RE: [geo] Coupled Model Intercomparison Project 5 (CMIP5) simulations of climate following volcanic eruptions
Atmosmare is working on idea of ships being allowed to use SO2 containing fuels. However, it bears to be remembered that SO2 turns into sulphuric acid. We had acidification problem in 1970s and in Kola Peninsula near Murmansk and Nickel the heavy industries sulphate emissions have turned Arctic landscapes into acidic lunarscape. The power stations are no capped and situation gradually normalising, i.e. lichen what the raindeers eat started to disappear. Norilsk region in the Taimyr Peninsula also faces similar problems and has installed filters. This may explain some regional warming in the Arctic. I would say that the harmful effects of acidification start occurring within 5 years if SO2 was removed with the lakes becoming first dead. This in 15-20 years time followed by the forests dying out like in Germany. It is possible to throw out SO2 for a while but it is a bit like putting too much salt on an egg, it won't work for long. Like too much CO2 is too much, so it is with SO2 which is even faster cul-de-sac. But I agree with the high stratospheric life times which make the substance more effective. I think the airplanes are just too complicated at this point of time, as an intermediate solution mountain top piping would be easier to build and also dismantle. The facilities could also be controlled so that the gas would not be released into rainy weathers and when the winds blow towards lands. I think intelligent solutions would prolong the life of sulphur aerosol cooling and reduce the quantities required. Jan Mayen's Beerenberg, Greenland's Gunnbjorn, some Norwegian mountains would be ideal as Gunnbjorn at 3800 metres is above many clouds (Arctic air mass is thinner than the tropics). In Africa possibly Mt. Kilimanjaro and Mt. Meru and Mt. Kenya could be used as these would take to 7 km high and also intelligently controlled whenever there is no rain and winds would be towars the oceans to create reflection and aerosols over oceans. Volcanoes of the Macarene Islands (Reunion, Mauritius) could also be used to spread widely as well as the South Atlantic islands like Acension, the Inaccessibility Island, etc. which have high mountains above the ocean. The factories traditionally put their gas out whatever the weather, the rains might bring the dirt down few miles from the factory within 15 minutes. Geoengineering programmes based on SO2 must clearly differentiate from these practises to be acceptable. (I try to contribute nowadays less due to a simple fact that we have more shinier brains on the group nowadays, to prevent overloading with messages. There is an allergy among the decision-makers against geoengineering as some of the ruling elites are not even yet accepting man made emissions of CO2 as greenhouse gases and do not believe in the theories that one could add or deduct energy from atmospheric budget. This is of course wrong, but makes it particularly hard to sell geoengineering to business-courting politicians around the world.) Kind regards, AlbertDate: Fri, 14 Sep 2012 17:00:30 -0430 Subject: Re: [geo] Coupled Model Intercomparison Project 5 (CMIP5) simulations of climate following volcanic eruptions From: mmacc...@comcast.net To: Geoengineering@googlegroups.com Re: [geo] Coupled Model Intercomparison Project 5 (CMIP5) simulations of climate following volcanic eruptions Hi John—Regarding your query about changing power plant emissions, think back to the situation in the mid-20th century when all the black soot and ash was also coming out of power plants. Modern coal-fired power plants are tuned so as to not make much soot (it is wasted energy) and filter out most of the rest. For SO2, many are already taking much of that out as well. Your question might better be could one have power plants not remove the SO2. Doable, but would likely have significant health and acid precipitation consequences. It would make much more sense, were one to want to augment the sulfate amount in the free troposphere to enhance the cooling effect to take the S that has been and is being scrubbed out of power plants and then set up release locations in the remote, low latitude, mid Pacific and Indian oceans, oxidize the S, loft it to above the boundary layer to increase its lifetime, and so generally increase the tropospheric sulfate loading while also benefitting from some amount of cloud brightening effect—doing so over the low albedo ocean areas where there are very few people and lofting above the boundary layer would be important. So, one would benefit from large area, sharp albedo contrast, sun well up in the sky, etc., so augmentation of loading might be low enough to avoid serious consequences when a fraction of the emitted sulfate eventually got carried to populated areas and areas sensitive to acid deposition (acid deposition is especially a problem when get buildup on snow over winter and then rapid melt—and would avoid that). Now, some
Re: [geo] Coupled Model Intercomparison Project 5 (CMIP5) simulations of climate following volcanic eruptions
Hi Mike, Could there be a method of selective filtering of coal-fired power stations, such that the cooling aerosol (or SO2 precursor) is allowed into the troposphere while the black carbon is removed? Cheers, John --- On Tue, Sep 11, 2012 at 7:15 PM, Mike MacCracken mmacc...@comcast.netwrote: Hi Stephen—I would think that Chinese sulfate (like tropospheric sulfate from virtually anywhere) would contribute to cloud and free air brightening, so a cooling influence (especially when that sulfate is above the dark Pacific Ocean). Now, in that coal plants put out more than pure SO2, there might well be some components (such as black carbon) that would exert a strong warming influence, especially if they are carried far enough to deposit on snow and/or ice during the sunny half of the year in the Arctic. For net effect, there is need for much more analysis than I have seen. On limiting heat reaching the Arctic Ocean, there have been suggestions to even build a dam across the Bering Strait—as long ago as the mid-20th century (though I think then it was with the intent to warm the Arctic). My guess on the kelp idea is that the sunny part of the year is not long enough for that approach to be all that practical (not only is the sunny part of the year short, but the sun angle is often not helpful). And sea ice is typically only a few meters thickness, so no where near 30 m. Mike On 9/11/12 12:48 PM, Stephen Salter s.sal...@ed.ac.uk wrote: Mike Do you think that the higher levels of SO2 from Chinese coal burning could account for some of the increase in Arctic temperatures? Another thought for your list might be to increase the drag of water flowing in through the Bering Strait. In summer kelp grows at an amazing rate but not below about 30 metre water depth because of the shortage of light. The net flow is 800,000 m3 a second and it will be warmer than polar water so a small velocity reduction makes a big difference. What if we put strong ropes moored at 30 metres to give them kelp a foot hold? If kelp gets scraped off by floating ice it will can grow again. Does ice reach down to 30 metres? Stephen On 11/09/2012 18:05, Mike MacCracken wrote: Re: [geo] Coupled Model Intercomparison Project 5 (CMIP5) simulations of climate following volcanic eruptions In my view, this is just why geoengineering efforts to cool the Arctic should consider as approaches: (a) spring-summer only injection of the appropriate sulfur compound (whatever will lead to sulfates) into the LOWER stratosphere or free troposphere, (b) cloud brightening in region or over currents carrying heat into the region, (c) approaches to brighten the surface albedo (e.g., microbubbles) in or near the region, and, perhaps, (d) approaches to reduce cirrus that are reducing IR loss. Parallel to these efforts, we should also be working to limit emissions of substances that amplify Arctic warming above and beyond the amplification that happens due to natural processes, so black carbon from sources in and near the region, etc. Mike On 9/11/12 5:03 AM, Stephen Salter s.sal...@ed.ac.uk wrote: Hi All Six out of the eight models in the Driscoll et al paper show near surface-warming in Arctic winters following volcanic eruptions. This is in line with figure 2a the Jones Hayward Boucher Robock 2010 paper in Atmospheric Chemistry and Physics. The obvious mechanisms are blanketing of outgoing radiation and side-scatter of high solar rays that might have missed the polar regions. Given the concerns about the loss of Arctic ice and increased methane release we will have to be very careful not to let any geo-engineering sulphur that we inject at low latitudes reach the Arctic in winter. Stephen On 10/09/2012 16:52, Simon Driscoll wrote: Dear all, the published version (no longer PiP) is now available here: http://www.agu.org/pubs/crossref/2012/2012JD017607.shtml Warm regards, Simon Simon Driscoll Atmospheric, Oceanic and Planetary Physics Department of Physics University of Oxford Office: 01865 272930 Mobile: 07935314940 http://www2.physics.ox.ac.uk/contacts/people/driscoll http://www.geoengineering.ox.ac.uk/people/who-are-we/simon-driscoll/ -- *From:* geoengineering@googlegroups.com [geoengineering@googlegroups.com] on behalf of Andrew Lockley [andrew.lock...@gmail.com] *Sent:* 14 August 2012 02:06 *To:* geoengineering *Subject:* [geo] Coupled Model Intercomparison Project 5 (CMIP5) simulations of climate following volcanic eruptions http://www.agu.org/pubs/crossref/pip/2012JD017607.shtml The ability of the climate models submitted to the Coupled Model Intercomparison Project 5 (CMIP5) database to simulate the Northern Hemisphere winter climate following a large tropical volcanic eruption
Re: [geo] Coupled Model Intercomparison Project 5 (CMIP5) simulations of climate following volcanic eruptions
As I understand it, the sulphur is mainly in the gas phase, whereas the BC is necessarily particulate. Therefore a cyclonic, electrostatic or conventional porous filter would probably do the trick. A On Sep 14, 2012 8:49 PM, John Nissen johnnissen2...@gmail.com wrote: Hi Mike, Could there be a method of selective filtering of coal-fired power stations, such that the cooling aerosol (or SO2 precursor) is allowed into the troposphere while the black carbon is removed? Cheers, John --- On Tue, Sep 11, 2012 at 7:15 PM, Mike MacCracken mmacc...@comcast.netwrote: Hi Stephen—I would think that Chinese sulfate (like tropospheric sulfate from virtually anywhere) would contribute to cloud and free air brightening, so a cooling influence (especially when that sulfate is above the dark Pacific Ocean). Now, in that coal plants put out more than pure SO2, there might well be some components (such as black carbon) that would exert a strong warming influence, especially if they are carried far enough to deposit on snow and/or ice during the sunny half of the year in the Arctic. For net effect, there is need for much more analysis than I have seen. On limiting heat reaching the Arctic Ocean, there have been suggestions to even build a dam across the Bering Strait—as long ago as the mid-20th century (though I think then it was with the intent to warm the Arctic). My guess on the kelp idea is that the sunny part of the year is not long enough for that approach to be all that practical (not only is the sunny part of the year short, but the sun angle is often not helpful). And sea ice is typically only a few meters thickness, so no where near 30 m. Mike On 9/11/12 12:48 PM, Stephen Salter s.sal...@ed.ac.uk wrote: Mike Do you think that the higher levels of SO2 from Chinese coal burning could account for some of the increase in Arctic temperatures? Another thought for your list might be to increase the drag of water flowing in through the Bering Strait. In summer kelp grows at an amazing rate but not below about 30 metre water depth because of the shortage of light. The net flow is 800,000 m3 a second and it will be warmer than polar water so a small velocity reduction makes a big difference. What if we put strong ropes moored at 30 metres to give them kelp a foot hold? If kelp gets scraped off by floating ice it will can grow again. Does ice reach down to 30 metres? Stephen On 11/09/2012 18:05, Mike MacCracken wrote: Re: [geo] Coupled Model Intercomparison Project 5 (CMIP5) simulations of climate following volcanic eruptions In my view, this is just why geoengineering efforts to cool the Arctic should consider as approaches: (a) spring-summer only injection of the appropriate sulfur compound (whatever will lead to sulfates) into the LOWER stratosphere or free troposphere, (b) cloud brightening in region or over currents carrying heat into the region, (c) approaches to brighten the surface albedo (e.g., microbubbles) in or near the region, and, perhaps, (d) approaches to reduce cirrus that are reducing IR loss. Parallel to these efforts, we should also be working to limit emissions of substances that amplify Arctic warming above and beyond the amplification that happens due to natural processes, so black carbon from sources in and near the region, etc. Mike On 9/11/12 5:03 AM, Stephen Salter s.sal...@ed.ac.uk wrote: Hi All Six out of the eight models in the Driscoll et al paper show near surface-warming in Arctic winters following volcanic eruptions. This is in line with figure 2a the Jones Hayward Boucher Robock 2010 paper in Atmospheric Chemistry and Physics. The obvious mechanisms are blanketing of outgoing radiation and side-scatter of high solar rays that might have missed the polar regions. Given the concerns about the loss of Arctic ice and increased methane release we will have to be very careful not to let any geo-engineering sulphur that we inject at low latitudes reach the Arctic in winter. Stephen On 10/09/2012 16:52, Simon Driscoll wrote: Dear all, the published version (no longer PiP) is now available here: http://www.agu.org/pubs/crossref/2012/2012JD017607.shtml Warm regards, Simon Simon Driscoll Atmospheric, Oceanic and Planetary Physics Department of Physics University of Oxford Office: 01865 272930 Mobile: 07935314940 http://www2.physics.ox.ac.uk/contacts/people/driscoll http://www.geoengineering.ox.ac.uk/people/who-are-we/simon-driscoll/ -- *From:* geoengineering@googlegroups.com [geoengineering@googlegroups.com] on behalf of Andrew Lockley [andrew.lock...@gmail.com] *Sent:* 14 August 2012 02:06 *To:* geoengineering *Subject:* [geo] Coupled Model Intercomparison Project 5 (CMIP5) simulations of climate following volcanic eruptions
Re: [geo] Coupled Model Intercomparison Project 5 (CMIP5) simulations of climate following volcanic eruptions
of the shortage of light. The net flow is 800,000 m3 a second and it will be warmer than polar water so a small velocity reduction makes a big difference. What if we put strong ropes moored at 30 metres to give them kelp a foot hold? If kelp gets scraped off by floating ice it will can grow again. Does ice reach down to 30 metres? Stephen On 11/09/2012 18:05, Mike MacCracken wrote: Re: [geo] Coupled Model Intercomparison Project 5 (CMIP5) simulations of climate following volcanic eruptions In my view, this is just why geoengineering efforts to cool the Arctic should consider as approaches: (a) spring-summer only injection of the appropriate sulfur compound (whatever will lead to sulfates) into the LOWER stratosphere or free troposphere, (b) cloud brightening in region or over currents carrying heat into the region, (c) approaches to brighten the surface albedo (e.g., microbubbles) in or near the region, and, perhaps, (d) approaches to reduce cirrus that are reducing IR loss. Parallel to these efforts, we should also be working to limit emissions of substances that amplify Arctic warming above and beyond the amplification that happens due to natural processes, so black carbon from sources in and near the region, etc. Mike On 9/11/12 5:03 AM, Stephen Salter s.sal...@ed.ac.uk http://s.sal...@ed.ac.uk wrote: Hi All Six out of the eight models in the Driscoll et al paper show near surface-warming in Arctic winters following volcanic eruptions. This is in line with figure 2a the Jones Hayward Boucher Robock 2010 paper in Atmospheric Chemistry and Physics. The obvious mechanisms are blanketing of outgoing radiation and side-scatter of high solar rays that might have missed the polar regions. Given the concerns about the loss of Arctic ice and increased methane release we will have to be very careful not to let any geo-engineering sulphur that we inject at low latitudes reach the Arctic in winter. Stephen On 10/09/2012 16:52, Simon Driscoll wrote: Dear all, the published version (no longer PiP) is now available here: http://www.agu.org/pubs/crossref/2012/2012JD017607.shtml Warm regards, Simon Simon Driscoll Atmospheric, Oceanic and Planetary Physics Department of Physics University of Oxford Office: 01865 272930 Mobile: 07935314940 http://www2.physics.ox.ac.uk/contacts/people/driscoll http://www.geoengineering.ox.ac.uk/people/who-are-we/simon-driscoll/ From: geoengineering@googlegroups.com http://geoengineering@googlegroups.com [geoengineering@googlegroups.com http://geoengineering@googlegroups.com ] on behalf of Andrew Lockley [andrew.lock...@gmail.com http://andrew.lock...@gmail.com ] Sent: 14 August 2012 02:06 To: geoengineering Subject: [geo] Coupled Model Intercomparison Project 5 (CMIP5) simulations of climate following volcanic eruptions http://www.agu.org/pubs/crossref/pip/2012JD017607.shtml The ability of the climate models submitted to the Coupled Model Intercomparison Project 5 (CMIP5) database to simulate the Northern Hemisphere winter climate following a large tropical volcanic eruption is assessed. When sulfate aerosols are produced by volcanic injections into the tropical stratosphere and spread by the stratospheric circulation, it not only causes globally averaged tropospheric cooling but also a localized heating in the lower stratosphere, which can cause major dynamical feedbacks. Observations show a lower stratospheric and surface response during the following one or two Northern Hemisphere (NH) winters, that resembles the positive phase of the North Atlantic Oscillation (NAO). Simulations from 13 CMIP5 models that represent tropical eruptions in the 19th and 20th century are examined, focusing on the large-scale regional impacts associated with the large-scale circulation during the NH winter season. The models generally fail to capture the NH dynamical response following eruptions. They do not sufficiently simulate the observed post-volcanic strengthened NH polar vortex, positive NAO, or NH Eurasian warming pattern, and they tend to overestimate the cooling in the tropical troposphere. The findings are confirmed by a superposed epoch analysis of the NAO index for each model. The study confirms previous similar evaluations and raises concern for the ability of current climate models to simulate the response of a major mode of global circulation variability to external forcings. This is also of concern for the accuracy of geoengineering modeling studies that assess the atmospheric response to stratosphere-injected particles.Received 13 February 2012; accepted 24 July 2012. -- You received this message because you are subscribed
Re: [geo] Coupled Model Intercomparison Project 5 (CMIP5) simulations of climate following volcanic eruptions
Hi All Six out of the eight models in the Driscoll et al paper show near surface-warming in Arctic winters following volcanic eruptions. This is in line with figure 2a the Jones Hayward Boucher Robock 2010 paper in Atmospheric Chemistry and Physics. The obvious mechanisms are blanketing of outgoing radiation and side-scatter of high solar rays that might have missed the polar regions. Given the concerns about the loss of Arctic ice and increased methane release we will have to be very careful not to let any geo-engineering sulphur that we inject at low latitudes reach the Arctic in winter. Stephen On 10/09/2012 16:52, Simon Driscoll wrote: Dear all, the published version (no longer PiP) is now available here: http://www.agu.org/pubs/crossref/2012/2012JD017607.shtml Warm regards, Simon Simon Driscoll Atmospheric, Oceanic and Planetary Physics Department of Physics University of Oxford Office: 01865 272930 Mobile: 07935314940 http://www2.physics.ox.ac.uk/contacts/people/driscoll http://www.geoengineering.ox.ac.uk/people/who-are-we/simon-driscoll/ *From:* geoengineering@googlegroups.com [geoengineering@googlegroups.com] on behalf of Andrew Lockley [andrew.lock...@gmail.com] *Sent:* 14 August 2012 02:06 *To:* geoengineering *Subject:* [geo] Coupled Model Intercomparison Project 5 (CMIP5) simulations of climate following volcanic eruptions http://www.agu.org/pubs/crossref/pip/2012JD017607.shtml The ability of the climate models submitted to the Coupled Model Intercomparison Project 5 (CMIP5) database to simulate the Northern Hemisphere winter climate following a large tropical volcanic eruption is assessed. When sulfate aerosols are produced by volcanic injections into the tropical stratosphere and spread by the stratospheric circulation, it not only causes globally averaged tropospheric cooling but also a localized heating in the lower stratosphere, which can cause major dynamical feedbacks. Observations show a lower stratospheric and surface response during the following one or two Northern Hemisphere (NH) winters, that resembles the positive phase of the North Atlantic Oscillation (NAO). Simulations from 13 CMIP5 models that represent tropical eruptions in the 19th and 20th century are examined, focusing on the large-scale regional impacts associated with the large-scale circulation during the NH winter season. The models generally fail to capture the NH dynamical response following eruptions. They do not sufficiently simulate the observed post-volcanic strengthened NH polar vortex, positive NAO, or NH Eurasian warming pattern, and they tend to overestimate the cooling in the tropical troposphere. The findings are confirmed by a superposed epoch analysis of the NAO index for each model. The study confirms previous similar evaluations and raises concern for the ability of current climate models to simulate the response of a major mode of global circulation variability to external forcings. This is also of concern for the accuracy of geoengineering modeling studies that assess the atmospheric response to stratosphere-injected particles.Received 13 February 2012; accepted 24 July 2012. -- You received this message because you are subscribed to the Google Groups geoengineering group. To post to this group, send email to geoengineering@googlegroups.com. To unsubscribe from this group, send email to geoengineering+unsubscr...@googlegroups.com. For more options, visit this group at http://groups.google.com/group/geoengineering?hl=en. -- You received this message because you are subscribed to the Google Groups geoengineering group. To post to this group, send email to geoengineering@googlegroups.com. To unsubscribe from this group, send email to geoengineering+unsubscr...@googlegroups.com. For more options, visit this group at http://groups.google.com/group/geoengineering?hl=en. -- Emeritus Professor of Engineering Design School of Engineering University of Edinburgh Mayfield Road Edinburgh EH9 3JL Scotland s.sal...@ed.ac.uk Tel +44 (0)131 650 5704 Cell 07795 203 195 WWW.see.ed.ac.uk/~shs The University of Edinburgh is a charitable body, registered in Scotland, with registration number SC005336. -- You received this message because you are subscribed to the Google Groups geoengineering group. To post to this group, send email to geoengineering@googlegroups.com. To unsubscribe from this group, send email to geoengineering+unsubscr...@googlegroups.com. For more options, visit this group at http://groups.google.com/group/geoengineering?hl=en.
Re: [geo] Coupled Model Intercomparison Project 5 (CMIP5) simulations of climate following volcanic eruptions
If the effect is unavoidably year round, what's the sign on the sea ice net effect? Thus may be different to temp. A On Sep 11, 2012 10:03 AM, Stephen Salter s.sal...@ed.ac.uk wrote: Hi All Six out of the eight models in the Driscoll et al paper show near surface-warming in Arctic winters following volcanic eruptions. This is in line with figure 2a the Jones Hayward Boucher Robock 2010 paper in Atmospheric Chemistry and Physics. The obvious mechanisms are blanketing of outgoing radiation and side-scatter of high solar rays that might have missed the polar regions. Given the concerns about the loss of Arctic ice and increased methane release we will have to be very careful not to let any geo-engineering sulphur that we inject at low latitudes reach the Arctic in winter. Stephen On 10/09/2012 16:52, Simon Driscoll wrote: Dear all, the published version (no longer PiP) is now available here: http://www.agu.org/pubs/crossref/2012/2012JD017607.shtml Warm regards, Simon Simon Driscoll Atmospheric, Oceanic and Planetary Physics Department of Physics University of Oxford Office: 01865 272930 Mobile: 07935314940 http://www2.physics.ox.ac.uk/contacts/people/driscoll http://www.geoengineering.ox.ac.uk/people/who-are-we/simon-driscoll/ -- *From:* geoengineering@googlegroups.com [geoengineering@googlegroups.com] on behalf of Andrew Lockley [andrew.lock...@gmail.com] *Sent:* 14 August 2012 02:06 *To:* geoengineering *Subject:* [geo] Coupled Model Intercomparison Project 5 (CMIP5) simulations of climate following volcanic eruptions http://www.agu.org/pubs/crossref/pip/2012JD017607.shtml The ability of the climate models submitted to the Coupled Model Intercomparison Project 5 (CMIP5) database to simulate the Northern Hemisphere winter climate following a large tropical volcanic eruption is assessed. When sulfate aerosols are produced by volcanic injections into the tropical stratosphere and spread by the stratospheric circulation, it not only causes globally averaged tropospheric cooling but also a localized heating in the lower stratosphere, which can cause major dynamical feedbacks. Observations show a lower stratospheric and surface response during the following one or two Northern Hemisphere (NH) winters, that resembles the positive phase of the North Atlantic Oscillation (NAO). Simulations from 13 CMIP5 models that represent tropical eruptions in the 19th and 20th century are examined, focusing on the large-scale regional impacts associated with the large-scale circulation during the NH winter season. The models generally fail to capture the NH dynamical response following eruptions. They do not sufficiently simulate the observed post-volcanic strengthened NH polar vortex, positive NAO, or NH Eurasian warming pattern, and they tend to overestimate the cooling in the tropical troposphere. The findings are confirmed by a superposed epoch analysis of the NAO index for each model. The study confirms previous similar evaluations and raises concern for the ability of current climate models to simulate the response of a major mode of global circulation variability to external forcings. This is also of concern for the accuracy of geoengineering modeling studies that assess the atmospheric response to stratosphere-injected particles.Received 13 February 2012; accepted 24 July 2012. -- You received this message because you are subscribed to the Google Groups geoengineering group. To post to this group, send email to geoengineering@googlegroups.com. To unsubscribe from this group, send email to geoengineering+unsubscr...@googlegroups.com. For more options, visit this group at http://groups.google.com/group/geoengineering?hl=en. -- You received this message because you are subscribed to the Google Groups geoengineering group. To post to this group, send email to geoengineering@googlegroups.com. To unsubscribe from this group, send email to geoengineering+unsubscr...@googlegroups.com. For more options, visit this group at http://groups.google.com/group/geoengineering?hl=en. -- Emeritus Professor of Engineering Design School of Engineering University of Edinburgh Mayfield Road Edinburgh EH9 3JL Scotland s.sal...@ed.ac.ukTel +44 (0)131 650 5704 Cell 07795 203 195 WWW.see.ed.ac.uk/~shs The University of Edinburgh is a charitable body, registered in Scotland, with registration number SC005336. -- You received this message because you are subscribed to the Google Groups geoengineering group. To post to this group, send email to geoengineering@googlegroups.com. To unsubscribe from this group, send email to geoengineering+unsubscr...@googlegroups.com. For more options, visit this group at http://groups.google.com/group/geoengineering?hl=en. -- You received this message because you are subscribed to the Google Groups geoengineering
Re: [geo] Coupled Model Intercomparison Project 5 (CMIP5) simulations of climate following volcanic eruptions
Dear Steve, What is obvious to you is not to any climatologists. Please refrain from such speculation if you can't back it up with the physics of the climate system. The mechanism for temperature change you describe is wrong. And you could not keep stratospheric sulfur injected into the tropics from reaching the Arctic, but since that is not how it works, this is not a reason to be concerned with stratospheric geoengineering. There are many other reasons to be concerned, but this is not one. Alan Alan Robock, Professor II (Distinguished Professor) Editor, Reviews of Geophysics Director, Meteorology Undergraduate Program Associate Director, Center for Environmental Prediction Department of Environmental Sciences Phone: +1-848-932-5751 Rutgers University Fax: +1-732-932-8644 14 College Farm Road E-mail: rob...@envsci.rutgers.edu New Brunswick, NJ 08901-8551 USA http://envsci.rutgers.edu/~robock On 9/11/2012 5:03 AM, Stephen Salter wrote: Hi All Six out of the eight models in the Driscoll et al paper show near surface-warming in Arctic winters following volcanic eruptions. This is in line with figure 2a the Jones Hayward Boucher Robock 2010 paper in Atmospheric Chemistry and Physics. The obvious mechanisms are blanketing of outgoing radiation and side-scatter of high solar rays that might have missed the polar regions. Given the concerns about the loss of Arctic ice and increased methane release we will have to be very careful not to let any geo-engineering sulphur that we inject at low latitudes reach the Arctic in winter. Stephen On 10/09/2012 16:52, Simon Driscoll wrote: Dear all, the published version (no longer PiP) is now available here: http://www.agu.org/pubs/crossref/2012/2012JD017607.shtml Warm regards, Simon Simon Driscoll Atmospheric, Oceanic and Planetary Physics Department of Physics University of Oxford Office: 01865 272930 Mobile: 07935314940 http://www2.physics.ox.ac.uk/contacts/people/driscoll http://www.geoengineering.ox.ac.uk/people/who-are-we/simon-driscoll/ *From:* geoengineering@googlegroups.com [geoengineering@googlegroups.com] on behalf of Andrew Lockley [andrew.lock...@gmail.com] *Sent:* 14 August 2012 02:06 *To:* geoengineering *Subject:* [geo] Coupled Model Intercomparison Project 5 (CMIP5) simulations of climate following volcanic eruptions http://www.agu.org/pubs/crossref/pip/2012JD017607.shtml The ability of the climate models submitted to the Coupled Model Intercomparison Project 5 (CMIP5) database to simulate the Northern Hemisphere winter climate following a large tropical volcanic eruption is assessed. When sulfate aerosols are produced by volcanic injections into the tropical stratosphere and spread by the stratospheric circulation, it not only causes globally averaged tropospheric cooling but also a localized heating in the lower stratosphere, which can cause major dynamical feedbacks. Observations show a lower stratospheric and surface response during the following one or two Northern Hemisphere (NH) winters, that resembles the positive phase of the North Atlantic Oscillation (NAO). Simulations from 13 CMIP5 models that represent tropical eruptions in the 19th and 20th century are examined, focusing on the large-scale regional impacts associated with the large-scale circulation during the NH winter season. The models generally fail to capture the NH dynamical response following eruptions. They do not sufficiently simulate the observed post-volcanic strengthened NH polar vortex, positive NAO, or NH Eurasian warming pattern, and they tend to overestimate the cooling in the tropical troposphere. The findings are confirmed by a superposed epoch analysis of the NAO index for each model. The study confirms previous similar evaluations and raises concern for the ability of current climate models to simulate the response of a major mode of global circulation variability to external forcings. This is also of concern for the accuracy of geoengineering modeling studies that assess the atmospheric response to stratosphere-injected particles.Received 13 February 2012; accepted 24 July 2012. -- You received this message because you are subscribed to the Google Groups geoengineering group. To post to this group, send email to geoengineering@googlegroups.com. To unsubscribe from this group, send email to geoengineering+unsubscr...@googlegroups.com. For more options, visit this group at http://groups.google.com/group/geoengineering?hl=en. -- You received this message because you are subscribed to the Google Groups geoengineering group. To post to this group, send email to geoengineering@googlegroups.com. To unsubscribe from this group, send email to geoengineering+unsubscr...@googlegroups.com. For more
Re: [geo] Coupled Model Intercomparison Project 5 (CMIP5) simulations of climate following volcanic eruptions
In my view, this is just why geoengineering efforts to cool the Arctic should consider as approaches: (a) spring-summer only injection of the appropriate sulfur compound (whatever will lead to sulfates) into the LOWER stratosphere or free troposphere, (b) cloud brightening in region or over currents carrying heat into the region, (c) approaches to brighten the surface albedo (e.g., microbubbles) in or near the region, and, perhaps, (d) approaches to reduce cirrus that are reducing IR loss. Parallel to these efforts, we should also be working to limit emissions of substances that amplify Arctic warming above and beyond the amplification that happens due to natural processes, so black carbon from sources in and near the region, etc. Mike On 9/11/12 5:03 AM, Stephen Salter s.sal...@ed.ac.uk wrote: Hi All Six out of the eight models in the Driscoll et al paper show near surface-warming in Arctic winters following volcanic eruptions. This is in line with figure 2a the Jones Hayward Boucher Robock 2010 paper in Atmospheric Chemistry and Physics. The obvious mechanisms are blanketing of outgoing radiation and side-scatter of high solar rays that might have missed the polar regions. Given the concerns about the loss of Arctic ice and increased methane release we will have to be very careful not to let any geo-engineering sulphur that we inject at low latitudes reach the Arctic in winter. Stephen On 10/09/2012 16:52, Simon Driscoll wrote: Dear all, the published version (no longer PiP) is now available here: http://www.agu.org/pubs/crossref/2012/2012JD017607.shtml Warm regards, Simon Simon Driscoll Atmospheric, Oceanic and Planetary Physics Department of Physics University of Oxford Office: 01865 272930 Mobile: 07935314940 http://www2.physics.ox.ac.uk/contacts/people/driscoll http://www.geoengineering.ox.ac.uk/people/who-are-we/simon-driscoll/ From: geoengineering@googlegroups.com [geoengineering@googlegroups.com] on behalf of Andrew Lockley [andrew.lock...@gmail.com] Sent: 14 August 2012 02:06 To: geoengineering Subject: [geo] Coupled Model Intercomparison Project 5 (CMIP5) simulations of climate following volcanic eruptions http://www.agu.org/pubs/crossref/pip/2012JD017607.shtml The ability of the climate models submitted to the Coupled Model Intercomparison Project 5 (CMIP5) database to simulate the Northern Hemisphere winter climate following a large tropical volcanic eruption is assessed. When sulfate aerosols are produced by volcanic injections into the tropical stratosphere and spread by the stratospheric circulation, it not only causes globally averaged tropospheric cooling but also a localized heating in the lower stratosphere, which can cause major dynamical feedbacks. Observations show a lower stratospheric and surface response during the following one or two Northern Hemisphere (NH) winters, that resembles the positive phase of the North Atlantic Oscillation (NAO). Simulations from 13 CMIP5 models that represent tropical eruptions in the 19th and 20th century are examined, focusing on the large-scale regional impacts associated with the large-scale circulation during the NH winter season. The models generally fail to capture the NH dynamical response following eruptions. They do not sufficiently simulate the observed post-volcanic strengthened NH polar vortex, positive NAO, or NH Eurasian warming pattern, and they tend to overestimate the cooling in the tropical troposphere. The findings are confirmed by a superposed epoch analysis of the NAO index for each model. The study confirms previous similar evaluations and raises concern for the ability of current climate models to simulate the response of a major mode of global circulation variability to external forcings. This is also of concern for the accuracy of geoengineering modeling studies that assess the atmospheric response to stratosphere-injected particles.Received 13 February 2012; accepted 24 July 2012. -- You received this message because you are subscribed to the Google Groups geoengineering group. To post to this group, send email to geoengineering@googlegroups.com. To unsubscribe from this group, send email to geoengineering+unsubscr...@googlegroups.com. For more options, visit this group at http://groups.google.com/group/geoengineering?hl=en. -- You received this message because you are subscribed to the Google Groups geoengineering group. To post to this group, send email to geoengineering@googlegroups.com. To unsubscribe from this group, send email to geoengineering+unsubscr...@googlegroups.com. For more options, visit this group at http://groups.google.com/group/geoengineering?hl=en. -- You received this message because you are subscribed to the Google
Re: [geo] Coupled Model Intercomparison Project 5 (CMIP5) simulations of climate following volcanic eruptions
Hi Andrew--The key is to limit heat uptake by the Arctic Ocean, which takes up the energy in the sunny season and then releases it to the atmosphere in the winter, causing warming. Sea ice reflects solar when present during the summer season, but tends to retain heat in the Arctic during the dark season (i.e., slowing transfer of heat from ocean to atmosphere and then, at least for some fraction, out to space). Mike On 9/11/12 6:06 AM, Andrew Lockley andrew.lock...@gmail.com wrote: If the effect is unavoidably year round, what's the sign on the sea ice net effect? Thus may be different to temp. A On Sep 11, 2012 10:03 AM, Stephen Salter s.sal...@ed.ac.uk wrote: Hi All Six out of the eight models in the Driscoll et al paper show near surface-warming in Arctic winters following volcanic eruptions. This is in line with figure 2a the Jones Hayward Boucher Robock 2010 paper in Atmospheric Chemistry and Physics. The obvious mechanisms are blanketing of outgoing radiation and side-scatter of high solar rays that might have missed the polar regions. Given the concerns about the loss of Arctic ice and increased methane release we will have to be very careful not to let any geo-engineering sulphur that we inject at low latitudes reach the Arctic in winter. Stephen On 10/09/2012 16:52, Simon Driscoll wrote: Dear all, the published version (no longer PiP) is now available here: http://www.agu.org/pubs/crossref/2012/2012JD017607.shtml Warm regards, Simon Simon Driscoll Atmospheric, Oceanic and Planetary Physics Department of Physics University of Oxford Office: 01865 272930 Mobile: 07935314940 http://www2.physics.ox.ac.uk/contacts/people/driscoll http://www.geoengineering.ox.ac.uk/people/who-are-we/simon-driscoll/ From: geoengineering@googlegroups.com [geoengineering@googlegroups.com] on behalf of Andrew Lockley [andrew.lock...@gmail.com] Sent: 14 August 2012 02:06 To: geoengineering Subject: [geo] Coupled Model Intercomparison Project 5 (CMIP5) simulations of climate following volcanic eruptions http://www.agu.org/pubs/crossref/pip/2012JD017607.shtml The ability of the climate models submitted to the Coupled Model Intercomparison Project 5 (CMIP5) database to simulate the Northern Hemisphere winter climate following a large tropical volcanic eruption is assessed. When sulfate aerosols are produced by volcanic injections into the tropical stratosphere and spread by the stratospheric circulation, it not only causes globally averaged tropospheric cooling but also a localized heating in the lower stratosphere, which can cause major dynamical feedbacks. Observations show a lower stratospheric and surface response during the following one or two Northern Hemisphere (NH) winters, that resembles the positive phase of the North Atlantic Oscillation (NAO). Simulations from 13 CMIP5 models that represent tropical eruptions in the 19th and 20th century are examined, focusing on the large-scale regional impacts associated with the large-scale circulation during the NH winter season. The models generally fail to capture the NH dynamical response following eruptions. They do not sufficiently simulate the observed post-volcanic strengthened NH polar vortex, positive NAO, or NH Eurasian warming pattern, and they tend to overestimate the cooling in the tropical troposphere. The findings are confirmed by a superposed epoch analysis of the NAO index for each model. The study confirms previous similar evaluations and raises concern for the ability of current climate models to simulate the response of a major mode of global circulation variability to external forcings. This is also of concern for the accuracy of geoengineering modeling studies that assess the atmospheric response to stratosphere-injected particles.Received 13 February 2012; accepted 24 July 2012. -- You received this message because you are subscribed to the Google Groups geoengineering group. To post to this group, send email to geoengineering@googlegroups.com. To unsubscribe from this group, send email to geoengineering+unsubscr...@googlegroups.com. For more options, visit this group at http://groups.google.com/group/geoengineering?hl=en. -- You received this message because you are subscribed to the Google Groups geoengineering group. To post to this group, send email to geoengineering@googlegroups.com. To unsubscribe from this group, send email to geoengineering+unsubscr...@googlegroups.com. For more options, visit this group at http://groups.google.com/group/geoengineering?hl=en. -- You received this message because you are subscribed to the Google Groups geoengineering group. To post to this group, send email to geoengineering@googlegroups.com. To unsubscribe from
Re: [geo] Coupled Model Intercomparison Project 5 (CMIP5) simulations of climate following volcanic eruptions
Mike Do you think that the higher levels of SO2 from Chinese coal burning could account for some of the increase in Arctic temperatures? Another thought for your list might be to increase the drag of water flowing in through the Bering Strait. In summer kelp grows at an amazing rate but not below about 30 metre water depth because of the shortage of light. The net flow is 800,000 m3 a second and it will be warmer than polar water so a small velocity reduction makes a big difference. What if we put strong ropes moored at 30 metres to give them kelp a foot hold? If kelp gets scraped off by floating ice it will can grow again. Does ice reach down to 30 metres? Stephen On 11/09/2012 18:05, Mike MacCracken wrote: Re: [geo] Coupled Model Intercomparison Project 5 (CMIP5) simulations of climate following volcanic eruptions In my view, this is just why geoengineering efforts to cool the Arctic should consider as approaches: (a) spring-summer only injection of the appropriate sulfur compound (whatever will lead to sulfates) into the LOWER stratosphere or free troposphere, (b) cloud brightening in region or over currents carrying heat into the region, (c) approaches to brighten the surface albedo (e.g., microbubbles) in or near the region, and, perhaps, (d) approaches to reduce cirrus that are reducing IR loss. Parallel to these efforts, we should also be working to limit emissions of substances that amplify Arctic warming above and beyond the amplification that happens due to natural processes, so black carbon from sources in and near the region, etc. Mike On 9/11/12 5:03 AM, Stephen Salter s.sal...@ed.ac.uk wrote: Hi All Six out of the eight models in the Driscoll et al paper show near surface-warming in Arctic winters following volcanic eruptions. This is in line with figure 2a the Jones Hayward Boucher Robock 2010 paper in Atmospheric Chemistry and Physics. The obvious mechanisms are blanketing of outgoing radiation and side-scatter of high solar rays that might have missed the polar regions. Given the concerns about the loss of Arctic ice and increased methane release we will have to be very careful not to let any geo-engineering sulphur that we inject at low latitudes reach the Arctic in winter. Stephen On 10/09/2012 16:52, Simon Driscoll wrote: Dear all, the published version (no longer PiP) is now available here: http://www.agu.org/pubs/crossref/2012/2012JD017607.shtml Warm regards, Simon Simon Driscoll Atmospheric, Oceanic and Planetary Physics Department of Physics University of Oxford Office: 01865 272930 Mobile: 07935314940 http://www2.physics.ox.ac.uk/contacts/people/driscoll http://www.geoengineering.ox.ac.uk/people/who-are-we/simon-driscoll/ *From:*geoengineering@googlegroups.com [geoengineering@googlegroups.com] on behalf of Andrew Lockley [andrew.lock...@gmail.com] *Sent:* 14 August 2012 02:06 *To:* geoengineering *Subject:* [geo] Coupled Model Intercomparison Project 5 (CMIP5) simulations of climate following volcanic eruptions http://www.agu.org/pubs/crossref/pip/2012JD017607.shtml The ability of the climate models submitted to the Coupled Model Intercomparison Project 5 (CMIP5) database to simulate the Northern Hemisphere winter climate following a large tropical volcanic eruption is assessed. When sulfate aerosols are produced by volcanic injections into the tropical stratosphere and spread by the stratospheric circulation, it not only causes globally averaged tropospheric cooling but also a localized heating in the lower stratosphere, which can cause major dynamical feedbacks. Observations show a lower stratospheric and surface response during the following one or two Northern Hemisphere (NH) winters, that resembles the positive phase of the North Atlantic Oscillation (NAO). Simulations from 13 CMIP5 models that represent tropical eruptions in the 19th and 20th century are examined, focusing on the large-scale regional impacts associated with the large-scale circulation during the NH winter season. The models generally fail to capture the NH dynamical response following eruptions. They do not sufficiently simulate the observed post-volcanic strengthened NH polar vortex, positive NAO, or NH Eurasian warming pattern, and they tend to overestimate the cooling in the tropical troposphere. The findings are confirmed by a superposed epoch analysis of the NAO index for each model
RE: [geo] Coupled Model Intercomparison Project 5 (CMIP5) simulations of climate following volcanic eruptions
Dear all, the published version (no longer PiP) is now available here: http://www.agu.org/pubs/crossref/2012/2012JD017607.shtml Warm regards, Simon Simon Driscoll Atmospheric, Oceanic and Planetary Physics Department of Physics University of Oxford Office: 01865 272930 Mobile: 07935314940 http://www2.physics.ox.ac.uk/contacts/people/driscoll http://www.geoengineering.ox.ac.uk/people/who-are-we/simon-driscoll/ From: geoengineering@googlegroups.com [geoengineering@googlegroups.com] on behalf of Andrew Lockley [andrew.lock...@gmail.com] Sent: 14 August 2012 02:06 To: geoengineering Subject: [geo] Coupled Model Intercomparison Project 5 (CMIP5) simulations of climate following volcanic eruptions http://www.agu.org/pubs/crossref/pip/2012JD017607.shtml The ability of the climate models submitted to the Coupled Model Intercomparison Project 5 (CMIP5) database to simulate the Northern Hemisphere winter climate following a large tropical volcanic eruption is assessed. When sulfate aerosols are produced by volcanic injections into the tropical stratosphere and spread by the stratospheric circulation, it not only causes globally averaged tropospheric cooling but also a localized heating in the lower stratosphere, which can cause major dynamical feedbacks. Observations show a lower stratospheric and surface response during the following one or two Northern Hemisphere (NH) winters, that resembles the positive phase of the North Atlantic Oscillation (NAO). Simulations from 13 CMIP5 models that represent tropical eruptions in the 19th and 20th century are examined, focusing on the large-scale regional impacts associated with the large-scale circulation during the NH winter season. The models generally fail to capture the NH dynamical response following eruptions. They do not sufficiently simulate the observed post-volcanic strengthened NH polar vortex, positive NAO, or NH Eurasian warming pattern, and they tend to overestimate the cooling in the tropical troposphere. The findings are confirmed by a superposed epoch analysis of the NAO index for each model. The study confirms previous similar evaluations and raises concern for the ability of current climate models to simulate the response of a major mode of global circulation variability to external forcings. This is also of concern for the accuracy of geoengineering modeling studies that assess the atmospheric response to stratosphere-injected particles.Received 13 February 2012; accepted 24 July 2012. -- You received this message because you are subscribed to the Google Groups geoengineering group. To post to this group, send email to geoengineering@googlegroups.com. To unsubscribe from this group, send email to geoengineering+unsubscr...@googlegroups.com. For more options, visit this group at http://groups.google.com/group/geoengineering?hl=en. -- You received this message because you are subscribed to the Google Groups geoengineering group. To post to this group, send email to geoengineering@googlegroups.com. To unsubscribe from this group, send email to geoengineering+unsubscr...@googlegroups.com. For more options, visit this group at http://groups.google.com/group/geoengineering?hl=en.
[geo] Coupled Model Intercomparison Project 5 (CMIP5) simulations of climate following volcanic eruptions
http://www.agu.org/pubs/crossref/pip/2012JD017607.shtml The ability of the climate models submitted to the Coupled Model Intercomparison Project 5 (CMIP5) database to simulate the Northern Hemisphere winter climate following a large tropical volcanic eruption is assessed. When sulfate aerosols are produced by volcanic injections into the tropical stratosphere and spread by the stratospheric circulation, it not only causes globally averaged tropospheric cooling but also a localized heating in the lower stratosphere, which can cause major dynamical feedbacks. Observations show a lower stratospheric and surface response during the following one or two Northern Hemisphere (NH) winters, that resembles the positive phase of the North Atlantic Oscillation (NAO). Simulations from 13 CMIP5 models that represent tropical eruptions in the 19th and 20th century are examined, focusing on the large-scale regional impacts associated with the large-scale circulation during the NH winter season. The models generally fail to capture the NH dynamical response following eruptions. They do not sufficiently simulate the observed post-volcanic strengthened NH polar vortex, positive NAO, or NH Eurasian warming pattern, and they tend to overestimate the cooling in the tropical troposphere. The findings are confirmed by a superposed epoch analysis of the NAO index for each model. The study confirms previous similar evaluations and raises concern for the ability of current climate models to simulate the response of a major mode of global circulation variability to external forcings. This is also of concern for the accuracy of geoengineering modeling studies that assess the atmospheric response to stratosphere-injected particles.Received 13 February 2012; accepted 24 July 2012. -- You received this message because you are subscribed to the Google Groups geoengineering group. To post to this group, send email to geoengineering@googlegroups.com. To unsubscribe from this group, send email to geoengineering+unsubscr...@googlegroups.com. For more options, visit this group at http://groups.google.com/group/geoengineering?hl=en.
