[geo] SRM = bandaid, CDR = cure
http://www.skepticalscience.com/print.php?n=1785 No alternative to atmospheric CO2 draw-down This article suggests that the current atmospheric CO2 level is already triggering amplifying feedbacks from the Earth system and therefore, in themselves, efforts at reduction in atmospheric CO2-emission are no longer sufficient to prevent further global warming. For this reason, along with sharp reductions in carbon emissions, efforts need to be undertaken in an attempt to reduce atmospheric CO2 levels from their current level of near-400 ppm to well below 350 ppm. NASA-applied outer space-shade technology may buy time for such planetary defense effort. The scale and rate of modern climate change have been greatly underestimated. The release to date of a total of over 560 billion ton of carbon through emissions from industrial and transport sources, land clearing and fires, has raised CO2 levels from about 280 parts per million (ppm) in pre-industrial periods to 397-400 ppm and near 470 ppm CO2-equivalent (a value which includes the CO2-equivalent effect of methane), reaching a current CO2 growth rate of about 2 ppm per yearhttp://www.globalcarbonproject.org/ [http://www.skepticalscience.com/pics/glikson_figure1.gif] Figure 1: Part A. Mean CO2 level from ice cores, Mouna Loa observatory and marine sites; Part B (inset). Climate forcing 1880 - 2003http://pubs.giss.nasa.gov/abs/ha06510a.html. Aerosol forcing includes all aerosol effects, including indirect effects on clouds and snow albedo. GHGs include ozone (O3) and stratospheric H2O, in addition to well-mixed greenhouse gases. [http://www.skepticalscience.com/pics/glikson_figure2.gif] Figure 2: Relations between CO2 rise rates and mean global temperature rise rates during warming periodshttp://cci.anu.edu.au/files/download/?id=4951, including the Paleocene-Eocene Thermal Maximum, Oligocene, Miocene, glacial terminations, Dansgaard-Oeschger cycles and the post-1750 period. These developments are shifting the Earth's climate toward Pliocene-like (5.2 - 2.6 million years-ago; mean global temperatures of +2-3oC above pre-industrial temperatures) and possibly toward mid-Miocene-like (approximately 16 million years-ago; mean global temperatures +4oC above pre-industrial temperatureshttp://www.nature.com/ngeo/journal/v4/n7/fig_tab/ngeo1186_ft.html) conditions within a few centuries--a geological blink of an eye. The current CO2 level generates amplifying feedbacks, including the reduced capacity of warming water to absorb CO2 from the atmosphere, CO2 released from fires, droughts, loss of vegetation cover, disintegration of methane released from bogs, permafrost and methane-bearing ice particles and methane-water molecules. With CO2 atmospheric residence times in the order of thousands to tens of thousands yearshttp://www.pnas.org/content/early/2009/01/28/0812721106.abstract, protracted reduction in emissions, either flowing from human decision or due to reduced economic activity in an environmentally stressed world, may no longer be sufficient to arrest the feedbacks. Four of the large mass extinction of species events in the history of Earth (end-Devonian, Permian-Triassic, end-Triassic, K-T boundary) have been associated with rapid perturbations of the carbon, oxygen and sulphur cycles, on which the biosphere depends, at rates to which species could not adapthttp://theconversation.edu.au/is-another-mass-extinction-event-on-the-way-5397. Since the 18th century, and in particular since about 1975, the Earth system has been shifting away from Holocene (approximately 10,000 years to the pre-industrial time) conditions, which allowed agriculture, previously hindered by instabilities in the climate and by extreme weather events. The shift is most clearly manifested by the loss of polar icehttp://www.agu.org/pubs/crossref/2011/2011GL046583.shtml. Sea level rises have been accelerating, with a total of more than 20 cm since 1880 and about 6 cm since 1990http://www.eea.europa.eu/data-and-maps/indicators/sea-level-rise-1/assessment. For temperature rise of 2.3oC, to which the climate is committed if sulphur aerosol emission discontinueshttp://pubs.giss.nasa.gov/abs/ha06510a.html (see Figure 1), sea levels would reach Pliocene-like levels of 25 meters plus or minus 12 meters, with lag effects due to ice sheet hysteresis (system inertia). With global atmospheric CO2-equivalent (a value which includes the effect of methane) above 470 ppm, just under the upper stability limit of the Antarctic ice sheethttp://www.columbia.edu/~jeh1/2008/TargetCO2_20080407.pdf, with current rate of CO2 emissions from fossil fuel combustion, cement production, land clearing and fires of ~9.7 billion ton of carbon in 2010http://www.science.org.au/natcoms/nc-ess/documents/GEsymposium.pdf, global civilization faces the following alternatives: 1. With carbon reserves sufficient to raise atmospheric CO2 levels to above 1000
Re: [geo] Brief Summary Marine Geoengineering Techniques
Chris and list: 1. Thanks for forwarding your interesting 4-pager on marine engineering. I respond here only from the perspective of biochar. 2. On your p 2, the word biochar appears this way: Depositing crop wastes on the deep seabed – Strand and Benford (2009) have proposed depositing bales of terrestrial crop wastes on the deep seabed and this could potentially be extended to include depositing biochar/charcoal or other organic remains. I have seen once an oblique reference (I might not be able to find now) to biochar possibly being beneficial when planting mangroves. But in general, I think the biochar community would recommend placing biochar in soil - perhaps the most seriously degraded coming first. The benefit would be centuries or millennia (?) of continuing productivity improvement that it is not obvious could also occur in the oceans Have you seen any citations to similar out-year productivity (or other) benefits if biochar was deposited in the ocean? 3. I liked very much your method of directing readers to links. However for the first (Belter and Seidel, 2013), I was unsuccessful finding anything at the WIREs ste. Can you/anyone help? 4. The second citation directed us to a small part of a Keith AGU 2011 lecture was a little disappointing as the citation history ended with 2010. Can anyone update that history - and/or describe how to get something from Google or other ? 5. Most interesting to me was the first half of the same AGU lecture - a talk by Ken Caldera comparing several CDR approaches. This is the topic of my next note - as Ken's talk had relatively little to do with oceans - and I have seen so few CDR comparisons. 6. I hope next time you can write something about harvesting ocean biomass (macroalgae and other) for use on land as input for such CDR approaches as BECCS and biochar. I believe the energy and soil benefits of such a direction of biomass movement will nicely complement the potential CDR benefits of ocean biomass. Again thanks for bringing your concise marine/oceans/geoengineering survey to our attention. Ron - Original Message - From: Chris Vivian chris.viv...@cefas.co.uk To: geoengineering@googlegroups.com Sent: Monday, February 18, 2013 4:22:19 AM Subject: [geo] Brief Summary Marine Geoengineering Techniques For your information, see the attached leaflet on marine geoengineering techniques that has been submitted to the IMO as a UK information paper for the forthcoming London Convention/Protocol Scientific Groups meeting. The leaflet is also on the Cefas website at: http://www.cefas.defra.gov.uk/publications/files/20120213-Brief-Summary-Marine-Geoeng-Techs.pdf Best wishes Chris. -- You received this message because you are subscribed to the Google Groups geoengineering group. To unsubscribe from this group and stop receiving emails from it, send an email to geoengineering+unsubscr...@googlegroups.com. To post to this group, send email to geoengineering@googlegroups.com. Visit this group at http://groups.google.com/group/geoengineering?hl=en . For more options, visit https://groups.google.com/groups/opt_out . -- You received this message because you are subscribed to the Google Groups geoengineering group. To unsubscribe from this group and stop receiving emails from it, send an email to geoengineering+unsubscr...@googlegroups.com. To post to this group, send email to geoengineering@googlegroups.com. Visit this group at http://groups.google.com/group/geoengineering?hl=en. For more options, visit https://groups.google.com/groups/opt_out.
Re: [geo] SRM = bandaid, CDR = cure
As previously pointed out on this list, monsoon disruption and ocean acidification are not widely accepted as being the certainties claimed below. A On Feb 18, 2013 6:13 PM, Rau, Greg r...@llnl.gov wrote: http://www.skepticalscience.com/print.php?n=1785 No alternative to atmospheric CO2 draw-down This article suggests that the current atmospheric CO2 level is already triggering amplifying feedbacks from the Earth system and therefore, in themselves, efforts at reduction in atmospheric CO2-emission are no longer sufficient to prevent further global warming. For this reason, along with sharp reductions in carbon emissions, efforts need to be undertaken in an attempt to reduce atmospheric CO2 levels from their current level of near-400 ppm to well below 350 ppm. NASA-applied outer space-shade technology may buy time for such planetary defense effort. The scale and rate of modern climate change have been greatly underestimated. The release to date of a total of over 560 billion ton of carbon through emissions from industrial and transport sources, land clearing and fires, has raised CO2 levels from about 280 parts per million (ppm) in pre-industrial periods to 397-400 ppm and near 470 ppm CO 2-equivalent (a value which includes the CO2-equivalent effect of methane), reaching a current CO2 growth rate of about 2 ppm per yearhttp://www.globalcarbonproject.org/ *Figure 1: Part A. Mean CO2 level from ice cores, Mouna Loa observatory and marine sites; Part B (inset). Climate forcing 1880 - 2003http://pubs.giss.nasa.gov/abs/ha06510a.html. Aerosol forcing includes all aerosol effects, including indirect effects on clouds and snow albedo. GHGs include ozone (O3) and stratospheric H2O, in addition to well-mixed greenhouse gases.* *Figure 2: Relations between CO2 rise rates and mean global temperature rise rates during warming periodshttp://cci.anu.edu.au/files/download/?id=4951 *, including the Paleocene-Eocene Thermal Maximum, Oligocene, Miocene, glacial terminations, Dansgaard-Oeschger cycles and the post-1750 period. These developments are shifting the Earth's climate toward Pliocene-like (5.2 - 2.6 million years-ago; mean global temperatures of +2-3oC above pre-industrial temperatures) and possibly toward mid-Miocene-like (approximately 16 million years-ago; mean global temperatures +4oC above pre-industrial temperatureshttp://www.nature.com/ngeo/journal/v4/n7/fig_tab/ngeo1186_ft.html) conditions within a few centuries--a geological blink of an eye. The current CO2 level generates amplifying feedbacks, including the reduced capacity of warming water to absorb CO2 from the atmosphere, CO2 released from fires, droughts, loss of vegetation cover, disintegration of methane released from bogs, permafrost and methane-bearing ice particles and methane-water molecules. With CO2 atmospheric residence times in the order of thousands to tens of thousands yearshttp://www.pnas.org/content/early/2009/01/28/0812721106.abstract, protracted reduction in emissions, either flowing from human decision or due to reduced economic activity in an environmentally stressed world, may no longer be sufficient to arrest the feedbacks. Four of the large mass extinction of species events in the history of Earth (end-Devonian, Permian-Triassic, end-Triassic, K-T boundary) have been associated with rapid perturbations of the carbon, oxygen and sulphur cycles, on which the biosphere depends, at rates to which species could not adapthttp://theconversation.edu.au/is-another-mass-extinction-event-on-the-way-5397 . Since the 18th century, and in particular since about 1975, the Earth system has been shifting away from Holocene (approximately 10,000 years to the pre-industrial time) conditions, which allowed agriculture, previously hindered by instabilities in the climate and by extreme weather events. The shift is most clearly manifested by the loss of polar icehttp://www.agu.org/pubs/crossref/2011/2011GL046583.shtml. Sea level rises have been accelerating, with a total of more than 20 cm since 1880 and about 6 cm since 1990http://www.eea.europa.eu/data-and-maps/indicators/sea-level-rise-1/assessment . For temperature rise of 2.3oC, to which the climate is committed if sulphur aerosol emission discontinueshttp://pubs.giss.nasa.gov/abs/ha06510a.html (see Figure 1), sea levels would reach Pliocene-like levels of 25 meters plus or minus 12 meters, with lag effects due to ice sheet hysteresis (system inertia). With global atmospheric CO2-equivalent (a value which includes the effect of methane) above 470 ppm, just under the upper stability limit of the Antarctic ice sheethttp://www.columbia.edu/~jeh1/2008/TargetCO2_20080407.pdf, with current rate of CO2 emissions from fossil fuel combustion, cement production, land clearing and fires of ~9.7 billion ton of carbon in 2010http://www.science.org.au/natcoms/nc-ess/documents/GEsymposium.pdf, global
[geo] CDR: Stanford weighs in
http://planetsave.com/2013/02/18/stanford-scientists-aim-to-remove-co2-from-atmosphere/ Stanford Scientists Aim To Remove CO2 From Atmosphere Joshua S Hill [http://c1planetsavecom.wpengine.netdna-cdn.com/wp-content/plugins/repostus/repostus_bttn_lng_repost.png] Turn the clock back a decade and we had all sorts of grand plans for reducing our greenhouse gas emissions levels, hoping that by 2020 we would be on the path to saving our planet. [Reducing Carbon Means Destroying Carbon]http://c1planetsavecom.wpengine.netdna-cdn.com/files/2013/02/750px-Cwall99_lg.jpg Image Credit: Wikimediahttp://en.wikipedia.org/wiki/File:Cwall99_lg.jpg Welcome to 2013 and … not so much. Unsurprisingly, scientists at Stanford University have recently come out and said that curbing our CO2 emissions may simply not be enough any more. Instead of simply hoping the long-tail of emissions reductions do something, they believe we need to start looking at carbon-negative technologies that actively remove carbon dioxide from the atmosphere. “To achieve the targeted cuts, we would need a scenario where, by the middle of the century, the global economy is transitioning from net positive to net negative CO2 emissions,” said report co-author Chris Field, a professor of biology and of environmental Earth system science at Stanford. “We need to start thinking about how to implement a negative-emissions energy strategy on a global scale.” The Stanford scientists findings are summarised in a report by Stanford’s Global Climate and Energy Project (GCEP), which describe a suite of emerging carbon-negative solutions to global warming. BECCS “Net negative emissions can be achieved when more greenhouse gases are sequestered than are released into the atmosphere,” explained Milne, an energy assessment analyst at GCEP. “One of the most promising net-negative technologies is BECCS, or bioenergy with carbon capture and storage.” For example, a BECCS system could convert woody biomass, grass, and other vegetation into electricity, chemical products, or fuels such as ethanol, leaving the CO2 emissions released during the process to be captured and stored. Estimates show that by 2050 BECCS technologies could sequester 10 billion metric tonnes of industrial CO2 emissions from installations like power plants, paper mills, ethanol processors, and other manufacturing facilities. But we have a ways to go before we are technologically able to manage this. Biochar Biochar is a plant byproduct similar to charcoal that is made from lumber waste, dried corn stalks, and other plant residues. A process called pyrolysis — which heats the vegetation slowly without oxygen — produces carbon rich chunks of biochar that can be placed in the soil as a fertiliser, which locks the CO2 underground instead of letting the CO2 re-enter the atmosphere as the plant decomposes as it naturally would. EHowever, long-term sequestration “would require high biochar stability,” they wrote. “Estimates of biochar half‐life vary greatly from 10 years to more than 100 years. The type of feedstock also contributes to stability, with wood being more stable than grasses and manure.” Net-negative Farming Another option included in the GCEP report is the idea of net-negative farming. The authors cited research done by Jose Moreira of the University of Sao Paulo who found that from 1975 to 2007, ethanol production from sugar cane in Brazil resulted in a net-negative capture of 1.5 metric tons of CO2 per cubic meter of ethanol produced. “In this model, the system took 18 years to recoup carbon emissions, with most reductions coming from soil replenishment from root growth and replacement of gasoline with ethanol,” the GCEP authors wrote. However, questions remain about the long-term effects of ethanol combustion on climate. Other Options The report also explored other options, such as sequestering carbon in the ocean, specifically the problem of ocean acidification. Currently, the more CO2 the oceans absorb the more acidic they become, resulting in algae blooms often seen in locations throughout Asia as well as the Gulf of Mexico in the US. However, research by David Keith of Harvard University suggests that adding magnesium carbonate and other minerals to the ocean to reduce acidity would also sequester atmospheric CO2 in absorbed in seawater. For more information on these options, check out the full report herehttp://gcep.stanford.edu/events/workshops_negemissions2012.html. -- You received this message because you are subscribed to the Google Groups geoengineering group. To unsubscribe from this group and stop receiving emails from it, send an email to geoengineering+unsubscr...@googlegroups.com. To post to this group, send email to geoengineering@googlegroups.com. Visit this group at http://groups.google.com/group/geoengineering?hl=en. For more options, visit https://groups.google.com/groups/opt_out.
Re: [geo] Brief Summary Marine Geoengineering Techniques
List (cc Ken) 1. This note is to draw attention to a nice April 2011 comparison of different CDR approaches that I had not seen before being sent to it by Chris Vivian.(see below). For about 25 minutes of Ken Caldeira comparing most of the CDR alternatives at an American Meteorological Society meeting, see http://www.youtube.com/watch?v=KbNDG2xFOVg 2. Quicker is to view only Ken's roughly 25 slides at: http://www.ametsoc.org/atmospolicy/climatebriefing/Caldeira.pdf 3. Here is Ken's final slide, after 1 slide each on most CDR options, broken into 3 subgroupings Main conclusions • Avoiding carbon dioxide emissions is key to reducing climate risk and damage • Carbon Dioxide Removal removes cause of climate change and ocean acidification • There are many approaches to remove carbon dioxide from the atmosphere • No approach is obviously both cheap and scalable • Best introduce no new kinds of risks • May be opportunities for some low-cost mitigation • Some could be deployed today or soon • Many are understudied 4. I would have mostly agreed two years ago, and still of course do agree with the three main bullets. But now I would modify Ken's last five sub-bullets (speaking only for biochar) as follows (and hoping other CDR practitioners will similarly append) • No approach is obviously both cheap and scalable, but biochar could/might be both - because of energy and on-going soil benefits, as well as CDR benefits • Best introduce no new kinds of risks, and biochar is in the best category - no major unavoidable risks have yet been ident ified in any peer-reviewed publication • May be opportunities for some low-cost mitigation , especially since biochar can be coupled with afforestation/refores tation - and costs must be in comparison to other options • Some could be deployed today or soon, with afforestation and biochar especially - as much is happening today even w ithout carbon credits - on every continent. • Many are understudied, but biochar is rapidly overcoming that hurdle - in many countries , through dozens of national and sub-national interest groups, and more than 100 University degree programs. 5. Ken also showed a ranking slide from the Royal Society report - where biochar got mostly a 2 out of possible high of 5. I believe most active biochar researchers today would give about a 4 on the four ranking categories. As near as I can tell, there was no biochar researcher in the expert group doing the rankings. I would like to see a new 2013 ranking, with a balanced panel. 6. This is not to say that Ken was in error on anything in his 2011 presentation. It is just that CDR needs more discussion - especially on scenarios with the large (urgency-driven) scales that are becoming more common. For new information on biochar costs and market readiness, not available two years ago, I hope Ken and others will look at these websites: www.coolplanetbiofuels.com and www.biochar-international.org Ron - Original Message - From: rongretlar...@comcast.net To: Chris Vivian chris.viv...@cefas.co.uk Cc: geoengineering@googlegroups.com Sent: Monday, February 18, 2013 1:27:24 PM Subject: Re: [geo] Brief Summary Marine Geoengineering Techniques Chris and list: snip 5. Most interesting to me was the first half of the same AGU lecture - a talk by Ken Caldera comparing several CDR approaches. This is the topic of my next note - as Ken's talk had relatively little to do with oceans - and I have seen so few CDR comparisons. -- You received this message because you are subscribed to the Google Groups geoengineering group. To unsubscribe from this group and stop receiving emails from it, send an email to geoengineering+unsubscr...@googlegroups.com. To post to this group, send email to geoengineering@googlegroups.com. Visit this group at http://groups.google.com/group/geoengineering?hl=en. For more options, visit https://groups.google.com/groups/opt_out.
[geo] Brief Summary Marine Geoengineering Techniques - MVB points
Hello Chris et al. I think this is a very interesting paper. With respect to Marine Cloud Brightening (MCB), outlined therein, I would like to add a couple of points:- If MCB is found to function as assumed in our modeling studies – which remains to be determined – it could possibly:- (1) inhibit or prohibit further coral reef damage by cooling ocean surface waters in selected areas – as with the hurricane weakening possibility mentioned in the article. (2) maintain sea-ice cover at around current values, at least up to the CO2-doubling point. Best Wishes, John lat...@ucar.edu Papers relevant to the above points are listed below:- Philip J Rasch, John Latham Chih-Chieh (Jack) Chen, Geoengineering by cloud seeding: influence on sea ice and climate system. Environ. Res. Lett. 4 (2009) 045112 (8pp) doi:10.1088/1748-9326/4/4/045112 John Latham, Keith Bower, Tom Choularton, Hugh Coe, Paul Connolly, Gary Cooper,Tim Craft, Jack Foster, Alan Gadian, Lee Galbraith, Hector Iacovides, David Johnston, Brian Launder, Brian Leslie, John Meyer, Armand Neukermans, Bob Ormond, Ben Parkes, Philip Rasch, John Rush, Stephen Salter, Tom Stevenson, Hailong Wang, Qin Wang Rob Wood, 2012, Marine Cloud Brightening, Phil.Trans.Roy. Soc. A . 2012, 370, 4217-4262. doi: 10.1098/rsta.2012.0086 Ben Parkes, Alan Gadian John Latham, 2012. Investigation into the effects of Geoengineering on Seasonal Polar Temperatures and the Meridional Heat Flux. ISRN Geophysics. Volume 2012 (2012), Article ID 142872, doi:10.5402/2012/142872 John Latham, Ben Parkes, Alan Gadian,Stephen Salter, 2012. Weakening of Hurricanes via Marine Cloud Brightening (MCB), Atmospheric Science Letters, DOI: 10.1002/asl.402 John Latham Address: P.O. Box 3000,MMM,NCAR,Boulder,CO 80307-3000 Email: lat...@ucar.edu or john.latha...@manchester.ac.uk Tel: (US-Work) 303-497-8182 or (US-Home) 303-444-2429 or (US-Cell) 303-882-0724 or (UK) 01928-730-002 http://www.mmm.ucar.edu/people/latham From: geoengineering@googlegroups.com [geoengineering@googlegroups.com] on behalf of Chris Vivian [chris.viv...@cefas.co.uk] Sent: 18 February 2013 11:22 To: geoengineering@googlegroups.com Subject: [geo] Brief Summary Marine Geoengineering Techniques For your information, see the attached leaflet on marine geoengineering techniques that has been submitted to the IMO as a UK information paper for the forthcoming London Convention/Protocol Scientific Groups meeting. The leaflet is also on the Cefas website at: http://www.cefas.defra.gov.uk/publications/files/20120213-Brief-Summary-Marine-Geoeng-Techs.pdf Best wishes Chris. -- You received this message because you are subscribed to the Google Groups geoengineering group. To unsubscribe from this group and stop receiving emails from it, send an email to geoengineering+unsubscr...@googlegroups.com. To post to this group, send email to geoengineering@googlegroups.com. Visit this group at http://groups.google.com/group/geoengineering?hl=en. For more options, visit https://groups.google.com/groups/opt_out. -- You received this message because you are subscribed to the Google Groups geoengineering group. To unsubscribe from this group and stop receiving emails from it, send an email to geoengineering+unsubscr...@googlegroups.com. To post to this group, send email to geoengineering@googlegroups.com. Visit this group at http://groups.google.com/group/geoengineering?hl=en. For more options, visit https://groups.google.com/groups/opt_out.
Re: [geo] CDR: Stanford weighs in
It is frankly somewhat amazing that this review contains no mention at all of what appears to be the single lowest cost and lowest impact way of removing excess CO2 from the atmosphere, namely the accelerated weathering of magnesium silicate bearing rock by spreading the pulverised rock at land and littoral zones. Given that this system is now quite widely published, such ignorance is surely deliberate. How is it to be explained? Oliver. On 18/02/2013 23:31, Rau, Greg wrote: http://planetsave.com/2013/02/18/stanford-scientists-aim-to-remove-co2-from-atmosphere/ Stanford Scientists Aim To Remove CO2 From Atmosphere Joshua S Hill * * Turn the clock back a decade and we had all sorts of grand plans for reducing our greenhouse gas emissions levels, hoping that by 2020 we would be on the path to saving our planet. Reducing Carbon Means Destroying Carbon http://c1planetsavecom.wpengine.netdna-cdn.com/files/2013/02/750px-Cwall99_lg.jpg Image Credit: Wikimedia http://en.wikipedia.org/wiki/File:Cwall99_lg.jpg Welcome to 2013 and … not so much. Unsurprisingly, scientists at Stanford University have recently come out and said that curbing our CO2 emissions may simply not be enough any more. Instead of simply hoping the long-tail of emissions reductions do /something/, they believe we need to start looking at carbon-negative technologies that actively remove carbon dioxide from the atmosphere. “To achieve the targeted cuts, we would need a scenario where, by the middle of the century, the global economy is transitioning from net positive to net negative CO2 emissions,” said report co-author Chris Field, a professor of biology and of environmental Earth system science at Stanford. “We need to start thinking about how to implement a negative-emissions energy strategy on a global scale.” The Stanford scientists findings are summarised in a report by Stanford’s Global Climate and Energy Project (GCEP), which describe a suite of emerging carbon-negative solutions to global warming. BECCS “Net negative emissions can be achieved when more greenhouse gases are sequestered than are released into the atmosphere,” explained Milne, an energy assessment analyst at GCEP. “One of the most promising net-negative technologies is BECCS, or bioenergy with carbon capture and storage.” For example, a BECCS system could convert woody biomass, grass, and other vegetation into electricity, chemical products, or fuels such as ethanol, leaving the CO2 emissions released during the process to be captured and stored. Estimates show that by 2050 BECCS technologies could sequester 10 billion metric tonnes of industrial CO2 emissions from installations like power plants, paper mills, ethanol processors, and other manufacturing facilities. But we have a ways to go before we are technologically able to manage this. Biochar Biochar is a plant byproduct similar to charcoal that is made from lumber waste, dried corn stalks, and other plant residues. A process called pyrolysis — which heats the vegetation slowly without oxygen — produces carbon rich chunks of biochar that can be placed in the soil as a fertiliser, which locks the CO2 underground instead of letting the CO2 re-enter the atmosphere as the plant decomposes as it naturally would. EHowever, long-term sequestration “would require high biochar stability,” they wrote. “Estimates of biochar half‐life vary greatly from 10 years to more than 100 years. The type of feedstock also contributes to stability, with wood being more stable than grasses and manure.” Net-negative Farming Another option included in the GCEP report is the idea of net-negative farming. The authors cited research done by Jose Moreira of the University of Sao Paulo who found that from 1975 to 2007, ethanol production from sugar cane in Brazil resulted in a net-negative capture of 1.5 metric tons of CO2 per cubic meter of ethanol produced. “In this model, the system took 18 years to recoup carbon emissions, with most reductions coming from soil replenishment from root growth and replacement of gasoline with ethanol,” the GCEP authors wrote. However, questions remain about the long-term effects of ethanol combustion on climate. Other Options The report also explored other options, such as sequestering carbon in the ocean, specifically the problem of ocean acidification. Currently, the more CO2 the oceans absorb the more acidic they become, resulting in algae blooms often seen in locations throughout Asia as well as the Gulf of Mexico in the US. However, research by David Keith of Harvard University suggests that adding magnesium carbonate and other minerals to the ocean to reduce acidity would also sequester atmospheric CO2 in absorbed in seawater. For more information on these options, check out the full report here http://gcep.stanford.edu/events/workshops_negemissions2012.html. * * -- You received
