LESSONS ON ICE DYNAMICS FOR PROSPECTIVE GEOENGINEERS Dear Peter, As per your suggestion to Geoengineering group, It is not possible to get ice bergs to sit on the bottom of the sea in front of an active ice fjord by pumping sea water to build ice height to make them grounded and thus anchored at the sea floor. In the mouth of every ice fjord there is huge shallow that forms a submerged threshold or 'sill' in solid rock where the former valley glacier was fanning out as it debouched from the constraining walls of the valley, thereby reducing its erosive ability and where melting occurred near to its terminal zone. Some of the thresholds have a superficial draping of terminal moraine. When the ice bergs pass the threshold, it is here the heavy soil and rock laden bottom of ice (that will never afloat) separates and falls, at the latest. When this ice from fjord reaches the sea its bottom basically falls off or disintegrates, and in time these may have built banks of rock and soil at or near the sea entrance of ice fjords. It is this bank of rock and its variously deposited material which then breaks up the ice that is had been pushed down from the uphill. While the ice in the over-deepened valleys of ice fjord are of great height (bottom of ice heft in excess of 1,100 metres below sea level), the terminal strandflat barrier will break up and slice the tall glacier into much smaller ice bergs that become freely floating rather than pressed against ice fjord bottom. When the density of ice is lower than that of water the ice surfaces; when it is greater, the ice stays under water and breaks up further until the heavy rock incursions are ejected and the fractured ice reaches its buoyancy or melts away. When the ice bergs have passed the terminal strandflat barrier of the ice fjord, the bottom of the sea floor never reaches the free floating ice again. The large, naturally held congestion in front of glacier is called ice shelves. The geoengineering proposals made have suggested of maintaining the free floating ice bergs together as an artificial ice shelve, by suspension cabling and other means, to create an artificial ice shelve to slow down the flow of ice behind. However, in case of storms, such an assembly would easily scatter as the tug boats and cabling capacity could quite easily be overloaded. The costs of maintaining a fleet of tug boats and the health and safety related practical risks of managing large unstable ice bergs are important as ice impacts of turning ice berg can easily destroy even large and strengthened vessels. Therefore, the suggestion loading more ice by pumping sea water to ice bergs does not make any sense as the break-up force behind strandflat is greater than the friction, if it is not, then the ice flow stops and the ice melts away peacefully in situ and its is no longer ice berg forming fjord, hence the descriptive name "ice fjord" versus an ordinary "fjord". When it comes to the super-icebergs that have grounded to the deep sea floor on the Lomonosov Ridge or also far off the South-East Greenland coast, these mega-icebergs that have grounded deep sea floor, in my view, are evidence of the past ice sheet land containment failures that allowed the large fragments of destabilised ice dome to fall off land (as per the UN complainant nations). The ice fjords are a natural part of a healthy and stable ice sheet, a valve system, that allows the excess ice to excape where the ice sheet land containment barrier's edge around the ice sheet is lower than elsewhere. A natural feedback occurs as ice starts flow, the flow of ice carving and enlarging the original V valleys to larger and less constrained U valleys due to throughput of ice. In time, the passage of ice on these points have become easier than originally, and they become the established routes for excess ice to discharge and leave the glacier. The IPCC official forecast of 18 cm per century sea level rise from the melting ice (and expanding sea water as it warms) has been based on assumption that ice melts peacefully in situ and the run off water then falls into sea basins and raises the water-table in gradual fashion. The Western Nations view is that the Foxe-Laurentide ice sheet melted away from Last Glacial Maximum (LGM) to Youngest Dryas for 15 kyr. This case history of the disappearance of the Foxe-Laurentide has been incorporated to IPCC's paradigm of slowly rising sea level as the ice sheet largely was believed to be resting and melting away peacefully in situ. This serene view of impact of global warming has been challenged in the United Nations General Assembly by the First Nations' of the North America who claim under the auspices of World Indigenous Nations Convention that the western paradigm is failing and be a fake case history what happened to the huge ice dome that once rested over the Hudson Bay area. There are clear evidence recently emerged that the IPCC's ice melting paradigm and 18 cm sea level rise is utterly wrong. Back in 2007 when I was the press-spokesman for "the Arctic - Mirror of Life" symposium convened by HE Kofi Annan (UN Secretary-General) and HE Jose Manuel Barroso (President of European Commission) it was becoming to attention that there was also an overall speeding-up of the glaciers in the ice fjords. The 'slip-slide' of the glaciers was discovered to increase the discharge rates of the ice bergs: a flow of melt water under the ice fills up cavities and creates a separating layers of water where the contact between the ice and the bed rock are reduced in the glaciers feeding into the ice fjord. As there is downward ground inclination, the gravity then pulls the ice forward more forcibly as the slope under the ice has now less friction. The sea leve rise have been re-estimated since the last IPCC report and the maximum speed estimated from Greenland's slip-sliding glaciers gives the increased overall sea rise figure of upto 2 metres, towards the end of the century if the escalation of ice bergs slip-sliding continues to spread to all ice fjords of Greenland. However, as the ice does have very low friction and UK Meteorological Office's latest projections suggest an overall annual mean temperature warming of the entire Arctic to be +15.2C, the Arctic Basin's temperature rise to be +16.0C or more, and in some places like in the vicinity of the North Pole the annual mean temperature rise to be as much as +20.0C, the melting of Greenland's Ice Sheet should become extremely intensive. This then, throws back to the issue raised by the First Nations of the North America to the United Nations General Assembly: according their old recollections, the warmed and wet ice sheet started to float on its own melt waters, it lost its footing on elevated grounds behind the Baffin Island, and cascaded very rapidly in a large ice-avalanche-event excavating much of the Hudson Straight in the process. If so, we should expect similar event in Greenland in Melville Bay section due to the anthropogenic global warming just like when ice age ended. It is these large ice dome fragments falling from the land that had the sufficient lateral spread, and therefore ice berg heft, to be able to ground in the deep sea floor of the ocean in places like the Lomonosov Ridge and also the deep water ice berg groundings in nearly kilometre deep waters far off the South West Greenland. (There are probably more of these to be found if people just look for them from right places.) The chief problem I can see of seeing the ultra-deep ice bergs (a kilometre or so, grounding depth) that the ice fjords do not allow tall vertical ice bergs structures to form and also stay afloat upright to reach and carve up the deep ocean beds like the Lomonosov Ridge, or the South West Greenland sites. I may be wrong, but then, I think someone has to pinpoint fjords that did not have not the terminal strandflat barrier that slices the glaciers (much like egg slicer) into much smaller ice that then break up and can float over the strandflat to become free floating ice bergs on the oceans. Where are the strandflat-free fjords that produced these thousand metres and over deep-swimming bergs? As Greenland Ice Sheet will start to float on its own meltwaters in the post-sea ice Arctic Ocean, and the ice-free North Pole, and if the UK Meteorological Office projections of the huge temperature increases referred above materialise, the increasingly melt water lubricated and floating ice sheet will loose its connectivity to the base rocks beneath. (UK Meteorological Office article and web-link is enclosed below.) At the core of the World Indigenous Nations Summit's complaint to the United Nations is the emergence (and re-awakening) of a new type of geological thrust, "ice sheet thrust" where a fault occurs between the overlying warmed and wet ice sheet and its underlying bedrocks. The ice on the elevated grounds leans its weight increasingly against ice-constraining obstacles until the freed weight of the ice exceeds the barrier's ice holding capacity. This tipping point is very much similar to all the other geological faults where two stressed surfaces detach suddenly from each other producing sudden earthquake like slips. The sideway (horizontal) passage of the two moving surfaces is called strike-slip fault, but in case of ice sheet fault the passage is an overtaking (vertical) passage of the two moving surfaces that points its force toward the lowest constraining barrier elevation. If the ice holding capacity is exceeded, a land subsidence towards sea develops then rapidly. If the Foxe-Laurentide Ice Dome detached and fell off the Hudson Bay, like the indigenous North American's seem to insist to the UN, the rapid erosion forces would have materialised when the "ice sheet thrust" caused a fault to occur in the mooring of the ice dome over the basin now known as the Hudson Bay. The first of these rapid erosion forces occurring under the moving ice dome would have been the cavitation when the water under the moving ice sheet started to move very fast, creating tiny vacuum bubbles that formed along the rock surfaces which then explode inwardly in a rapidly moving water. The bubbles explode inwardly and pound the rock with a great foce reducing it quickly to powder. The cavitation process is soon complemented by the plucking as the impacting ice, water and rock debris starts to rip up loose blocks of bedrock that collide and create further shower of fast moving debris. In the abrasive action ice is also converting to water increasing rapidly the volume of available water in the ice - bed rock interface. In places, there forms underwater tornado-like currents called the kolk, which (just like tornado in the air) can lift and remove large chunks of the underlying material. Tubulent currents like kolking may also be the cause of giant's cauldrons and potholes (although the water pouring in moulins over extended periods of time can also cause these formations even in hard granitic rocks). Whatever the case, I can see chances of Greenland ice sheet loosing its footing in the post sea ice Arctic and the claim of the strong coupling between the Arctic marine and terrestrial ice losses be a near future reality in a much shorter time frames than previously thought, and certainly IPCC's 18 cm sea level rise prediction to year 2100 is too fanciful. Like in the climate change there is Type 1 (gradual climate change) and Type 2 (abrupt climate change), there are gradual erosion by weathering of rocks tidals forces, frost etc., but also a rapid erosion with the action of far greater impact, major high-enery events occurring under destabilised, warmed and wet ice sheet which loses its footing due to excessive melt water accummulation between ice and bed rocks. If you have any queries, our last discussions in New York and at the United Nation did not produce as much as we had hoped for. Though, we are keenly following invitation by the government of Egypt who seem to have given ear to our ideas about the risk of sudden sea level jump emerging from Greenland and its potential damage to the economy of Egypt if Nile Delta agricultural area gets flooded, plus the potential of emergency agriculture if the Last Dryas cooling occurs much alike in the Day After Tomorrow film as the North Atlantic Ocean becomes loaded with tens to hundreds of millions ice bergs from the collapsed Greenland ice dome and upper Egypt's agricultural zone suddenly expanded (until the sea water mixing pushes the newly formed fresh water layer to the sea floor after it mixes few years with saline water and cold sinks to the sea floor and the Atlantic Ocean re-stratifies and warms up again). In the Southern Atlantic the sudden sea level jump causes a teleconnected ice berg event as the higher sea level bends and may break off the Ronne and Ross Ice Shelves, speeding up greatly the WAIS glacier run off, in a synchroneous fashion, in the subsequent years. Should we put a cable around these? Simply, not possible.
Kind regards, With kind regards, Veli Albert Kallio, FRGS HH Plenipotentiary Scientific Ambassador, Global Environmental Parliamentary Group United Nations' General Assembly complaint UNGA 101292 complaint handler for the the First Nations' of the North America (under auspices of the World Indigenous Nations' Summit and its closing plenary request to the Western Group of Nations) http://www.metoffice.gov.uk/climatechange/news/latest/four-degrees.html Four degrees and beyond 28 September 2009 If greenhouse gas emissions continue to rise unchecked, it is likely that global warming will exceed four degrees by the end of the century, research by Met Office scientists has revealed. Dr Betts said: “Four degrees of warming, averaged over the globe, translates into even greater warming in many regions, along with major changes in rainfall. If greenhouse gas emissions are not cut soon, we could see major climate changes within our own lifetimes.” High-end temperature change Fig 1. Comparison of surface temperature projections from the high-end emissions scenario, without carbon cycle feedbacks. Temperature increases between 1961-1990 and 2090-2099, averaged over all high-end members. In some areas warming could be significantly higher (10 degrees or more). The Arctic could warm by up to 15.2 °C for a high-emissions scenario, enhanced by melting of snow and ice causing more of the Sun’s radiation to be absorbed. From: [email protected] To: [email protected]; [email protected] CC: [email protected]; [email protected]; [email protected]; [email protected] Subject: [geo] Re: Robeson Channel Suitable for Suspension Cabling to Block Prevent Southward Ice Movement Date: Sun, 4 Oct 2009 17:36:36 +1300 Just a thought Once you've got the ice bergs to stop near an entrance to this or some other channel then maybe spend all winter spraying salt water onto it that freezes and gradually weighs the bergs down till they sit on the bottom. Then spray some more on so it sits on the bottom good and hard. And then some more to make sure there's enough left at the end of the summer. How many tons of salt water spray? How much fuel to shift it?? How much CO2 emitted??? More harm than good ???? Anyway, maybe the channel will block up enough all the way back to where the glacier is falling into the water and stop it from sliding off Greenland (or Antacrtica) and all will be well ?? Or do some people live up this channel? Do they want to get in and out in summer time?? Maybe build a road. Or shift them like the Tuvalese. Politics again. Hmmm. Peter ----- Original Message ----- From: John Nissen To: [email protected] Cc: [email protected] ; Geoengineering ; Risto Isomaki ; Esko Pettay Sent: Friday, October 02, 2009 10:42 PM Subject: [geo] Re: Robeson Channel Suitable for Suspension Cabling to Block Prevent Southward Ice Movement Hi all, Some time ago, Albert and I discussed cables and barriers at length - and at a length to cross straits. You really want a valve, that will let ice flow in one direction (North) but not the other (South). It's quite difficult to do that with a cable. My thoughts are that a floating barrier might be best. It can be rounded and point into the ice, so that ice pressure becomes a compression of the barrier. Basically what you want is to create an ice jam of ice flows (or icebergs) on one side of the barrier which would then take most of the pressure as the ice builds up. The barrier could be made across a fjord or across straits. The barrier would be made of sections, so it could come apart to let ice flow in the opposite direction (possibly in two sections, like canal lock gates). The barrier could possibly be made out of pykrete [1], which has excellent compressional strength (over twice as strong as normal ice) and good tensile strength as well (much better than concrete) to give it rigidity, while having a density less than water so it floats (just). One major problem with such a barrier (across straits) could be when the wind is from the North, while the sea current is from the South, keeping the barrier open. BTW, I've seen recent research suggesting that there is a stable weather condition which can sit over the North Pole, with winds which tend to disperse the ice. This condition is considered to have been instrumental in the unprecedented sea ice retreat in 2007. Perhaps one of you can find a reference, please. Cheers from Chiswick, John [1] http://en.wikipedia.org/wiki/Pykrete Mike MacCracken wrote: What about doing this across Jakobshaven and other fjords that allow ice streams to flow rapidly? Mike On 10/1/09 9:25 AM, "Veli Albert Kallio" <[email protected]> wrote: Dear All, Please find enclosed a brief satellite animation on the Robeson Channel from this summer which suggest that use of bridge-style suspension cabling could hold ice in place and prevent it moving into the warm waters further along the channel between Ellesmere Island and Greenland. The link attached below which shows the summertime ice movements. The shortest suspension cables would be Ellesmere - Hans Island - Greenland each stretch about 10 kilometres in length. (The concept is to create ice congestion behind barrier that is self-locking jam of pack ice behind cable that remains longer in the cold waters.) On the negative side, the ice amount south of any successful cable barriers will decrease. The impact of cables for boats, whales and perhaps other large fish and wild life would also have to be addressed. After melting, the barrier cable is lowered to the seafloor when ice is on northward move or there is a lack of ice, the barrier is raised up to surface whenever there is ice flow moving southward. It is also raised up to surface for the winter freeze. In Nunavut, the suspension cabling could help to keep the North West Passage clear of thick sea ice floes that damage ships while preserving ice on the north side of the channel. This might help justify such a system at least in Nunavut. The profile of the Swalbard Islands and Franz Joseph Land could also be enlarged by blocking the straights by cables. This would increase the ice congestion behind these archipelagoes and decrease some sea ice escape from the high Arctic Basin. I have not considered blocking of the Fram Staight due to its width, but materially the largest amount of sea ice loss through escape will occur there. The barriers can slow down ice movement and loss to the south due to decreases in ice movements but if ice melts away due to warm weather behind barrier, these measures become all but useless. Kind regards, Albert From: [email protected] To: [email protected] Subject: Greenpeace dokumentoi pohjoisen pallonpuoliskon jäätiköiden sulamista Date: Thu, 1 Oct 2009 14:18:14 +0300 http://www.greenpeace.org/finland/fi/mediakeskus/lehdistotiedotteet/greenpeace-dokumentoi-pohjoise <http://www.greenpeace.org/finland/fi/mediakeskus/lehdistotiedotteet/greenpeace-dokumentoi-pohjoise> View your Twitter and Flickr updates from one place - Learn more! <http://clk.atdmt.com/UKM/go/137984870/direct/01/> No virus found in this incoming message. 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