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Post by sigurdur on Jan 28, 2015 4:18:34 GMT
news.yahoo.com/watch-1-000-foot-high-wave-move-across-233828437.htmlRight now, two research vessels carrying some 40 marine scientists are battling stormy conditions in the Tasman Sea to learn more about gigantic subsurface waves—some 1,000 feet high—that are critical to both ocean health and accurate climate modeling. These internal ocean waves form, move, and break just like the ones you see crashing at your favorite beach, only bigger, slower, and very deep down—so deep that no disturbance may register on the sea surface.
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Post by magellan on Jan 29, 2015 0:21:08 GMT
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Post by nautonnier on Feb 1, 2015 11:45:56 GMT
news.yahoo.com/watch-1-000-foot-high-wave-move-across-233828437.htmlRight now, two research vessels carrying some 40 marine scientists are battling stormy conditions in the Tasman Sea to learn more about gigantic subsurface waves—some 1,000 feet high—that are critical to both ocean health and accurate climate modeling. These internal ocean waves form, move, and break just like the ones you see crashing at your favorite beach, only bigger, slower, and very deep down—so deep that no disturbance may register on the sea surface. I am surprised that anyone is surprised. Fluid flowing over an uneven surface leads to 'waves' well who would have thought it?  Watch a stream with ripples showing on the surface from subsurface rocks. Look at orographic clouds, mountain waves and rotor streaming winds from hills, lenticular clouds hundreds of miles away from the mountains that originally caused them. ALl standard fluid behavior. Rossby waves have been known in the oceans for some time. These oceanic waves also can be at depth below the thermocline and travel very slowly with Pacific transit times in years. What is surprising is the amplitude of these waves in the Yahoo news item, and that they have not been discovered before. Or perhaps they have but were deemed uninteresting as there was not very much disturbance at the surface. There seems to be an assumption of deep oceans being relatively placid. But one wonders what the effect of these slow moving waves have with interference and beat frequencies. Could there be the occasional times when the beat frequencies result in sudden and unexplained large ocean disturbance? Could the effects lead to a higher stochastic variability in the thermohaline current than would be expected. |
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Post by sigurdur on Feb 1, 2015 15:20:27 GMT
That was my 1st thought Nautonnier. The fluid dynamics of a very deep wave, the mixing properties etc.
The question I still have is "What is the origin of the energy that supplies the force of this type of wave?"
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Post by icefisher on Feb 1, 2015 17:24:14 GMT
That was my 1st thought Nautonnier. The fluid dynamics of a very deep wave, the mixing properties etc. The question I still have is "What is the origin of the energy that supplies the force of this type of wave?" One physical mechanism I can think of is super cooled waters on frigid ice free seas and the brine that falls to the bottom after being squeezed out of millions of square km of freezing ice. The effect can be observed by slowly pouring very cold colored water into a clear container of warmer clear water. Especially large deep formation zones are found in the north and south Atlantic. I have never seen the cold colored water mix evenly even in a still container of water. Other than the general tendency to sink and spread across the bottom there are always clouds of colored water rising above the bottom. Mix in the elasticity of water and persistent wind directions around antarctic and may be the explanation for why everything moves in one direction. Add to this the ridge between South America and the West Antarctic peninsula and you have a natural wave forming bottom feature. These bottom features create upwelling zones as well where nutrient rich bottom waters rise to the surface and provides the explosion of life seen in these upwelling zones (no doubt primarily from the carbon rich acidic man devouring waters rising to the surface /s)  |
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Post by sigurdur on Feb 1, 2015 17:33:30 GMT
I understand currents and their potential origin pretty well. These waves have to break off said currents then, and then continue onward. The energy expended to move that much water over 1,000's of miles is truly huge.
Think of throwing a rock in a pond. The ring effect, as the rock sinks, is noticeable. But it dispels quickly. The kinetic energy in that rock, say a 20# rock, is substantial. Throw it at something solid and it would vibrate. Now think of the energy required to move that ring 1,000's of miles. Almost mind boggling.
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Post by icefisher on Feb 1, 2015 20:39:44 GMT
I understand currents and their potential origin pretty well. These waves have to break off said currents then, and then continue onward. The energy expended to move that much water over 1,000's of miles is truly huge. Think of throwing a rock in a pond. The ring effect, as the rock sinks, is noticeable. But it dispels quickly. The kinetic energy in that rock, say a 20# rock, is substantial. Throw it at something solid and it would vibrate. Now think of the energy required to move that ring 1,000's of miles. Almost mind boggling. Gravity works very strongly against surface waves because of the difference in density between the atmosphere and the water of the ocean. Yet a storm off New Zealand will deliver large surf to southern California. Indeed the wind energy that forms say 50 foot swells is huge but after traveling thousands of miles they may still be 8 feet or more. Underwater waves running the thermocline have very little gravity working against them because of the miniscule difference in density between the water just above and below the thermocline. Upwelling deep cold currents would only be limited in height by the gravity difference of the water above. I wouldn't have imagined 1000 foot high waves but it might not be so far fetched. |
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Post by greyviper on Feb 4, 2015 1:40:39 GMT
I just wonder what's so interesting about foot high waves. Doesn't they occur most of the time? I mean not, what harm can it do to our oceans?
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Post by sigurdur on Feb 4, 2015 2:42:34 GMT
I just wonder what's so interesting about foot high waves. Doesn't they occur most of the time? I mean not, what harm can it do to our oceans? These are waves that are 1,000's of feet in height Greyviper. |
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Post by greyviper on Feb 12, 2015 16:12:43 GMT
I just wonder what's so interesting about foot high waves. Doesn't they occur most of the time? I mean not, what harm can it do to our oceans? These are waves that are 1,000's of feet in height Greyviper. Oh I see, these are indeed gigantic waves. But precisely, what sort of danger does it pose to our marine ecosystem? |
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Post by nautonnier on Feb 12, 2015 18:08:44 GMT
That was my 1st thought Nautonnier. The fluid dynamics of a very deep wave, the mixing properties etc. The question I still have is "What is the origin of the energy that supplies the force of this type of wave?" I think the origin may be the lunar tides if they get in synch with a particular wave in a current you may not need a lot of extra energy once the systems moving. Like gently taping a pendulum if the tapping frequency matches the period of the pendulum then it will start to swing and a kick at the right time will accelerate it. |
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Post by sigurdur on Feb 12, 2015 18:29:21 GMT
That was my 1st thought Nautonnier. The fluid dynamics of a very deep wave, the mixing properties etc. The question I still have is "What is the origin of the energy that supplies the force of this type of wave?" I think the origin may be the lunar tides if they get in synch with a particular wave in a current you may not need a lot of extra energy once the systems moving. Like gently taping a pendulum if the tapping frequency matches the period of the pendulum then it will start to swing and a kick at the right time will accelerate it. Interesting concept, but not sure the harmonics work on that. Even through a fluid, a continuous wave of this size requires a lot of energy. Think of a water hose, put a 1/2 inch water hose a 1,000' long. Turn on the water. You might have to wait weeks to see a drop exit the hose. Even in fluid, there is friction. |
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Post by nautonnier on Feb 12, 2015 21:59:48 GMT
I think the origin may be the lunar tides if they get in synch with a particular wave in a current you may not need a lot of extra energy once the systems moving. Like gently taping a pendulum if the tapping frequency matches the period of the pendulum then it will start to swing and a kick at the right time will accelerate it. Interesting concept, but not sure the harmonics work on that. Even through a fluid, a continuous wave of this size requires a lot of energy. Think of a water hose, put a 1/2 inch water hose a 1,000' long. Turn on the water. You might have to wait weeks to see a drop exit the hose. Even in fluid, there is friction. True - how many weeks wait are there in thousands of years since the moon started orbiting? |
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Post by icefisher on Feb 12, 2015 23:35:48 GMT
That was my 1st thought Nautonnier. The fluid dynamics of a very deep wave, the mixing properties etc. The question I still have is "What is the origin of the energy that supplies the force of this type of wave?" I would say a combination of the wind, coriolis effect, tides, and thermohaline convection loops. all these forces are largely in the same direction, especially in the oceans surrounding antarctica. I suggested a home experiment. Take one of those concentrated water enhancers. I am not sure if the water enhancers are more dense than water or the same, but you can make them more dense by cooling the enhancer in the refrigerator. When you pour the water enhancer into a glass of water the enhancer rapidly sinks to the bottom, spreads out across the bottom, and mostly rises up the other side and comes back across the glass to where the liquid is being placed in the glass like a wave of colored water. Apparently gravity is all you need. one might think that the heavier water would layer on the bottom but there is constant mixing going on for whatever reason though the water in the glass appears still except for the moving clouds of cool colored water. thermohaline convection loops maybe just one means of driving these waves when you have a variety of geographic features and some water moving at different speeds. It should be an interesting study regarding how it varies over the seasons and year to year |
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Post by greyviper on Feb 16, 2015 15:51:22 GMT
I think we should not be anymore surprised to discover gigantic waves, or should I say huge and subtle movements of water currents undersea. Its good there are not over the water currents. A lot of forces affect these, some are already there by nature and have their own uses most probably. I don't really see anything disadvantageous or harmful related to this phenomenon.
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