The only way that "frequent" volcanic eruptions could cause a warming effect is if enough CO2 were emitted to change the radiative balance of the atmosphere. As this is the Anthropocene and not the Cretaceous, I think that unlikely. I still fail to see the risk to or threat from Canadian Newfoundland as it has no glaciers and hasn't had any for 8,000 years. The use of stratospheric aerosols would have no impact on volcanic eruptions or earthquakes since it wouldn't increase the amount of ice significantly. You can't make up for hundreds of years of melting in a few.
I am interested in Song's "experiments" supposedly demonstrating the potential of glacial earthquakes to cause tsunamis. Are these the results of models or are there field measurements to back them? Once again, my call for a comprehensive risk assessment of the structural stability of the ice sheets. Of course, since we don't seem to give a rip about the stability of bridges until there is a crack in a major part big enough to see from the highway (Oakland Bay Bridge) why am I not surprised no such study has been undertaken? And if we did find that a large crack was developing in the Greenland or Antarctic Ice Sheets, what would we do about it? This comes back to MacCracken's argument about waiting until it's too late to take action, my analogy of the patient with diabetes (wait until the heart attack for intervention) and society's requirement for a crisis before doing anything. You can't put the ice back on the ice sheet via enhanced precipitation and you sure as hell can't do it once it's floating in the water and NYC and London are destroyed. This just in. Man-made CO2 emissions will not be stabilized in the next five years. ----- Original Message ----- From: "Andrew Lockley" <[email protected]> To: <[email protected]> Cc: "Geoengineering" <[email protected]>; "Bill McGuire" <[email protected]> Sent: Thursday, September 17, 2009 9:02 PM Subject: [geo] Re: Colloquium report: hazards from global warming > > This raises interesting points about the limits of SRM geoengineering. > Perhaps the experts on the list could explain why frequent volcanic > eruptions cause a warming effect? Can we be sure that H2S > geoengineering techniques we propose cannot result in this 'blowback'? > > A > > 2009/9/17 John Nissen <[email protected]>: >> >> This is a press report on the first day of the Hazards Colloquium, >> organised >> by Bill McGuire, at UCL, London. >> >> http://planetark.org/wen/54708 >> >> Global Warming May Bring Tsunami And Quakes: Scientists >> >> Date: 17-Sep-09 >> Country: UK >> Author: Richard Meares >> >> LONDON - Quakes, volcanic eruptions, giant landslides and tsunamis may >> become more frequent as global warming changes the earth's crust, >> scientists >> said on Wednesday. >> >> Climate-linked geological changes may also trigger "methane burps," the >> release of a potent greenhouse gas, currently stored in solid form under >> melting permafrost and the seabed, in quantities greater than all the >> carbon >> dioxide (CO2) in our air today. >> >> "Climate change doesn't just affect the atmosphere and the oceans but the >> earth's crust as well. The whole earth is an interactive system," >> Professor >> Bill McGuire of University College London told Reuters, at the first >> major >> conference of scientists researching the changing climate's effects on >> geological hazards. >> >> "In the political community people are almost completely unaware of any >> geological aspects to climate change." >> >> The vulcanologists, seismologists, glaciologists, climatologists and >> landslide experts at the meeting have looked to the past to try to >> predict >> future changes, particularly to climate upheaval at the end of the last >> ice >> age, some 12,000 years ago. >> >> "When the ice is lost, the earth's crust bounces back up again and that >> triggers earthquakes, which trigger submarine landslides, which cause >> tsunamis," said McGuire, who organized the three-day conference. >> >> David Pyle of Oxford University said small changes in the mass of the >> earth's surface seems to affect volcanic activity in general, not just in >> places where ice receded after a cold spell. Weather patterns also seem >> to >> affect volcanic activity - not just the other way round, he told the >> conference. >> >> LONDON'S ASIAN SUNSET >> >> Behind him was a slide of a dazzlingly bright orange painting, "London >> sunset after Krakatau, 1883" - referring to a huge Asian volcanic >> eruption >> whose effects were seen and felt around the world. >> >> Volcanoes can spew vast amounts of ash, sulphur, carbon dioxide and water >> into the upper atmosphere, reflecting sunlight and sometimes cooling the >> earth for a couple of years. But too many eruptions, too close together, >> may >> have the opposite effect and quicken global warming, said U.S. >> vulcanologist >> Peter Ward. >> >> "Prior to man, the most abrupt climate change was initiated by volcanoes, >> but now man has taken over. Understanding why and how volcanoes did it >> will >> help man figure out what to do," he said. >> >> Speakers were careful to point out that many findings still amounted only >> to >> hypotheses, but said evidence appeared to be mounting that the world >> could >> be in for shocks on a vast scale. >> >> Tony Song of NASA's Jet Propulsion Laboratory in California warned of the >> vast power of recently discovered "glacial earthquakes" -- in which >> glacial >> ice mass crashes downwards like an enormous landslide. >> >> In the West Antarctic, ice piled more than one mile above sea level is >> being >> undermined in places by water seeping in underneath. >> >> "Our experiments show that glacial earthquakes can generate far more >> powerful tsunamis than undersea earthquakes with similar magnitude," said >> Song. >> >> "Several high-latitude regions, such as Chile, New Zealand and Canadian >> Newfoundland are particularly at risk." >> >> He said ice sheets appeared to be disintegrating much more rapidly than >> thought and said glacial earthquake tsunamis were "low-probability but >> high-risk." >> >> McGuire said the possible geological hazards were alarming enough, but >> just >> one small part of a scary picture if man-made CO2 emissions were not >> stabilized within around the next five years. >> >> "Added to all the rest of the mayhem and chaos, these things would just >> be >> the icing on the cake," he said. "Things would be so bad that the odd >> tsunami or eruption won't make much difference." >> >> > >> > > > --~--~---------~--~----~------------~-------~--~----~ You received this message because you are subscribed to the Google Groups "geoengineering" group. To post to this group, send email to [email protected] To unsubscribe from this group, send email to [email protected] For more options, visit this group at http://groups.google.com/group/geoengineering?hl=en -~----------~----~----~----~------~----~------~--~---
