Technology on an Earth Scale.....Hmm, not sure about this...

Mark Twain once said "Climate is what we expect, weather is what we get."

Some say Methane is going to be a bigger problem compared to CO2 from the 
climate change perspective. Others say climate change would come from other 
sources etc etc....So if we spend trillions of dollars on a technology for a 
specific problem, what assurance do we have that some other problem will not 
come and hit us while we are not looking?

Besides human 'intervention' (in environment/social) IS the problem. Why 
should one believe that it takes human intervention to solve a problem 
caused by human intervention?

However, from a technical point of view, 'prevention is better then 
cure'....so isn't the money better spent on alternative energy sources etc 
etc.

So perhaps the title should be changed from
"How Earth-Scale Engineering Can Save the Planet"      TO
"How Earth-Scale Engineering Can CHANGE the Planet" again!

peace
yunus


>From: Chris Keene <[log in to unmask]>
>Reply-To: Chris Keene <[log in to unmask]>
>To: [log in to unmask]
>Subject: [Fwd: Popular Science: How Earth-Scale Engineering Can Save the 
>Planet]
>Date: Sat, 20 Aug 2005 06:22:10 +0100
>
>Does anyone have any thoughts on these ideas?  They seem pretty crazy to 
>me, but I'm not an expert, and it might be useful for us to have some 
>evaluation of them in case we ever get to debate them with their supporters
>
>Chris
>
>-------- Original Message --------
>Subject: 	Popular Science: How Earth-Scale Engineering Can Save the Planet
>Date: 	Thu, 11 Aug 2005 21:24:13 +0100
>From: 	Chris Keene <[log in to unmask]>
>To: 	chris keene <[log in to unmask]>
>
>
>
>How Earth-Scale Engineering Can Save the Planet
>
>
>
>David Keith never expected to get a summons from the White House. But in 
>September 2001, officials with the President’s Climate Change Technology 
>Program invited him and more than two dozen other scientists to participate 
>in a roundtable discussion called “Response Options to Rapid or Severe 
>Climate Change.” While administration officials were insisting in public 
>that there was no firm proof that the planet was warming, they were quietly 
>exploring potential ways to turn down the heat.
>
>Most of the world’s industrialized nations had already vowed to combat 
>global warming by reining in their emissions of carbon dioxide, the chief 
>“greenhouse gas” blamed for trapping heat in Earth’s atmosphere. But in 
>March 2001 President George W. Bush had withdrawn U.S. support for the 
>Kyoto Protocol, the international treaty mandating limits on CO2 emissions, 
>and asked his administration to begin studying other options.
>
>Keith, a physicist and economist in the chemical and petroleum engineering 
>department at the University of Calgary, had for more than a decade been 
>investigating strategies to curtail global warming. He and the other 
>scientists at the meeting—including physicists from Lawrence Livermore 
>National Laboratory who had spent a chunk of their careers designing 
>nuclear weapons—had come up with some ideas for “geoengineering” Earth’s 
>climate. What they proposed was tinkering on a global scale. “We already 
>are inadvertently changing the climate, so why not advertently try to 
>counterbalance it?” asks retired Lawrence Livermore physicist Michael 
>MacCracken, a former senior scientist at the U.S. Global Change Research 
>Program who helped organize the meeting.
>
>“If they had broadcast that meeting live to people in Europe, there would 
>have been riots,” Keith says. “Here were the bomb guys from Livermore 
>talking about stuff that strikes most greens as being completely wrong and 
>off-the-wall.” But today, a growing number of physicists, oceanographers 
>and climatologists around the world are seriously considering technologies 
>for the deliberate manipulation of Earth’s climate. Some advocate planetary 
>air-conditioning devices such as orbiting space mirrors that deflect 
>sunlight away from Earth, or ships that intensify cloud cover to block the 
>sun’s rays. Others are suggesting that we capture carbon dioxide—from the 
>air, from cars and power plants—and stash it underground or react it with 
>chemicals that turn it to stone.Carbon dioxide wasn’t always public enemy 
>number one. For the past 400,000 years, the concentration of CO2 in the 
>atmosphere has fluctuated between about 180 and 280 ppm (parts per million, 
>the number of CO2 molecules per million molecules of air). But in the late 
>1800s, when humans set about burning fossil fuels in earnest, atmospheric 
>CO2 began to increase with alarming speed—from about 280 ppm to the current 
>level of almost 380 ppm, in a scant 100 years. Experts predict that CO2 
>could climb as high as 500 ppm by 2050 and possibly twice that by the end 
>of the century. As CO2 levels continue to rise, the planet will get hotter. 
>“The question now,” says Ken Caldeira, an atmospheric scientist at Lawrence 
>Livermore and one of the world’s leading authorities on climate change, “is 
>what can we actually do about it?” Here are some of the geoengineering 
>schemes under consideration.
>
>1. Store CO2 Underground
>Feasibility: 10
>Cost: $$
>RISK: 4
>In the southeastern corner of Saskatchewan, just outside the town of 
>Weyburn—the “Opportunity City”—a steel pipeline descends 4,000 feet below 
>the prairie at the edge of a 70-square-mile oil field. Into this 
>subterranean cavern, petroleum engineers are pumping 5,000 tons of 
>pressurized, liquefied carbon dioxide every day. The aim is twofold: Use 
>high-pressure CO2 to drive oil from the porous rock in the reservoir to the 
>surface, and trap the carbon dioxide underground.
>
>Welcome to the world’s largest carbon-sequestering operation. Dubbed the 
>Weyburn Project, it began in July 2000 as a partnership between EnCana, a 
>Canadian oil and gas company, and Canada’s Petroleum Technology Research 
>Centre. With $13 million in funding from more than a dozen sponsors, 
>including the U.S. Department of Energy, engineers have already socked away 
>six million tons of carbon dioxide, roughly the amount produced by burning 
>half a billion gallons of gasoline.
>
>The Timeline
>Unlike other geoengineering schemes, this one is already happening, with 
>more than half a dozen major projects under way. The problem, says Howard 
>Herzog, a principal research engineer at MIT’s Laboratory for Energy and 
>the Environment, is that concentrated CO2 is in short supply. There’s too 
>much of the gas floating around in the air, but actually capturing, 
>compressing, and transporting it costs money. In the U.S. and most other 
>nations, there are no laws requiring fossil-fuel-burning power plants—the 
>primary source of CO2 emissions—to capture a single molecule of the gas.
>
>The Promise
>By 2033, the Weyburn Project will store 25 million tons of carbon dioxide. 
>“That’s like taking 6.8 million cars off the road for one year,” says 
>project manager Mike Monea, “and this is just a pilot test in a small oil 
>reservoir.” Saline aquifers, giant pools of saltwater that have been 
>trapped underground for millions of years, could hold even more CO2. Humans 
>dump about 28 gigatons of CO2 into the atmosphere every year. Geologists 
>estimate that underground reservoirs and saline aquifers could store as 
>much as 200,000 gigatons.
>
>The Perils
>Before CO2 is injected into the ground, it’s compressed into what’s called 
>a supercritical state—it’s extremely dense and viscous, and behaves more 
>like a liquid than a gas. In this form, CO2 should remain trapped 
>underground for thousands of years, if not indefinitely. The danger is if 
>engineers accidentally “depressurize” an aquifer while probing for oil or 
>natural gas. There’s also a risk that carbon dioxide could escape slowly 
>through natural fissures in subterranean rock and pool up in basements or 
>cellars. “If you walked down into a basement [full of CO2],” Keith says, 
>“you wouldn’t smell it or see it, but it would kill you.”
>
>2. Filter CO2 from the air
>Feasibility: 4
>Cost: $$$
>RISK: 4
>Klaus Lackner is accustomed to skeptics. They’ve doubted him since he first 
>presented his idea for extracting carbon dioxide from ambient air in March 
>1999, at an international symposium on coal and fuel technology. “The 
>reaction from everyone there was utter disbelief,” recalls Lackner, a 
>physicist with the Earth Engineering Center at Columbia University.
>
>He called for the construction of giant filters that would act like 
>flypaper, trapping CO2 molecules as they drifted past in the wind. Sodium 
>hydroxide or calcium hydroxide—chemicals that bind with carbon 
>dioxide—would be pumped through the porous filters much the way antifreeze 
>is circulated through a car’s radiator. A secondary process would strip the 
>CO2 from the binding chemical. The chemical would recirculate through the 
>filter, while the CO2 would be set aside for disposal.
>
>The Timeline
>Lackner is collaborating with engineer Allen Wright, who founded Global 
>Research Technologies in Tucson, Arizona. Wright is developing a 
>wind-scrubber prototype but remains tight-lipped about the project. He 
>estimates that a completed system is at least two years away.
>
>The Promise
>Wind scrubbers can be placed wherever it’s convenient to capture carbon 
>dioxide, so there’s no need to transport it. Lackner calculates that a wind 
>scrubber designed to retain 25 tons of CO2 per year—the average amount each 
>American adds to the atmosphere annually—would require a device about the 
>size of a large plasma-screen television. A single industrial-size wind 
>scrubber about 200 feet high and 165 feet wide would snag about 90,000 tons 
>of CO2 a year.
>
>The Perils
>Some experts are dubious about the ease of separating carbon dioxide from 
>the binding chemical, a process that in itself would require energy from 
>fossil fuels. “CO2 is so dilute in the air that to try to scrub from it, 
>you have to pay too much for energy use,” Herzog says. And to capture all 
>the carbon dioxide being added to the atmosphere by humans, you’d need to 
>blanket an area at least the size of Arizona with scrubber 
>towers.3.Fertilize the ocean
>Feasibility: 10
>Cost: $
>RISK: 9
>On January 5, 2002, Revelle, a research vessel operated by the Scripps 
>Institution of Oceanography, left New Zealand for the Southern Ocean—a belt 
>of frigid, stormy seas that separates Antarctica from the rest of the 
>world. There the scientists dumped almost 6,000 pounds of iron powder 
>overboard and unleashed an armada of instruments to gauge the results.
>
>The intent was to test a hypothesis put forth by oceanographer John Martin. 
>At a lecture more than a decade ago, Martin declared: “Give me a 
>half-tanker of iron, and I will give you an ice age.” He was alluding to 
>the fact that the Southern Ocean is packed with minerals and nutrients but 
>strangely devoid of sea life. Martin had concluded that the ocean was 
>anemic—containing very little iron, an essential nutrient for plankton 
>growth. Adding iron, Martin believed, would cool the planet by triggering 
>blooms of CO2-consuming plankton.
>
>Oceanographer Kenneth Coale, who directs the Moss Landing Marine 
>Laboratories near Monterey, California, was a chief scientist on the 
>Southern Ocean cruise. He says the project was a success, proving that 
>relatively small quantities of iron could spawn colossal blooms of 
>plankton.
>
>The Timeline
>Scientists are wary, saying that too little is known about the deep-ocean 
>environment to endorse further large-scale experiments. In October, Coale 
>and other scientists will gather in New Zealand for a weeklong meeting 
>sponsored by the National Science Foundation, New Zealand’s National 
>Institute for Water and Atmosphere, and the International 
>Geosphere-Biosphere Programme to decide how to proceed.
>
>The Promise
>Iron fertilization is by far the cheapest and easiest way to mitigate 
>carbon dioxide. Coale estimates that just one pound of iron could 
>conceivably hatch enough plankton to sequester 100,000 pounds of CO2. “Even 
>if the process is only 1 percent efficient, you just sequestered half a ton 
>of carbon for a dime.”
>
>The Perils
>“What is still a mystery,” Coale says, “is the ripple effect on the rest of 
>the ocean and the food chain.” One fear is that huge plankton blooms, in 
>addition to gorging on CO2, will devour other nutrients. Deep currents 
>carry nutrient-rich water from the Southern Ocean northward to regions 
>where fish rely on the nutrients to survive. Says Coale, “A fertilization 
>event to take care of atmospheric CO2 could have the unintended consequence 
>of turning the oceans sterile. Oops.”
>
>4. Turn CO2 to Stone
>Feasibility: 7
>Cost: $$
>RISK: 3
>The Grand Canyon is one of the largest carbon dioxide repositories on 
>Earth. Hundreds of millions of years ago, a vast sea covered the land 
>there. The water, rich in carbon dioxide, slowly reacted with other 
>chemicals to create calcium carbonate, or limestone—the pinkish bands 
>striping the canyon walls today.
>
>Nature’s method for turning CO2 to stone is achingly slow, but researchers 
>at the Goldwater Materials Science Laboratory at Arizona State University 
>are working on a way to speed up the process. Michael McKelvy and Andrew 
>Chizmeshya use serpentine or olivine, widely available and inexpensive 
>minerals, as feedstock to fuel a chemical reaction that transforms CO2 into 
>magnesium carbonate, a cousin of limestone. To initiate the reaction—known 
>as “mineral carbonation”—the CO2 is compressed, heated, and mixed with 
>feedstock and a catalyst, such as sodium bicarbonate (baking soda).
>
>The Timeline
>Scaling up the process to handle millions of tons of CO2 would require huge 
>quantities of serpentine or olivine. A single mineral-carbonation plant 
>would carve out a mountain, but, McKelvy says, “You could carbonate [the 
>CO2] and put it right back where the feedstock came from.”
>
>The Promise
>Mineral carbonation is simply an accelerated version of a benign natural 
>process. The limestone in the Grand Canyon is 500 feet thick, McKelvy says, 
>“and it has been sitting there not bothering anybody for millennia.”
>
>The Perils
>It costs roughly $70 to eliminate one ton of CO2, a price that McKelvy says 
>is too high. Also, the feedstock and CO2 must be heated to high 
>temperatures. “You wind up having to burn fossil fuels in order to provide 
>the energy to activate the mineral to put away the CO2,” he says.5. Enhance 
>Clouds to Reflect Sunlight
>Feasibility: 6
>Cost: $$
>RISK: 7
>Some proposed solutions to global warming don’t involve capturing carbon 
>dioxide. Instead they focus on turning down the heat by deflecting or 
>filtering incoming sunlight.
>
>On any given day, marine stratocumulus clouds blanket about one third of 
>the world’s oceans, mostly around the tropics. Clouds form when water vapor 
>clings to dust or other particles, creating droplets. Seeding clouds with 
>tiny salt particles would enable more droplets to form—making the clouds 
>whiter and therefore more reflective. According to physicist John Latham, a 
>senior research associate at the National Center for Atmospheric Research 
>in Boulder, Colorado, boosting reflectivity, or albedo, in just 3 percent 
>of marine stratocumulus clouds would reflect enough sunlight to curb global 
>warming. “It would be like a mirror for incoming solar radiation,” Latham 
>explains.
>
>Latham is collaborating with Stephen Salter, an emeritus professor of 
>engineering design at the University of Edinburgh, who is making sketches 
>for GPS-steered wind- powered boats that would cruise the tropical 
>latitudes, churning up salt spray. “I am planning a flotilla of unmanned 
>yachts sailing backward and forward across the wind,” Salter says. “They 
>would drag propellers through the water to generate electricity, which we’d 
>use to make the spray.”
>
>Salter wants to outfit each boat with four 60-foot-tall Flettner rotors, 
>which look like smokestacks but act like sails. An electric motor starts 
>each rotor spinning, which, along with the wind, creates a pressure 
>differential (less pressure in front of the rotor, more in back), 
>generating forward thrust. From the top of the rotor, an impeller would 
>blast a fine saltwater mist into the air.
>
>Until the concept is tested, Salter isn’t sure exactly how many ships would 
>be needed to mitigate global warming. “Maybe between 5,000 and 30,000,” he 
>says. That may sound like a lot, but Salter notes that for World War II, 
>the U.S. built nearly 100,000 aircraft in 1944 alone.
>
>The Timeline
>Latham initially raised the notion in a 1990 paper. “The article went down 
>like a lead balloon,” he says. But early last year in England, at a 
>geoengineering conference hosted by MIT and the Tyndall Centre for Climate 
>Change Research, he presented the concept again. “The consensus was that a 
>number of ideas originally thought to be outlandish were deemed 
>sufficiently plausible to be supported further. Our work fell into that 
>category.” Latham needs a few million dollars to test his idea. “On the 
>scale of the damage that will be caused by global warming, that is utterly 
>peanuts.”
>
>The Promise
>What’s nice about this idea is that it can easily be fine-tuned. “If we 
>tried it and there was some deleterious effect, we could switch it off, and 
>within four or five days all evidence would have disappeared,” Latham says.
>
>The Perils
>One worry is that although the tiny salt particles released by evaporating 
>sea mist are perfect for marine stratocumulus-cloud formation, they are too 
>small to create rain clouds. “You might make it harder for rain to form,” 
>Salter says. “Therefore, you would not want to do this upwind of a place 
>where there is a bad drought.”
>
>6. Deflect Sunlight With A Mirror
>Feasibility: 1
>Cost: $$$$
>RISK: 5
>One of the most ambitious schemes is a giant space “mirror” positioned 
>between the Earth and sun to intercept sunlight. To build the mirror, 
>physicist Lowell Wood, a senior staff scientist at Lawrence Livermore, 
>proposes using a mesh of aluminum threads that are only a millionth of an 
>inch in diameter and a thousandth of an inch apart. “It would be like a 
>window screen made of exceedingly fine metal wire,” he explains. The screen 
>wouldn’t actually block the light but would simply filter it so that some 
>of the incoming infrared radiation wouldn’t reach Earth’s atmosphere.
>
>The Timeline
>Wood, who has been researching the mirror idea for more than a decade, says 
>it should be considered only as a safety net if all other means of 
>reversing global warming “fail or fall grossly short over the next few 
>decades.”
>
>The Promise
>Once in place, the mirror would cost almost nothing to operate. From Earth, 
>it would look like a tiny black spot on the sun. “People really wouldn’t 
>see it,” says Michael MacCracken. And plant photosynthesis isn’t expected 
>to be affected by the slight reduction in sunlight.
>
>The Perils
>Wood calculates that deflecting 1 percent of incoming solar radiation would 
>stabilize the climate, but doing so would require a mirror spanning roughly 
>600,000 square miles—or several smaller ones. Putting something that size 
>in orbit would be a massive challenge, not to mention exorbitantly 
>expensive.
>
>
>Copyright © 2004 Popular Science
>A Time4 Media Company All rights reserved. Reproduction in whole or in part 
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