh, a new link! I'm not about to pursue a degree in underwater geothermal studies for an internet discussion. Regardless, there's no indication that this is a new situation, simply a newly discovered one. Trying to link it to climate change is tenuous at best.

woodchip wrote:Now, take your liberal biased nay saying elsewhere.

I see.

Ferno wrote:LOL @ radioactive iceberg.

Seems like you're using technobabble to obfuscate the fact that you don't want scientific principles getting in the way of ideology.

No, I was just in a silly mood, and everyone here was so serious. Besides, when I'm in university next year, virtually all the courses I'll be taking are science courses. (I'm planning for a career in genetics, although I haven't figured out exactly what it will be yet.)