An idea for surviving future storms: Raise coast

The San Antonio Express reports on a wizard wheeze to raise the coastline to combat "more frequent, intense storms and the kind of devastation recently seen with Superstorm Sandy" (alright, I know, I know).

People along the coast have a few options in an era of global warming expected to bring more frequent, intense storms and the kind of devastation recently seen with Superstorm Sandy: They can move back from the shore, elevate buildings or build levees to keep the floods at bay.

But a pair of scientists at Georgia Tech and Clemson suggest another alternative, although it sounds a bit like science fiction. Their research shows it is possible to raise the coastline itself.

Yes, it does sound "a bit like science fiction", as do all geo-engineering "wizard wheezes". This one's a real "cracker" - literally.

Leonid Germanovich of Georgia Tech and Lawrence Murdoch of Clemson, both environmental engineers, have worked out the math and are proposing a method of flood protection they call SIRGE, or solid injection for raising ground elevation.

The idea is relatively straightforward. They envision injecting sediment-laden slurry into hydraulic fractures in the ground. If repeated in adjacent areas and over a wide area, it works to push up the surface of the earth. They suggest a series of pumps and wells to force the material underground.

What could possibly go wrong?

After a 1900 hurricane devastated Galveston, Texas, killing an estimated 8,000 people, the city rebuilt after the ground level was raised as much as 17 feet. "It's been shown with the Galveston example, if you can increase elevations, that is your best bet in safeguarding areas against flood," Murdoch said.

While you can't elevate every building in a community, another approach might be to raise the level of the ground below it. A similar technique has been used on smaller scales.For example, when a tunnel is drilled under a city, a technique called compensation grouting is used above it, injecting material to keep the surface above stable so it doesn't sink. Perhaps the best-known example is the grouting done under Big Ben in London when a subway tunnel was built, Germanovich said.

Using SIRGE, the sediment would likely need to be projected 300 or more feet below the surface. The paper suggests that, in theory, at the upper end, it might be possible to raise the coast 10 meters, about 33 feet.

Ten metres? Along the entire coast, and over "a wide area"? Have they worked out just how much "sediment-laden slurry" would be needed, and how many "hydraulic fractures in the ground" would be required? The article does say they've "worked out the math", and presumably are not totally overawed by their figures.

"Fracking" involved in oil and gas extraction costs a lot of dollars, and for all the care taken, results in earth tremors and minor subsidence. If the pumping operations resulted in even a centimetre or so of difference in adjacent ground surface levels, water mains would fracture, roads and buildings and bridges would crack. How could local authorities possibly get permission from all land and building owners? What financial insurance would be needed? The cost of detailed geological surveys to identify possible problem "spots" would be immense.

First floor - future earthquakes, localised subsidence and endless litigation - Going up!

Disconnects in Logic (4) - We don't do Physics

Ever come across the "space mirror"? If not (where were you, on Mars?), let me provide a little illumination. The mirror concept comes in several flavours, from the sublime to the ridiculous single large "sunshade" to trillions (I kid you not) of small sunshades, between the Earth and the life-giving deadly solar rays from our Sun. The intention is to reflect or filter or diffract a portion of the incoming insolation to offset "global warming" caused by life-giving deadly CO2 and other "pollutants" in Earth's atmosphere. Before I continue, I suggest you put down any drink, fragile artefact or large heavy object you might be holding, and swallow anything in your mouth - gum, toothbrushes, pens, thumbs and similar objects excepted - these should be removed. I fear for your safety, dear reader, should you laugh, chortle, guffaw or splutter while reading on.

One of the earliest ideas was for sunshades in orbit around Gaia, a simple and relatively inexpensive concept, one which could be phased over decades, and involve all those countries capable of putting such objects in orbit. International co-operation involving spending large sums is so easy to organise, as we all know. This would cost tens of billions of dollars per year over the coming decades. If you were paying attention, you might have noticed that I referred to this as "relatively inexpensive", which should give you a clue as to the cost of the other schemes. A major disadvantage is of course that roughly half of the orbiting parasols would be on the shady side of Earth at any given time, performing no useful function, and also spoiling things for astronomers beneath. Somewhat disconcertingly (and rather alarmingly) none of the articles I've read mention this problem. Logic disconnect number 1.

Because of the 50% redundancy and consequent additional cost involved, those engineers and scientists who had a well-thumbed copy of "101 things you didn't know about the Solar System" came up with a cunning wheeze to exploit something called a "Lagrange Point". Any object orbiting between the Earth and Sun would have a shorter orbit and greater speed, so would rapidly move away from the Earth, re-visiting in less than a year, if orbiting in contra-rotation (going the other way round) relative to Earth. Johannes Kepler (God rest his soul) discovered this and published his law  in 1619. If the orbiting object is not-too-far from Earth, gravity pulls it back a little, and if the distance is "just right" reduces the orbital speed to keep it stationary relative to the Earth.

Lagrange Points - Source: Montana State University, Department of Physics

L1 is the obviously useful one, the others being most useful if you want to remain a long way from your mother-in-law, though L3 is best to hide from the forces of loranorder. One concept is for a single, large (obviously) "wire mesh" disc at L1, to deflect 1% of the incoming sunlight. Lowell Wood and others have calculated that a screen made of one-millionth of an inch diameter aluminium wire forming a mesh of 1 thousandth spacing would act as a diffraction grating, and "bend" infra-red light away from Earth.

The flies in the ointment are that it must have an area of 1,600,000 sq. km (more than twice the area of Texas) with a diameter of 1427 km, and even with the too-thin-to see wire, with an estimated average mass of 1 gram/sq. metre including "ribs", weigh 1.6 million tons (I'll use the imperial ton,  tonnes are much the same). It's been estimated that using US launch vehicles, the cost of putting anything into Earth orbit is currently $44,000 per kilogram, or $440,000 per ton, and that doesn't include the cost of boosting mirror (parasol or sunshade) parts to the Lagrange point 1.5 m km. further out. Using the space shuttle would cost $175,000 per kilo just to Earth orbit. The mirror would weigh some 1,600,000,000 kilos. Assume the deployment costs reduce tenfold over time and do the sums yourself - I don't think my calculator display is big enough.

Don't employ these guys as fly-swatters because they've missed a few already, as I will show. First, all the diagrams I've seen show the parasol at 90° to the Sun-Earth axis, and the designers and most proponents seem to think it'll stay that way. I have news for them - without giving it a "twist" of one rotation per annum, the parasol would be parallel to the axis in 3 months, having no effect whatever. How it's possible to impart a rotation of exactly 360° per annum to a thinner-than a hair parasol 1427 km across I don't know. Someone suggested a steerable "hub", but hasn't heard of inertia. The parasol might have zero weight but it would have a mass of 1.6 million tons, and it would take some hefty steering jets to shift it. The "ribs" would have to be stiff enough not to flex unduly, adding considerably to the total weight to be lofted from Earth, perhaps doubling it. Brilliant idea, shame about the (lack of) physics. That faint sound is Newton turning in his grave.

There's more (of course there's more!) - the Lagrange points move. The system is not just Sun-Earth, but Sun-Earth-Moon. Objects in space orbit around their centre of mass, not their geometric centres. The centre of mass Sun-Earth is relatively very close to the centre of the sun, but the centre of mass of Earth-Moon (barycentre) is inside the Earth about 1,700 km. below the surface The Earth wobbles slightly therefore, changing the Sun-Earth distance, and also the Moon is either closer to, or further from the Lagrange point as the lunar month progresses. The important L1 and irrelevant L2 are most affected, oscillating by several km a month. In addition, the Earth's orbit ain't a circle but an ellipse, moving closer to, then further away from the parasol, compounding the problem. Our parasol now needs to be moved this way and that constantly to stay close to the elusive Lagrange point L1 and avoid us having to wave goodbye to it, and the trillions of dollars spent getting it up there. Then there's all the inevitable millions of tons of space junk orbiting the Earth at various distances, and the effect of all the CO2 and other gasses emitted during the construction of the parasol, the rockets or shuttles, their fuel, and the burning of that fuel in the atmosphere, none of the aforementioned even hinted at by the rose-tinted spectacle brigade. Unintended consequences, anyone?

The other scheme by astronomer Roger Angel involves 16,000,000,000,000 (16 trillion) pierced transparent 0.6 sq. metre 1-gram discs, forming a cylindrical cloud some 60,000 miles long orbiting in what he calls "L1 orbit". I see several difficulties, quite apart from the obvious, which you should be able to identify for yourselves. First, there's strictly no such thing as "L1 orbit", and even if there was, a 60,000-mile long cylinder oriented towards Earth would leave most of his "flyers" away from that orbit, meaning they'd drift Sunwards or Earthwards, speeding up or slowing down in orbit, and so spreading in all directions. At least he though of the effect of "radiation pressure" which would push the discs earthwards, and introduced a compensating mechanism. The "big parasol" team overlooked this, and also the Solar Wind of atomic particles, which Roger Angel seems to have ignored. Secondly he (Angel) says a 2% reduction in insolation over the entire surface would be "enough to balance the heating of a doubling of atmospheric carbon dioxide in Earth's atmosphere". A reduction of 2% averaged over the surface is around 7 W/m², or twice the IPCC AR4 estimate for a doubling of CO2. That 7 W/m² would be, from what I've absorbed from several years of surfing the net and absorbing concepts of radiative forcing like a solar parasol absorbs sunlight, enough to take the Earth into the next ice-age. Oops. Strong on ideas, short on physics and celestial mechanics, and should read more.

Here's my own "Cool It" plan

I reckon it'd be easier and cheaper just to deposit all that dosh in orbit. A dollar bill has an area of 103.4 sq. cm., and weighs a bit less than a gram, so a trillion of them would cover roughly 10,000,000,000 sq.metres or 10,000 sq. km. and weigh a million tons. Assuming each is oriented at 45° to the Sun on average, the effective area would be around 7071 sq. km. They wouldn't need complicated and expensive rockets, but could be blasted there in "super guns" - quite technically feasible (I know my history). The other advantage is that it doesn't actually cost 1$ to print a 1$ bill. Banknotes are paper and ink, and in some cases include a thin thread of metal (about as thin as the thread of logic in the other schemes). Banks wouldn't have to actually issue the notes as currency.

Each country could contribute a special "Cool It" note, with a picture of the incumbent political leader imprinted thereon. Just think - The US would have "Drill, baby, drill!" Obama waving his birth certificate, the UK would have "The NHS is safe with me" Cameron, Australia could have "No carbon tax" Gillard with a long nose, and Russia would have "It's me again!" Putin. I'm certain both democrats and republicans (though maybe not in equal numbers) would like to see Obama blasted into orbit, and citizens of other countries would be happy to contribute to see their beloved leaders actually doing something useful for a change. A side-advantage is that as the notes drift out of orbit they'd never fall fast enough to burn up, would float to the surface, and still be reflecting sunlight, increasing the albedo. Polar explorers would never run short of toilet paper... the list just goes on. Just think of all the thousands of "green-back" jobs Obama could point to as the election draws nigh. The Pentagon would be allocated funds to develop a "super gun" for the army, and the other services would be green with envy.

There's a Nobel Prize, or at least "Climate Crusader of the Year" in this for me, I'm sure. I may even get my handsome visage (He lies - Ed.) on a special edition banknote and join the political elite in orbit. I've changed my mind - geo-engineering is FUN!

Disconnects in Logic (3) - We don't do Climate

More geo-engineering, I'm afraid, and the inevitable intrusion of the Law of Unintended Consequences (also known as the Law of Human Stupidity and Ignorance, appendix 1). Before it's filed in the "We don't do Climate" garbage bin of history, from the pages of the Toronto Star yesterday (21st Feb):

Global warming: Researchers develop technology to reduce methane gas emissions from oceans

For Stephen Salter and John Latham, there is nothing more deadly than the creation and emission of methane gas.

“It’s 200 times worse than CO2 (carbon dioxide),” Salter, who is emeritus professor of engineering at the University of Edinburgh, said in an interview with the Star.

“It has a quick and serious effect,” Salter said, likening methane to a kind of “crack cocaine” for the atmosphere.

Salter, who works out of the Engineering Design Institute for Energy Systems at the university, was recently in front of a British House of Commons committee on climate change, pleading his case against methane gas. He described its highly destructive impact as it is released from the ocean into the atmosphere, significantly contributing to global warming and the melting of Arctic ice.

"200 times worse than CO2" - just where did he get that from? And their ingenious (if costly) solution?

Salter and his colleague, Latham, who is an atmospheric sciences researcher at University Corporation for Atmospheric Research in Boulder, Co., have come up with what they believe is a solution to the impact of methane on the earth’s environment. They envisage a kind of vessel or land station that sprays salt water into the atmosphere, ultimately affecting the makeup of clouds. The idea is that the clouds could reflect back into space more of the sunlight hitting the ocean.

“We would cool down (the planet),” Salter said.

“We would cool down (the planet)” - indeed? By spraying water vapour, the most powerful greenhouse gas, into the atmosphere? Despite the low temperatures there, a large proportion of the drops would evaporate. A strong dose of reality for messrs. (or is it messers?) Salter and Latham, from the National Snow and Ice Data Center (NSIDC) in Boulder, Colorado.

A case of the vapors 

When it comes to climate change in the Arctic, melting sea ice and warming oceans often get the most attention. Yet in the atmosphere, another watery component is changing as well: water vapor. As sea ice extent and duration decrease and air temperatures rise, the increasingly open Arctic Ocean is subject to even more evaporation, pumping more water vapor into the atmosphere, making it more humid. In addition, warmer air is capable of holding more water, so increasing humidity over the Arctic may be yet another signal that air temperatures in the region are rising, producing yet another feedback mechanism throwing the Arctic climate off-kilter.

More from the article:

Latham worked out that if you increase the number of water drops in a cloud by increasing the condensation nuclei, the cloud will reflect more of the sun’s incoming energy back into the atmosphere, Salter explained. The ocean won’t heat up and won’t release more methane.

There's a very fine balance between "whitening" cloud and triggering precipitation, which not surprisingly reduces cloud, transferring the water to the surface as rain or snow. "Increasing the condensation nuclei" is employed in cloud seeding to induce precipitation. They also have utterly missed the point that increasing snow precipitation would "whiten" the Arctic far better than (possibly) increased cloud would. It might turn out all right in the end, but for the wrong reasons. They've even included a rather bold prediction (make a note in your 10-year diary - it's already in mine)

Without any action on the global warming front, it is predicted that there is a 50 per cent chance that Arctic sea ice will be non-existent in September 2014. If the forecasts are correct, the oceans will heat up even more and the already high levels of methane in the Arctic Ocean will rise even more, Salter said.

If the methane is "in the ocean" how could it possibly increase greenhouse gas warming? Warmer water will hold less methane in solution, not more. Oh - sorry, that quote is from the "loose terminology" department, employed when talking to reporters and dumb amateurs like me. Based on their woolly thinking and focussing on a tiny part of the Arctic climate system, I'd say there's a 100 per cent chance they're off-target by 180 degrees. These "spraying vessels" would be unmanned apparently, and sailing in Arctic waters for months. I can recommend a film for them to view. It's not "An Inconvenient Truth" but "Titanic".

Salter is emeritus professor of engineering at the University of Edinburgh, also known as the "We don't do Climate" department. Latham however, is an "atmospheric sciences" researcher at University Corporation for Atmospheric Research in Boulder, Co. That must be the "CO2 is the most powerful greenhouse gas" department. I was going to add "You couldn't make it up", but they've done all the work for me.

Disconnects in Logic (2) - Can't do the Chemistry

From the wayback machine 21 February, 2003, though he's still "at it" -
Dr Klaus Lackner has the hots for "synthetic trees" to "purify air" as the Beeb has it.

A scientist has invented an artificial tree designed to do the job of plants.

But the synthetic tree proposed by Dr Klaus Lackner does not much resemble the leafy variety.

"It looks like a goal post with Venetian blinds," said the Columbia University physicist, referring to his sketch at the annual meeting of the American Association for the Advancement of Science in Denver, Colorado.

But the synthetic tree would do the job of a real tree, he said. It would draw carbon dioxide out of the air, as plants do during photosynthesis, but retain the carbon and not release oxygen.

Sounds good - we all need the air "purified" of the nasty CO2 we breathe out, but I'm not so sure about that "not release oxygen", so let's get the details

If built to scale, according to Dr Lackner, synthetic trees could help clean up an atmosphere grown heavy with carbon dioxide, the most abundant gas produced by humans and implicated in climate warming.

He predicts that one synthetic tree could remove 90,000 tonnes of CO2 in a year - the emissions equivalent of 15,000 cars.

"You can be a thousand times better than a living tree," he said.

Good-o - I want to be a thousand times better than a living tree, much better than being a thousand times better than a dead one in my opinion (I don't think he meant it that way - Ed.).

For now, the synthetic tree is still a paper idea. But Dr Lackner is serious about developing a working model. His efforts suggest the wide net of ideas cast by scientists as they face the challenge of mitigating climate change.

A "paper idea" - is that anything like a "half-baked" one? Let's hear him out before we jump to conclusions.

The technology calls for two things: seizing carbon and then storing it. Direct capture of CO2, from power plants for example, is the simplest, according to Dr Lackner. But this doesn't work for all polluters. A car can't capture and store its carbon dioxide on-board; the storage tank would be too large.

"It's simply a question of weight," he said. "For every 14 grams of gasoline you use, you are going to have 44 grams of CO2."

The alternative is to capture emissions from the wind. In this case, a synthetic tree would act like a filter. An absorbent coating, such as limewater, on its slats or "leaves" would seize carbon dioxide and retain the carbon.

Dr Lackner predicts that the biggest expense would be in recycling the absorber material.

"We have to keep the absorbent surfaces refreshed because they will very rapidly fill up with carbon dioxide," he said. If an alkaline solution such as limewater were used, the resulting coat of limestone would need to be removed."

My word - the man's a genius - it would take someone with a good knowledge of chemistry and maths to really appreciate this simple but brilliant idea. Luckily I have one I prepared earlier, several decades earlier in fact, and it's me. I've no idea why he picked 14 grams of octane (gasoline), the molecular weight is 114, but neverrmind, 114 grams produces 252 grams, and so 14 grams produces 43.2 grams of CO2. Good enough for a physicist, I suppose, and if the hydrocarbon mix is taken into account I may have to give him credit for accuracy. May, could and might are the three magic words in climate "science" - the universal cop-out. I digress, something I have a perverse liking for, but bear with me, dear reader.

Let's assume that the limewater, a solution of Ca(OH)2 (calcium hydroxide) in water is used as an absorbent. How is this magic CO2 guzzler manufactured? CaO is a constituent of cement for building mortar, and is made by roasting limestone at a very high temperature. Just a mo. - didn't he mention limestone in his last sentence? Indeed he did, so here's a summary of the process. Limestone is burnt in gas-fired rotary kilns, and the resulting calcium oxide is allowed to cool. Water is added (slaking), creating Ca(OH)2 (calcium hydroxide) in solution and releasing some of the heat absorbed in the roasting. Here it is in formulae, and this is the killer:

CaCO3 (limestone) + heat -> CaO (calcium oxide) + CO2

CaO + H2O -> Ca(OH)2

And the "magic tree" CO2 absorbing process:

Ca(OH)2 + CO2 -> CaCO3 + H2O

The net process is therefore:

burn methane (CH4, natural gas) + 3O2 (oxygen) -> heat + CO2

limestone + heat + water -> (less) heat + water + limestone + CO2 (from natural gas)

The only sufficiently large source of calcium on the planet is in the form of limestone or chalk. The growth of plankton with calcium-carbonate based shells or internal skeletons locks up CO2 for millions of years, and our physicist wants to release it to use the rest of the molecule to absorb the same amount of CO2 from the atmosphere, consuming vast amounts of otherwise useful natural gas in the process, and also oxygen from the air to burn the gas, which process itself generates CO2. The outcome is more CO2 than at the start of the entire cycle, and vast quantities of "limestone" sludge. Where to dispose of it - there's always the limestone quarries, which unfortunately won't be big enough, as the limestone now contains a lot of water. He could always dump it in the sea, which is part of the natural limestone/chalk process anyway. Then there's transport costs for CO2-belching trucks, construction costs, environmental damage..... You couldn't make it up.

BTW - if you have any suggestions for Dr Klaus for a "better tree" than his, one that isn't expensive to manufacture, doesn't consume large amounts of valuable energy resource, requires little or no maintenance, is cheap or even free to manufacture, actually removes CO2 from the atmosphere, doesn't spoil the view, and as an added bonus generates oxygen and may even have valuable by-products, please leave a comment, and I'll see if I can let him know about it. I'm still working on it.