Transcript:
The most widely disseminated possible consequence of Global Warming is a shift in the course of the Gulf Stream that triggers an Ice Age that sweeps suddenly across the Northern Hemisphere with catastrophic affects. Deep ocean currents of fresh water from glacial melt change the salinity and density of sea water in ways that effect the regional thermodynamic fluid flow. Thus, thermal transport currents like the Gulf Stream can change direction rapidly as the whole system moves from one equilibrium state to another. If you have ever seen the smoke streaming up from a cigarette in an ashtray suddenly change direction in a room where the air is very still, you have witnessed this effect in action. The mechanical analog is a long slender object, like a book, standing momentarily on edge before a breeze tips it over. The equilibrium forces can be out of balance for an undetermined period of time before finally reaching the critical stage or “tipping point” were the object falls over. The concern of scientists about an “imbalance” comes from the fact that once the hammer falls, there is no way to stop it. Unfortunately for us, there is a wild card in this mix of thermodynamic fluid forces that we may have no control over.
The Earth's magnetic field has weakened and changed polarity many many times over the life span of our planet. It's called Geomagnetic Reversal. The shortest of these polarity flips is called an excursion and takes at the least two hundred some odd years and will remain flipped for at least 400 years, so it's not a sudden change that can happen any second. No, it's a meandering process that involves a slow movement and weakening of the poles. In fact, the process can take as long as ten thousand years and the polarity will remain in that state for as long as a million years. The last time the poles flipped was about 41,000 years ago during the last ice age. Interestingly, the farthest extent of glaciation during that period was 22,000 years ago, or about 19,000 years after this last Geomagnetic polarity change.
In spite of the fact that it is a polar solvent with a magnetic dipole, pure water is diamagnetic and a dielectric. Throw in a few ions like Na+ and Cl- and it acts like a pretty good conductor. When ever a conductor moves in a magnetic field, an electric field forms that produces a counter magnetic field. This is called the Lorentz Force. This force can act like a brake, slowing the momentum or changing the direction of ocean currents. This last statement may seem like a no-brain-er to some, but finding corroboration on the internet could be difficult. In any case, it is an established fact that the Earth's magnetic field is weakening and shifting. At the very least, this shift may affect thermal mixing of the oceans. At the most, entire currents like the Gulf Stream may change course in unexpected ways, with unexpected results.
This video by Rafael Gontijo shows how thermal mixing of a ferromagnetic fluid is affected by a magnetic field. Clearly, the oceans are much larger, more complex, and not, strictly speaking, composed of ferromagnetic material. However, this video makes the kind of fluid flow effects easier to see.
Now, the Earth's magnetic field is small, between 30 micro-Teslas at the Equator and 60 micro-Teslas at the poles. However, this is enough of a field to produce ion separation, electric currents, and therefore measurable opposing magnetic fields in the ocean currents. So, it's not really much of a stretch to imagine that the momentum of these currents may also be affected. Not only that, but the atmosphere may also be directly affected in the similar ways. The composition and phase of the atmosphere is largely different from the ocean but similar effects of braking and course deflection may be at play.
First, consider that clouds contain ions produced from dissolved Sulfur oxides, nitrogen oxides, sea-salt, not to mention dissolved Carbon dioxide, and other stuff. So we should expect the same kinds of ion deflection in cloud movement as we see in ocean currents. This basically boils down to faster spinning and more quickly moving storm systems in the absence of a magnetic field. Hurricanes and tornadoes, for example, may become even more severe, and less predictable.
Second, diatomic oxygen is para-magnetic. Meaning that it is slightly attracted to the poles of a magnet. This means that cold air currents flowing south will have more momentum and warm lower pressure north flowing air currents will have less momentum. Bare in mind that high pressure and lower altitude translates in to a higher percentage of oxygen, and thus, more magnetic force per unit volume than higher altitude and lower pressure air masses. Not only that, but the force acts in the same direction as the magnetic field lines, as opposed to the perpendicular force exerted on ocean currents and storm clouds. This dynamic would necessarily lead to heavier rain and snow because it would facilitate the transport of moisture. Frontal boundaries may also become more and more vertical and farther reaching. It is this far reaching north south moisture transport, I believe, that may responsible for creating an ice age.
John Holdren, Science Adviser to President Obama has several videos on The Daily Conversation channel of YouTube that explains the consequences of Global Climate Change. “The Polar Vortex Explained in 2 Minute” at http://www.youtube.com/... shows how the polar vortex weakens and becomes more jagged with deeper excursions of cold air south and warm air north. This means more extreme rain, snow, and drought events in the northern hemisphere. We can only imagine that the effect of a weaker magnetic field will only exacerbate the problem. The question is, will any of this lead to a new ice age? And, is there a relationship between changes in the Earth's magnetic field and glacial periods? It may only be a coincidence that the last magnetic field flip occurred right in the middle of our last glacial period. Our climate is effected by a vast matrix of forces. It goes without saying that the big picture needs a lot of well trained eyes to interpret it. Let's just hope that we have the will to turn that knowledge into action.
Sources and Links below the fold.
Citations:
Best illustration of concept "Thermomagnetic convection" by Rafael Gontijo
Here is an interesting theory about how magnetic fields are generated on the daily mail:
http://www.dailymail.co.uk/...
Magneto hydrodynamics:
http://en.wikipedia.org/...
Search key words (gulf stream moves south)
Scientists uncover diversion of Gulf Stream path in late 2011
http://phys.org/...
NASA image of Atlantic current flowhttp://www.giss.nasa.gov/...
GULF STREAM chart
http://www.nature-education.org/...
Animation of flow
http://www.dailymail.co.uk/...
Thermohaline circulation
http://geography.about.com/...
Is the Gulf stream moving:
http://www.eupedia.com/...
BBC on climate change and the GS
http://www.bbc.co.uk/...
GS moves north in 2011
http://news.discovery.com/...
http://www.dailykos.com/...
Gaurdian measured slowdown of current from africa feeding lower GS.
http://www.theguardian.com/...
Pole shift:
Pole shift map
http://www.earthweek.com/...
Pole shift accelleration over time
http://www.whatdoesitmean.com/...
http://en.wikipedia.org/...
Interesting article about chelating molecules used to make magnetic materials.
http://www.tandfonline.com/...
Lumpy gravity:
http://blogs.discovermagazine.com/...
Ocean currents Advected by magnetic field: (florida current)
http://www.aoml.noaa.gov/...
http://en.wikipedia.org/...
http://www.livescience.com/...(effects of flip-Live Science)
Separation of gaseous materials using a magnetic field. Called"Open Gradient Magnetic
Separation"-OGMS-
http://pe.org.pl/...
Magnetic effect of ocean flow - map of magnetic field variations in ocean
http://www.newscientist.com/...
revealed.html#.U3bu3_ldWSo
Ocean circulation generated magnetic signals
http://www.terrapub.co.jp/...
Major water transport of oceans and magnetic field -Vivier et al 2004 Through the Drake Passage
Effect of Drake Passage on the global thermohaline circulation (southern hemisphere)
http://www.gfdl.noaa.gov/...
John Holdren science advisor to President Obama "The Polar Vortex explained in 2 minutes"
http://www.youtube.com/...
These fluctuations in Earth's magnetic field are known as secular variation.
http://news.nationalgeographic.com/...
Thermomagnetic convection
http://youtu.be/...
Mr. Temme convection demo with red food coloring
http://www.youtube.com/...
Bad astronomer channel--stand egg on end
http://www.youtube.com/...
Nekoosa Water Tower Drop
http://www.youtube.com/...
http://thumbs.dreamstime.com/...
http://www.iceagenow.com/...
http://www.school-for-champions.com/...
http://www.school-for-champions.com/...
http://i.huffpost.com/...
http://www.school-for-champions.com/...
http://static.ddmcdn.com/...
Cloud ions
http://2.bp.blogspot.com/...
corielis effect
http://classconnection.s3.amazonaws.com/...
http://coe.kean.edu/...
Global air circulation
http://www.indiana.edu/...
http://upload.wikimedia.org/...
heavy rain and snow flooding
http://i.telegraph.co.uk/...
big wave
http://i.dailymail.co.uk/...
http://www.baynews9.com/...
http://www.beyoubesure.org/...
Dark ice
http://static-1.nexusmods.com/...
description
Tue May 20, 2014 at 6:49 AM PT: Not rigorous or peer reviewed but interesting nevertheless.
here is another experiment I did in my studio. Bear in mind the magnetic field here is probably somewhat less than 90 degrees from the actual angle of incidence of the Earth's magnetic field.