Pulsating climate

This is a pure bit of speculation.  If true, climate change will result, at least for the transition period, in very cold winters in America, Canada and Eurasia and very hot summers.  First a few facts (or at least accepted theories).

The Gulf Stream which brings warm water along the surface of the ocean from Florida towards the North Atlantic is powered primarily by the freezing out of fresh water ice from sea water in the Arctic and North Atlantic oceans.  Left behind is cold, saltier water which sinks and flows south along the bottom of the ocean.  Water is pulled north to replace this water.

The water which is being pulled northward is saltier than deeper water because of evaporation in the tropics but doesn't sink because it is warmer.  As it flows north, it cools and at some point is heavy enough to sink.  This positive feedback adds more power to the Gulf Stream.

As sea ice (and land ice for that matter) melts, it freshens the surface water in Northern latitudes and so when freezing starts, it will take longer before the resulting water is salty enough to sink. A big influx of fresh water into the North Atlantic should weaken the push that powers the Gulf Stream.

Ice is and insulator.  If you have open water in contact with cooler air, the water gives up its heat to the air, sinks and warmer deeper water replaces it.  The heat exchange between open water and the air is large and heat is being replaced on the surface by convection.  Once you have a cover of ice this convective process is greatly slowed.  Heat has to pass through the ice into the air in order to cool the water in contact with the bottom of the ice.  The thicker the ice the greater the "R" value of the ice.  ie, the slower the flow of heat between water and air.

As climate change continues, the time of net melting becomes earlier* and the time at which freezing exceeds melting is later.    The freezing period shortens, the melting period lengthens.  Here is where the speculation starts.

*Oddly enough over the past few years, the date at which melting starts has been getting later.

I wonder how long the delay is between the start of freezing and hence the sinking of salty water and the increase in flow of the Gulf Stream.  There should be a couple of factors in play here.  First it is a huge body of water to get moving with huge inertia so there should be a delay between push and move.  Think of a huge weight on one of those frictionless pads when you start to push it.  At first the motion is barely perceptible but builds up as you continue pushing.  Similarly, stop pushing and it takes the weight a long time to stop moving.

Secondly, it takes time for the warm salty water from the Florida region to move far enough north on the weakened Gulf Stream where it can cool enough to sink and add it's power to the Gulf Stream.

What strikes me as possible, is as the period of freezing shortens and the period of melting lengthens, we could reach a point where the push (cold salty water sinking) and the result (the Gulf Stream getting up to speed) could be 6 months out of sinkronicity.  We would end up with  a fast flowing Gulf Stream in the summer bringing warm water to the North Atlantic along with warm temperatures and, probably, heavy rain followed by a stalled Gulf Stream in Winter giving us really harsh winters.  Harsh winters would result in lots of freezing of fresh water ice from sea water, giving a push to the Gulf Stream.  It's effect would be felt next summer.

For those who suggest that this will lead to another ice age, remember, it doesn't matter how much snow falls in the winter or how cold it is.  An ice age can only start if the snow last through the summer.  In the above scenario, no snow would last through the summer.  In fact, the remaining glaciers should melt away with all the bad consequences this would bring.

Does anyone know if the flow of the Gulf Stream pulsates in any sort of annual cycle at present.

Post script:   A thought just occurred to me.  During this period of transition to a warmer climate in which the Arctic becomes largely ice free in the fall but freezes during the winter, the push to the Gulf stream should be shorter but sharper.  Clearly the ice starts to freeze later than previously but without a thick cover of ice, the transfer of heat to the atmosphere and the radiation of heat into space is more rapid.  It is possible that the rate of freezing and hence the rate of production of cold, heavy, salty water would be greater than when there is already a thick layer of insulating ice covering the ocean.  The length of the push is shorter but more intense.  How would this effect the whole system??

Floating villages

For some reason, I have always been fascinated by the thought of a floating village.  My interest was re-triggered by watching the amazing U-tube item on the chap, Richard Sowa, who built an island in a bay in Cancun, Mexico, which floats on plastic bottles held in bags of fishing net.  Have a look at this amazing video.

What a great idea.  I have often thought that the ideal place to put a floating village would be right in the middle of one of the Oceanic gyres.  Everything that floats finds its way into these areas and stays there. This is due to Coriolis.  In a clockwise rotating gyre in the Northern Hemisphere, to-the-right is into the centre.   It is not certain that a floating village that sticks up into the air would behave in the same way as something that is almost completely submerged; that it would say in the gyre but I think there is a pretty good chance it would.  Worth a try. 

An added advantage of this location is that these gyres are full of the necessary building material to build the floats on which the village would sit.  Tons and Tons of plastic waste are caught in these gyres.  There is a technique *  for melting unsorted plastic waste into  viscous liquid that can be injected molded into whatever form one wishes.  UV resistant chemicals would have to be added.  Better still, the link talks about the use of solar energy to accomplish this.  One little fly in the ointment is that all the pieces of plastic trapped in the ocean gyres of the world will have a film of organic material on them and often various fouling organisms.  One might have to find a way to clean the plastic before it could be used.

* Scroll down to the item on plastics in the above link.

I picture floats of, say, the size of a dining room table linked with flexible couplings to adjacent floats with a plastic factory chugging away, turning out new floats.  Rubber tires might make the ideal link as they are in great supply and themselves float if they are placed upright to trap air.    They are almost indestructible.  As the floats are finished, they would be fastened to the island which just grows and grows.  The plastic melt can also be extruded rather than injected molded to make a wide variety of construction materials.  You can have solid rods, pipes, I beams, U beams or any other form you wish.  As the floating island becomes large enough you would add an extruder and manufacture light, strong members for the skeletons of your buildings.  You might be able to extrude the material with closed bubbles, making all the elements of the structure buoyant.

Note that it is sunny most of the time in the oceanic gyres, giving the likelihood of lots of available solar energy.

In case you are picturing a sterile sort of environment like the one in the movie 1984, look at the first link.  Richard planted Mangroves on his bottle-supported-island which grew very quickly with, of course, its roots in sea water and had various drums and pots growing tomatoes and other vegetables.  So what would the people do on this floating island.  Not everything could be produced on the island and it would be valuable to have an export product to trade for goods from the mainland.

My first thought is oysters and specifically the Pacific oyster.  The main reason that this came to mind is that I used to grow them as one of the crops of a mariculture farm.  Oysters need plankton to grow and diatoms are the best plankton.  So how do we grow plankton in the sunny but oligotrophic* water of the gyres of the world.

* Very poor in nutrients

The answer is to access the cold, nutrient rich water below the thermocline.  This is found at around 300m  in many tropical oceans and here we can use the wave action to do the pumping.  While there is not much weather in the center of the gyres, waves are sent across the oceans from all around.  By the time they reach the gyre centre, they are pretty gently rolling swells but that is just fine for our pump.  Black Polypropylene pipe is almost the same density as sea water.  If you put a weight on one end of, say a 400 or 500m piece of pipe, it will hang vertically in the water with only the mass of the weight you put on the bottom needing to be supported on the surface.  The pipe itself is virtually weightless in water.   So we connect this pipe to a float and attach a right angle at the top which feeds into a pipe that goes to our mariculture unit.  Now all we need is a one way valve somewhere in the pipe which allows water up but not down.  As a swell lifts the float and with it the pipe, the whole column of water is given an upward momentum (along with the pipe which is moving upwards at the same speed).  As the trough drops the float, the weight pulls the pipe down, the water continues up as the one way valve opens and water pours up the pipe.  If you need more water, you put down another inexpensive pipe.  So what do we do with this water.

Once we have this nutrient rich water in the euphotic zone, and remember, the centre of gyres are almost constantly sunny, Algae blooms just take off.  Almost certainly, there would be some phytoplankton in the water that would inoculate the process but if not, it is easy enough to inoculate the water. You might have to add a little water glass to the incoming water to encourage diatoms, perhaps not.  If so, water glass is cheap.  There might be a need for a little Iron salt too.  Apparently ocean water is quite poor in Iron.  So where does this water go.

To grow diatoms we need to hold this cold deep water in the euphotic zone for one to two days.  So in our float system, we leave a space and put in a membrane, shaped like the nets that salmon farms * use to grow salmon.  Essentially a pond. We attach it so that the rim is above the sea and organize the outlet so that the water in the pond is, say, 10cm above sea level.  The slight resulting 'head' (pressure) is what keeps the "pond" inflated.

*ps.  I have a lot of reservations about salmon farms which are actually feed lots, not farms,  but the video does show what sort of set up could be used in a floating oyster farm.

From the phytoplankton pond, the water flows through similar structures in the form of a trough with racks of oysters in the water stream.  The cycle for oysters is about 9 months in these types of conditions from spat to commercial size.  Oyster spat can be obtained from a variety of hatcheries around the world and could very easily be produced on our island.  The system is not complicated at all.  So what about the water that leaves the oyster troughs.

The oysters have utilized the plankton and mineralized* the nutrients they don't use.  The nutrients are in the ideal form to be taken up by macro algae (seaweed) of which many varieties have a good market.  Think of the seaweed that is wrapped around Sushi or the sea weeds from which Carageenan or Agar are refined.  Growing sea weed has the added advantage of removing nutrients from the water before it is returned to the ocean.

* Turned them back into simpler compounds.

You might wonder where the fresh water will come from for drinking, cooking and growing plants.  Fortunately we have the cold water from the depths to use. Water from 400m is about 7 degreesC.  Water from the surface, 25 degrees or more.  Using a bit of the electricity from the solar panels to power a vacuum pump, you can make the surface water in a closed vessel boil and it can be condensed using the deep cold water in a heat exchange.  It is possible that Multi-Stage flash distillation would be the most efficient option.  Experts in the field would be able to design the best system. With the humid air of the gyre, you might even be able to condense water out of the air using the cold deep water.  Ideally, you would use the cold of the deep water to make fresh water and discharge the warmed sea water into your mariculture system.  What else could the village do.

One of the most lucrative activities would be tourism.  Complete isolation, great sea food and warm tropical waters to swim in (inside a net to keep the sharks out) would be very attractive plus the completely unique nature of the vacation.

Since we are creating a mid ocean mini upwhelling, a unique assemblage of animals would likely develop around the village.   The village would act like a FAD (Floating Agrigation Device).  The village could also rent out space to one of the marine research institutions of the world such as Woods Hole or Scripts.   

One problem would be what to do with human waste, vegetable scraps, chicken manure and so forth.  Whatever portion of this the community felt comfortable with could be turned into compost via a worm farm to be used in growing vegetables but the rest could be turned into biogas which is about 70% methane and 30% Carbon dioxide.  Biogas can be used for cooking or for heating the plastic making equipment. It can also be used to run a diesel generator.  After the biogas has been generated, the remaining material still has all the necessary nutrients for gardening.

The key to this idea is developing a system that can turn contaminated plastic into durable floats which can be linked to make a large platform.  If the plastic units can be manufactured so that the material itself is lighter than water, so much the better.   

Of course, a floating village does not have to depend on plastic floats.  One could make them out of a variety of materials and even cement.  It would be, though, at the very least psychologically  nice to have floats that would continue to float even if filled with water.  This leaves the possibility of patching up a hole, bailing the float out and continuing to operate.  Nothing wrong with a combination too.  The first floats might be commercially made to form the nucleus of the village followed by the utilization of plastic trapped in the gyre.