Thoughts from the 28th Century: June 2014

Saturday, June 14, 2014

Solar Cycles, part fou

This is part four of a series of posts about climate change. This post also tells how we really should correct for climate change.

I was told that I should write on Climate Change again. I complained that I already had done so enough, but I couldn’t think of anything better to write about, so I looked into the periodicity of climate change. It is a very interesting subject, and there is more to be done with it, but there isn’t enough data for everything to be put together in a neat, compact essay, and the scientists have the same problem. There are several types of variation in solar heating of the Earth; some are effects of the Earth’s orbit, while others are matters of the Sun. These three cycles are called Milankovitch cycles.

Over time the Earth’s orbit becomes at time rounder and at other times more eccentric (more elongated). The elongation results in greater differences in temperatures from season to season; right now the orbit is relatively round.

Then there is axial tilt (obliquity). Now the Earth’s axis tilts about 23.5 degrees from vertical. Over time the tilt has been as little as 22.1 degree. The difference isn’t huge, but less axial tilt leads to colder temperatures near the poles, because lees sunlight reaches that region during Summer.

Then we have precession, the angle of the tilt with respect to the place in orbit. At present the tilts most away from the Sun near the Winter Solstice, when the Earth is closer to the Sun. This leads to less heating of the major landmasses.

We all know about the sunspot cycle. Sunspots go from maximum to minimum in an eleven year cycle. Temperatures tend to be higher during sunspot maxima.

There are several other cycles of varying length but of less well-known origins. http://en.wikipedia.org/wiki/Solar_variation . .

Cycle length	Cycle name	Last positive carbon-14 anomaly	Next "warming"
232	--?--	AD 1922 (cool)	AD 2038
208	Suess	AD 1898 (cool)	AD 2210
88	Gleisberg	AD 1986 (cool)	AD 2030

Plus the 2,300 years: Hallstatt cycle, the 6000 years (Xapsos and Burke, 2009), and a few others. And some work has been done that indicated that there were harmonic combination of different cycles. There isn’t any sign that anyone has looked into how one cycle affects another, but that is something that probably would happen based on the nature of the different cycles. I couldn’t find anything that indicated a larger cycle in sunspots, something that would account for the various minima and maxima, but there probably is a super cycle, or something else is causing the variations.

I think the total is at least seven cycles. I was going to chart some together, but seven would be too messy to be useful. In addition,

‘The sensitivity of climate to cyclical variations in solar forcing will be higher for longer cycles due to the thermal inertia of the oceans, which acts to damp high frequencies. Using a phenomenological approach, Scafetta and West (2005) found that the climate is 1.5 times as sensitive to 22-year cyclical forcing relative to 11-year cyclical forcing, and that the thermal inertia of the oceans induces a lag of approximately 2.2 (± 2) years in cyclic climate response in the temperature data.[35]” from http://en.wikipedia.org/wiki/Solar_variation

It is quite clear that none of the mechanism that have been proposed for causing climate change are adequate explanations, but the observations cover only a rather short time with any reliability; although we have descriptions of climatic conditions tell a good story for a long time, and we can infer climatic conditions from agricultural outputs for a considerably longer period. Unfortunately, none of the observations match the known cycles; although there is some correspondence with harmonics.

“Perry and Hsu (2000) proposed a simple model based on emulating harmonics by multiplying the basic 11-year cycle by powers of 2, which produced results similar to Holocene behavior. Extrapolation suggests a gradual cooling during the next few centuries with intermittent minor warm-ups and a return to near Little Ice Age conditions within the next 500 years. This cool period then may be followed approximately 1,500 years from now by a return to altithermal conditions similar to the previous Holocene Maximum. [36]”

Even if they did an excellent job we will have to wait to see.

I was hoping that there would be some relationship between sunspots and longer range patterns, but there isn’t. Apparently the relationship is coincidental.

Solar activity events and approximate dates
Event	Start	End
Homeric minimum^[29]	950BC	800BC
Oort minimum (see Medieval Warm Period)	1040	1080
Medieval maximum (see Medieval Warm Period)	1100	1250
Wolf minimum	1280	1350
Spörer Minimum	1450	1550
Maunder Minimum	1645	1715
Dalton Minimum	1790	1820
Modern Maximum	1900	present

Looking at the various cycles, it becomes clear that there probably will not be an especially warm period or an ice age in the immediate future, even though several cycles are pointed toward the ice age. Combining that with the fact that the present level of temperatures in significantly lower than the Medieval Warm Period, it appears that we will continue to have rather normal climate with reason for bitching about the cold of Winter and grousing at the heat of Summer. If you are interested in doing something about that, then you will be interested in my preceding posts, which will discuss triggering a new ice age (it isn’t difficult).

Reversing Global Warming, part three

This is part three of a series of blog posts on reversing global warming. In the first part I proposed trying iron dust on the oceans to cause phytoplankton blooms that would eliminate atmospheric CO2, which would (in theory) reduce global warming. The second method would be to cut down on heating from the Sun. And this third part is about cheaper ways to reduce the amount of sunlight reaching the Earth.

In addition to the methods for shielding the Earth from the radiation from the Sun already mentioned, there are some other methods that are rather time honored. You are probably aware that the Year Without Summer was caused by an eruption of Mount Tambora, a volcano in Indonesia. And more recently Mount Pinatubo in the Philippines caused a slight worldwide cooling when it erupted. I realize that humans don’t have much control over the eruptions of volcanos, but neither have humans tried to set off a volcano, yet.

Volcanos put huge amounts of dust and chemicals into the atmosphere and those can, and do, reflect sunlight. With some careful calculation and playing with fire it should be possible modulate the eruptions of some volcanos. Efforts have already been made to control volcanos, and further research is being conducted, see links below.

If eruptions can be controlled or stopped, then they can be started in a limited way, so that only gases and dust that would decrease the amount of sunlight getting to Earth. We certainly don’t want another Year Without a Summer, but it might be nice to use something that would otherwise be damaging to improve the world.

Research would also have to be done into the amount of material that would have to be teased out of the volcanos. It certainly would depend, in part, on the locations, and each volcano has its particular blend of effluvia. The altitude to which the material would rise would also be an issue. Material that rises to greater heights would tend to stay in the atmosphere longer. Sulfur dioxide is a common component of volcanic gas and it is well known for reflecting sunlight, but some volcanos eject vast amounts of carbon dioxide. It might be necessary to pick and choose and to balance the outputs of different volcanos.

As yet little research has been done into this system for controlling global warming, but there is great potential for research grants. As part of the research it would be a good idea to consider other sources for gases that would reflect sunlight. In recent times industrial gases ejected into the atmosphere included sulfur dioxide in considerable quantity. Industrial operations also produced nitrous oxides, which tend to trap heat, so there was some balancing done; although it was unplanned. Many of the industrial processes that produced relevant gases are still being done, and the waste gas that was formerly released into the atmosphere is now treated and discarded in controlled ways. The controls could simply be removed and the gas allowed to go into the atmosphere.

While that would amount to allowing air pollution, it would be for a good purpose, and it could be regulated. In fact, careful regulation would be necessary to ensure that additional greenhouse gases would not be released into the atmosphere. Laws would have to be changed in most of the world, but it seems that China is already doing its part to reverse global warming by using air pollution. I don’t know if they have improved upon what Western countries did, but it would be worthwhile to ask.

Anyone who lived in a developed country before 1970 surely remembers the clouds of particulates that floated above the cities. Those clouds were composed of a mixture of gases that had little effect on temperature, because some of the particulates and gases were absorbing heat, while others were reflecting the sunlight back into space. We need to specialize and have clouds that only reflect the heat back into space. Water vapor would be ideal, if only it weren’t such a good greenhouse gas. It might be safer to use dust. We might even use some of the iron dust that we would be spreading on the oceans. It the particles were small enough, then they would stay in the stratosphere for years, so did the dust from Tambora.

The choice isn’t obvious. There are downsides for every alternative, but something has to be done. And in our hearts we know what it needed.

http://www.geo.mtu.edu/~hnlechne/controling_eruptions.htm

http://www.geo.mtu.edu/~hnlechne/volcano_engineering.htm

http://www.scienceforums.net/topic/50833-preventing-volcanic-eruptions/

Reversing Global Warming, part two

This is part two of a series of blog posts on reversing global warming. In the first I proposed trying iron dust on the oceans to cause phytoplankton blooms that would eliminate atmospheric CO2, which would (in theory) reduce global warming. The second method would be to cut down on heating from the Sun.

It is obvious that reducing the amount of solar radiation reaching the Earth would lower the temperature of the Earth. My suggestion is not new. Others have suggested shielding the Earth from the Sun, and some have made detailed plans. Basically the shield need not be fancy, and it could be made largely of space junk and rocks. There are some amazingly expensive proposals that have been made. The first proposal linked below would cost only about 350 Trillion dollars; apparently the one who dreamed it up just wanted to be on record as having made such a proposal. The second one isn’t as expensive, and some of the ideas are quite reasonable.

The second proposal might be affordable, and it probably would work quite nicely. It proposes putting a dust cloud around the Earth by turning some asteroids in dust and persuading the dust to flow in the right pattern. Moving the asteroid into a suitable orbit before turning it to dust would work nicely. The proposal would start with a near Earth asteroid, and crush much of that. Then a mass driver would be used to spread the dust. And the remains of the asteroid would become another satellite that would hold the dust in place as the moons of Saturn help to keep the rings in place.

The third proposal has some good and some bad features. It wouldn’t cost all that much. The website doesn’t include a cost estimate, but it would be similar to the cost of a Mars ship. One of the bad points is that a rather large asteroid would be put into a fairly close Earth orbit. A small mistake in placement could result in a large mass dropping to Earth. That might cut down on solar radiation by putting up large clouds of dust from Earth. It might also kill many people, etc.

I think that the easiest way to block sunlight would be something like a window blind in geosynchronous orbit. The blind need not be solid, and it would certainly have to be flexible. It could be made from space junk and material from near Earth asteroids. The exact material would depend on what was available out there, but one side would have to ne reflective. If it weren’t reflective, then it would become rather hot, because there would be nothing to conduct the heat away, so it would have to radiate away, and that might not be reliable. It might also be possible to convert the heat to electricity. There already are many things in geosynchronous orbit, so we would have to put this at a different distance, but it could house communications and other facilities; it would even be possible to put a few hotels along the blind to help to defray the cats of construction, and the NSA would love to have it as a listening post.

The concept is simple, but estimating the cost will have to wait until we decide on the placement and size of the shield. The location will be important, because there are so many things in orbit already, and we would have to avoid interfering with those. When the shield will be completed, it can replace many satellites, but until then it will have to be out of the way. Another consideration is the latitude at which it would orbit, or if it would have a sinusoidal orbit. Having it at high latitudes would block sunlight to a larger area, and that might be desirable, but the reduction in temperature would be more noticeable at lower latitudes. Its effects would be more lasting in the higher latitudes also, because the icepack and glaciers would hold the cold for a long time. That location of it would also make it more like correcting the axial tilt of the Earth. A shield just a thousand miles wide could put the entire Polar Regions into permanent darkness and cold. The only downside would be that the scientific station at the South Pole would become less useful. But all of Antarctica would become dark, so it would be less useful for all purposes.

We will have to make a decision. There is something to be said for all of the shields, but I will present other alternatives in part three.

Comments and suggestions are solicited.

First sunshield proposal

http://www.telegraph.co.uk/earth/environment/globalwarming/4839985/Scientists-to-stop-global-warming-with-100000-square-mile-sun-shade.html

Second

http://www.sciencemuseum.org.uk/climatechanging/climatescienceinfozone/exploringourfuturechoices/3point7/3point7point1.aspx

Third

http://www.space.com/17830-asteroid-dust-geoenineering-global-warming.html

Reversing Global Warming, part one

People are always talking about the weather, but I am proposing that we do something about it. This is the first of three (or maybe more) posts about reducing reversing global warming.

People have been talking and writing about global warming since they stopped talking about the next ice age; that was around 1980. SO far it has all be words. It climate scientists are so sure that human activity has been causing a rise in temperatures, then we should correct the damage before it will be too late.

According to the climate scientists atmospheric CO2 is the thing that has caused rising temperatures, so we should bring the CO2 down to pre-industrial levels, and one method for doing that has been known since back when climate scientists were talking about the new ice age that was about to start. There were articles about how cooling started, and one of the theories was that seeding the oceans with iron would cause plankton blooms that would soak up CO2, and shrimp and other small animals would eat the plankton and multiply, thus exhaling CO2, so there would be no net change in the amount of atmospheric CO2, except for that carbon that would fall to the bottom of the ocean when the predators defecated. More recently it has been theorized that iron rich dust blown from deserts blowing into the oceans led to ice ages during the last four million years. (See link below)

People have, as the linked article states, tested part of this by spreading iron dust on the ocean. That has resulted in plankton blooms, as one would expect. But no one has dumped in enough iron to change the atmosphere at all. If the theory is correct, then a billion tons of iron dust would be enough to remove a substantial amount of CO2 from the atmosphere.

Even though a billion tons may seem like an amazingly large amount of iron, it isn’t all that much. Consider that a 10x10 steel I-beam weighs about fifty pounds per linear foot, so a billion pounds would translate to twenty million linear feet of bean, and if we cut the beam into forty foot sections, then there only be five hundred thousand beams, or the amount in a small city.

The iron would have to be ground rather finely. Single celled animals would have to eat the dust, and it would have to be light enough that it could float on a breeze. For that reason the iron would have to be ground to that small size. It wouldn’t make much difference whether the iron were pure or oxidized, so we could grind up ore very finely and use that, rather than wasting refined metal. There would be extraneous material in the ground ore, but that wouldn’t hurt, and it might help. U.S. production of iron ore is about two billion metric tons annually, so a twenty-five percent increase for two years would produce all of the iron dust we would need. If that schedule became a problem, then we could stretch production over another year or two. And, if it turned out that applications of iron dust would have to continue, it could become a permanent industry.

The actual schedule would have to be determined by experiments that have not yet been done that would show whether continued applications of iron dust were necessary and whether the applications would be continuous or periodic. Pouring on too much might just result in the extra sinking to the ocean bed.

Another thing that we don’t know is whether the iron dust causing a phytoplankton bloom causing a drop in CO2 levels would have immediate effects. As we can see from last fifteen years increases in CO2 do not cause immediate temperature rises, and the same may be true of decreases on CO2 levels. We also do not know whether the increase in animals that would eat the phytoplankton would have any effect.

It might be wise to regard the first ten years of applying iron dust to the ocean as an experiment to see whether it would be effective. An alternative theory about atmospheric CO2 and climate is that the CO2 is an effect of increasing temperatures, rather than a cause. I won’t argue this position, because we should be planning to test the theory.

http://www.newscientist.com/article/mg21128245.000-ironrich-dust-fuelled-4-million-years-of-ice-ages.html#.U5W45qyznvM

I’ll present another method next time.