Could Geo-Engineering Stave off Climate Disaster?

March 20, 2018

Worthy of discussion, but the scale and possible unforeseen consequences are daunting.

Look for my new video soon which will touch on this. There is still hope that sensible climate action could radically slow, if not stop, melting ice sheets.

Nature:

To stimulate discussion, we explore three ways to delay the loss of ice sheets.

1. Block warm water

The Jakobshavn glacier in western Greenland is one of the fastest-moving ice masses on Earth. It contributes more to sea-level rise than any other glacier in the Northern Hemisphere. Ice loss from Jakobshavn explains around 4% of twentieth-century sea-level rise, or about 0.06 millimetres per year6.

Jakobshavn is retreating at its front. Relatively warm water from the Atlantic is flowing over a shallow sill (300 metres deep) and eating away at the glacier’s base. Making the sill shallower would reduce the volume of warm water and slow the melting. More sea ice would form. Icebergs would lodge on the sill and prop up the glacier.

A 100-metre-high wall with sloping sides of 15–45° could be built across the 5-kilometre fjord in front of Jakobshavn glacier by dredging around 0.1 cubic kilometres of gravel and sand from Greenland’s continental shelf (see ‘Glacial geoengineering’). This artificial embankment, or berm, could be clad in concrete to stop it being eroded. The scale of the berm would be comparable with large civil-engineering projects. For example, ten times more material — 1 cubic kilometre — was excavated to build the Suez Canal. Hong Kong’s airport required around 0.3 cubic kilometres of landfill. The Three Gorges Dam used 0.028 cubic kilometres of cast concrete.

Construction would be arduous and potentially hazardous in cold waters littered with icebergs. The reactions of local people would be mixed: although the project would create employment, large numbers of outside workers would have to be brought in. Ecology, fisheries and tourism could be affected. Glacier sediments supply nutrients for plankton growth, so marine ecosystems would be affected by increased turbulence during construction of the berm and by the loss of sediment once the glacier was slowed.

Building such a berm would tell us whether glacial geoengineering is feasible, or if there would be unanticipated consequences. But the project would have only a small impact on 2100 global sea levels, given that Greenland’s contribution is likely to be just 10–20 centimetres1. Antarctica will be the largest contributor, and geoengineering there will require larger and more challenging projects.

2. Support ice shelves

Where Antarctica’s ice sheets reach the sea, ice flows out as floating shelves. Pinned by rocks and islands, these platforms hold back the glaciers and limit how much ice reaches the sea. As the air and ocean around Antarctica warm, some ice shelves are becoming thinner, particularly those fringing the Amundsen Sea. In 2002, scientists were shocked at the collapse of 3,200 square kilometres of the Larsen B ice shelf, which is now only 30% of the size it was during the 1980s7. Half a dozen other shelves around the Antarctic Peninsula have shattered in the past 30 years.

Sheer cliffs are left behind when an ice sheet collapses. These crumble, accelerating the glacier’s retreat8. The West Antarctic ice sheet is especially vulnerable because its bedrock lies below sea level and is deeper inland9. Warm ocean currents in the Amundsen Sea are melting the bottoms of floating parts of the glaciers, making the sheets more unstable.

The Pine Island3 and Thwaites4 glaciers in West Antarctica are the largest potential sources of sea-level rise over the next two centuries. Both glaciers are losing height and flowing more quickly than two decades ago. Pine Island Glacier reached a flow rate of about 4 kilometres per year in 2009, compared with 2.5 kilometres per year in 199610. Models predict that, by 2150, these two glaciers might disgorge ice ten times faster than current rates, contributing 4 centimetres a year to global sea-level rise8.

One solution is to artificially pin the ice shelves in front of the two glaciers by constructing berms and islands, extended from outcrops or built on the sea floor. For example, the shelf buttressing Pine Island Glacier could be jammed by a berm located on Jenkins Ridge, a high point on the sea bed below the glacier. We estimate that this would require around 6 cubic kilometres of material, or 60 times more than would be needed to plug the Jakobshavn fjord. Relatively small artificial islands in other places — reaching up 300 metres from the sea bed — would require 0.1 cubic kilometres of material each. A large berm (10–50 cubic kilometres) in the open bay could prevent warmer waters from entering.

Whether such engineering feats would successfully delay sea-level rise, and for how long, requires a better understanding of many factors. These include how the ocean circulates below ice shelves; how floating ice fractures and calves icebergs; and how glaciers slide and erode at their bases. A thorough study would be needed to determine the stresses that pinned ice shelves can sustain before they fracture. Models of ice dynamics should determine the most effective locations for pinning.

Material could be shipped to Antarctica from elsewhere in the world, or dredged or quarried locally. But it would be difficult in practice for engineers to work around the ice shelves, which grow and shrink as the glaciers, sheets and conditions fluctuate. Sea ice would also get in the way. Technologies might need to be developed to operate beneath floating ice. Major disturbances to local ecosystems would be expected and would require thorough assessment before and after pinning.

Guardian:

In each case, the team – which includes scientists in Finland and the US – acknowledges that costs would be in the billions. Construction is also likely to cause considerable disruption. For example, building a dam across the Jakobshavn fjord could affect ecology, fisheries and tourism, and large numbers of workers would have to be shipped in to complete the project.

Similarly, building artificial islands in front of glaciers would mean importing about six cubic kilometres of material, a task that would be immensely difficult in stormy Antarctic waters. And drilling through ice that is kilometres thick to pump down cooled water would also stretch the capabilities of engineers.

However, the team insists that such projects should be carefully assessed now as the likely costs appear to be compatible with those of other large energy and civil engineering works being planned across the globe. The issue is simple, they state: should we spend vast sums to wall off all the world’s coasts, or can we address the problem at its source?

“Potential risks, especially to local ecosystems, need careful analysis,” they conclude. “In our view, however, the greatest risk is doing nothing.”

Nature again:

Implementation would require global consent. Antarctica is governed by the Antarctic Treaty, so research there is undertaken within the multilateral framework of the Scientific Committee on Antarctic Research, which meets this June. Countries finance research on the basis of their interests, and a few could take a lead. For example, researchers in China are preparing a $3-billion plan for polar research in the next decade that includes addressing the feasibility of targeted geoengineering schemes such as ours. Options for building a research base in the Hudson Mountains, to access the glaciers flowing into the Amundsen Sea, should be discussed.

Around Greenland, sea levels will fall as ice is lost from its interior, reducing the gravitational pull of the ice sheets. This could be as inconvenient for coastal communities as rising seas. There might be mutual benefits to collaboration between Greenlanders and those who are most at risk of rising sea levels, for example in the small island states of Tuvalu or the Maldives.

Geoengineering of glaciers will not mitigate global warming from greenhouse gases. The fate of the ice sheets will depend on how quickly we can reduce emissions. If emissions peak soon, it should be possible to preserve the ice sheets until they are again viable. If they keep rising, the aim will be to manage the collapse of the ice sheets to smooth the rate of sea-level rise and ease adaptation.

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31 Responses to “Could Geo-Engineering Stave off Climate Disaster?”

  1. Sir Charles Says:

    … Means just wasting more energy and money for experiments. Geo-engineering looks to me like preparing a basement to be emptied with buckets you have to design yet instead of building a dyke against the imminent flood. Mitigation and within fast and massive ramp up of renewable energy supply, that’s what I call sustainable solutions which do work 100%, that’s where money should be directed to.

  2. dumboldguy Says:

    Sell your Solar Roadway stock, folks—-this is a far better opportunity to waste billions of dollars on a pie-in-the-sky bit of foolishness. Drill through a mile of ice to “pump water”? Build 300 meter high seabed mountains to “pin” ice sheets in place? Build 100 meter tall and 2 mile long walls to “hold back” warm water?

    Lord love a duck, but we have truly gone through the looking glass with Alice!

    https://goo.gl/images/bLCYmX

    • grindupbaker Says:

      That isn’t so obvious to me. Quite likely rubbish but not certain because it depends on the glacier length-to-width ratio. Analogy pinprick hole in a spacecraft and air escaping. If the quantity is very large compared with the escape opening then it might not be too outrageous in terms of cost effectiveness.

      • dumboldguy Says:

        Weak analogy, scale-wise. You can perhaps stop a pinprick leak in a spacecraft with a wad of chewing gum with a domino over it (or mahjong piece if you’re a Chinese astronaut).

        Look again at the immensity of these suggestions and the engineering difficulties and unknowns they present. Alice lives!

    • redskylite Says:

      This kind of reminds me of an interesting dialogue you had many moons ago with E-P’s idea of spraying white paint across the Arctic ice sheet to restore the albedo and reflect incoming radiation. Who would finance such a monster project on the Antarctic ?, who among the fragile treaty would take responsibility? I can only believe the author’s intent was to draw attention to the urgency of getting the carbon balance back in a natural pre-industrial harmony. Or they simply had too much time on their hands.

      And what about the other glaciers . . .

      Sea level fears as more of giant Antarctic glacier floating than thought.

      More of a giant France-sized glacier in Antarctica is floating on the ocean than previously thought, scientists said Tuesday, raising fears it could melt faster as the climate warms and have a dramatic impact on rising sea-levels.

      The Totten Glacier is one of the fastest-flowing and largest glaciers in Antarctica with scientists keen to keep a close eye on how it melts given the enormous amount of water it could potentially unleash.

      https://www.afp.com/en/news/2265/sea-level-fears-more-giant-antarctic-glacier-floating-thought-doc-12u3ti2

      • dumboldguy Says:

        We have graduated from painting the ice white to covering it with reflective crystals.

        https://www.revealnews.org/article/what-on-earth-why-climate-change-skeptics-are-backing-geoengineering/?

        Geoengineering will be the next “great experiment” we will conduct on the only planet we have—-it will occur when everyone panics because we waited too long to deal with AGW and the SHTF.

        • Sir Charles Says:

          It’s part of a journey that began in 2006, after Leslie Field watched the climate change documentary “An Inconvenient Truth” and felt like she’d been “hit by a big fat truck.” Now, she hopes to gather global support to cover more than 19,000 square miles of sea ice – an area about the size of Costa Rica – with a thin coating of tiny floating silica spheres, which she claims will help reduce the world’s rising temperatures.

          The cost estimate? $1 billion a year.

          “I keep thinking, ‘If not me, who?’ ” Field, a former researcher at Chevron Corp. and HP Labs, said as she led a reporter through a wholesale flower shop that shares access with her office.

          In the emerging field of geoengineering, which envisions large-scale efforts to fight climate change by directly manipulating the natural environment, Field’s privately funded Ice911 project is a small player. Under the Trump administration, these eclectic, messianic and mostly untested projects have been gaining unprecedented momentum.

          Plastic is made from oil.

          • dumboldguy Says:

            Plastic is made from oil? DUH! Your point?

            http://www.ice911.org/

            This group is far more qualified than the Solar Roadway folks and their website is slick, but this is just another scam—-get some government $$$$ and crowd-source, and live high on the hog. There are too many of them though, and not enough teats on the hog, so they likely won’t do as well as the SR crew.

            Unfortunately, the very first line on the home page of 1ce911 is this—on further reading, it is obvious that they will not be “restoring” any ice but merely attempting to slow the rate of arctic warming.

            “Ice911 is acting to lower global temperatures by restoring ice in the Arctic”.

            PS Chucky, Why don’t you instead spend the time showing us that you have done your homework and can explain the relationships between ice SHEETS, ice SHELVES, ice BERGS, CALVING, and GLACIERS?

          • dumboldguy Says:

            PS One of Field’s big admirers is Armond Cohen

            “Armond Cohen is Co-Founder and Executive Director of the Clean Air Task Force (CATF), a non-profit organization dedicated to reducing atmospheric pollution through research, advocacy and private sector collaboration. Among other efforts, CATF is actively promoting the demonstration and adoption of low carbon coal technology in the US, China and India”.

            See those last words? Nuf’ said.

          • Sir Charles Says:

            So, it’s coming all together. Plastic is made from oil, and coal is made from coal…

          • dumboldguy Says:

            Have another Guinness and it will become perfectly clear.

    • leslie graham Says:

      Early days of course but solar roads are a no-brainer.

      http://www.ecotechtube.com/flashes/detail/761/new-1-km-solar-road-opens-in-jinan-china

      Solar roadways USA just signed with a manufacturing partner too.

      http://www.matr.net/article-81633.html

      Just saying.

      Wireless charging of autonomous EV’s is also a no brainer.
      Just a decade away – time to buy in.

      • dumboldguy Says:

        Anyone who thinks solar roads are a “no brainer” needs to look at the costs and technical failures of the concept.

        “Zhang said the road cost about 3,000 yuan, or $458, per square meter, and as that is more than regular streets, it may take some time for the project to expand”.

        Yes, that is at least FOUR times the cost per m2 of conventional roads, and far more expensive than mounting the solar panels on poles in the conventional way along the road right or way. As I said, anyone who wants to pour money down a rat hole can find few ways better than to invest in solar roadways.

        As for “signing with a manufacturing partner”, don’t hold your breath waiting for Solar Roadway panels to come rolling out the door in any numbers. The company was founded in 2006 (11 years ago) and still hasn’t produced anything but “demonstration projects”, all of which are designed to part more fools from their money and provide a comfortable living for the “geniuses” behind the curtain. To wit:

        2009—$100,000 Small Business Innovation Research (SBIR) grant from the United States Department of Transportation (USDOT)
        2011—$750,000 SBIR grant from the DOT
        2014—a crowdfunding drive at Indiegogo raised 2.2 million dollars
        2015—USDOT awarded Solar Roadways a Phase IIB SBIR contract to further their research
        2016—they were given an additional $750,000.00

        That’s a total of at least 3.8 million dollars since the start, or ~$350,000 per year. Nice work if you can get it.

        The first public installation in Sandpoint, Idaho opened to the public on September 30, 2016 (10 years in). A pilot install for walkways only, it consists of 30 Solar Roadways SR3 panels covering an area of roughly 150 square feet (14 m2). The cost of this installation was roughly $60,000 (that’s 4+ THOUSAND dollars per m2).

        The majority of the money came from a grant from the Idaho Department of Commerce ($47,134), and a $10,000 grant from the Sandpoint Urban Renewal Agency. The 30 tiles in Sandpoint aren’t yet generating power—however, the City of Sandpoint’s Proposed 2016-2017 budget includes $500,000 for future Solar Roadways projects. They’re gamblers too, and are hoping to bring jobs to the ass end of Idaho—-wonder what the voters will think?

        And wireless charging of EV’s is no big deal—although it too is taking a long time to take off for the simple stationary type, and the “charge while driving” idea is Solar Roadway’s idiot cousin.

        Why are you so eager to buy into wishful thinking and bright-sidedness?

  3. Sir Charles Says:

    The coveted Golden Crocoduck…

  4. Keith McClary Says:

    I have a better idea. According to my calculations, if we build a giant wall all around Antarctica, containing all ice flow and meltwater (i.e., trapping all precipitation), it would contribute a sea level decline of 6mm/year.

    And we can make the penguins pay for it!

    • grindupbaker Says:

      That proposed project is old news. Some geezer (you?) suggested Antarctica wall on ootoobs 5 years ago and I suggested the fairground scam where tourists throw hoops over the wall and get a giant teddy bear if it lands on some peak. Mind you, that’s when walls were exciting commercial enterprises and not something you get a bunch of foreigners to hoof the bill for. Walls have changed now.

  5. grindupbaker Says:

    I don’t see how “these two glaciers might disgorge ice ten times faster than current rates, contributing 4 centimetres a year to global sea-level rise” is possible unless the +3.4 mm/year current rate I saw plotted is now old hat. If all glaciers on Earth disgorge ice ten times faster then that would be ~+2.0 centimetres a year to global sea-level rise according to my advanced mathematics & assuming thermosteric SLR at +1.6 mm/year.

  6. redskylite Says:

    Just a weird thought that keeps occurring to me, but the thought of puny mankind trying to hold back the inevitable might of nature, and some of the petty thoughts and banter we are fighting the problem with, are we sure that we are not being affected?, just like the dear squids.

    Hunting squid slowed by rising carbon levels

    Scientists have found that high carbon dioxide levels cause squid to bungle attacks on their prey.

    https://www.coralcoe.org.au/media-releases/hunting-squid-slowed-by-rising-carbon-levels

  7. redskylite Says:

    I have to agree with the Earth Institute, Columbia University. We do need laws and quickly, before more “well-intention-ed” damage is done. Trouble is getting global acceptance.

    Humans have been accidentally altering the planet’s climate for thousands of years. Soon, it may be possible alter it intentionally.

    The deliberate, large-scale manipulation of climate is called geoengineering. The term encompasses a variety of proposals, from pulling carbon dioxide out of the atmosphere to reflecting sunlight back into space in an attempt to slow the earth’s warming. Global geoengineering tactics haven’t yet been deployed, but as climate change starts to spin out of control, support for some forms of geoengineering seems to be growing.

    However, there’s a lot that can go wrong when it comes to modifying the complex global climate system, and the world is not prepared for the problems that might result.

    http://blogs.ei.columbia.edu/2018/03/20/geoengineering-climate-law-book/

  8. redskylite Says:

    Save the money and spend on cutting GHGs instead as suggested by UCAR .

    The scientists found that reducing greenhouse gas emissions would not significantly restrain sea level rise for the next two decades. The reason, in part, has to do with the inertia of the climate system (once heat enters the oceans, it is retained for a period of time). In addition, winds and currents are naturally variable from year to year, pushing ocean water in different directions and making it hard to discern the full impact of planet-scale warming over the span of a decade or two.

    But the scientists found that later in the century, from 2061 to 2080, reduced emissions would have a significant impact across almost the entire world.

    https://www2.ucar.edu/atmosnews/news/131966/cutting-greenhouse-gas-emissions-would-help-spare-cities-worldwide-rising-seas


  9. […] The rate of ice loss will still be governed to a large degree by how fast humans add greenhouse gases to the atmosphere – in other words, losing West Antarctica in say, 200 years, is a quite different from losing it in 7, or 900 years.  Time to adapt, and perhaps deploy geoengineering fixes. […]


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