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Target Atmospheric CO2: Where Should Humanity Aim?
Target Atmospheric CO2: Where Should Humanity Aim?
James Hansen, Makiko Sato, Pushker Kharecha, David Beerling, Valerie Masson-Delmotte, Mark Pagani, Maureen Raymo, Dana L. Royer, James C. Zachos Paleoclimate data show that climate sensitivity is ~3°C for doubled CO2, including only fast feedback processes. Equilibrium sensitivity, including slower surface albedo feedbacks, is ~6°C for doubled CO2 for the range of climate states between glacial conditions and icefree Antarctica. Decreasing CO2 was the main cause of a cooling trend that began 50 million years ago, large scale glaciation occurring when CO2 fell to 425±75 ppm, a level that will be exceeded within decades, barring prompt policy changes. If humanity wishes to preserve a planet similar to that on which civilization developed and to which life on Earth is adapted, paleoclimate evidence and ongoing climate change suggest that CO2 will need to be reduced from its current 385 ppm to at most 350 ppm. The largest uncertainty in the target arises from possible changes of non-CO2 forcings. An initial 350 ppm CO2 target may be achievable by phasing out coal use except where CO2 is captured and adopting agricultural and forestry practices that sequester carbon. If the present overshoot of this target CO2 is not brief, there is a possibility of seeding irreversible catastrophic effects. Please see: http://arxiv.org/pdf/0804.1126 For supporting materal see: http://arxiv.org/pdf/0804.1135 For an article in the popular press, please see: http://www.guardian.co.uk/environmen...arbonemissions |
Target Atmospheric CO2: Where Should Humanity Aim?
On Apr 15, 9:57 am, Roger Coppock wrote:
Target Atmospheric CO2: Where Should Humanity Aim? James Hansen, Makiko Sato, Pushker Kharecha, David Beerling, Valerie Masson-Delmotte, Mark Pagani, Maureen Raymo, Dana L. Royer, James C. Zachos Paleoclimate data show that climate sensitivity is ~3°C for doubled CO2, including only fast feedback processes. Equilibrium sensitivity, including slower surface albedo feedbacks, is ~6°C for doubled CO2 for the range of climate states between glacial conditions and icefree Antarctica. Decreasing CO2 was the main cause of a cooling trend that began 50 million years ago, large scale glaciation occurring when CO2 fell to 425±75 ppm, a level that will be exceeded within decades, barring prompt policy changes. If humanity wishes to preserve a planet similar to that on which civilization developed and to which life on Earth is adapted, paleoclimate evidence and ongoing climate change suggest that CO2 will need to be reduced from its current 385 ppm to at most 350 ppm. The largest uncertainty in the target arises from possible changes of non-CO2 forcings. An initial 350 ppm CO2 target may be achievable by phasing out coal use except where CO2 is captured and adopting agricultural and forestry practices that sequester carbon. If the present overshoot of this target CO2 is not brief, there is a possibility of seeding irreversible catastrophic effects. Please see: http://arxiv.org/pdf/0804.1126 For supporting materal see: http://arxiv.org/pdf/0804.1135 For an article in the popular press, please see: http://www.guardian.co.uk/environmen...techange.carbo... But the Earth is showing signs of Cooling whilst Fossil CO2 is going through the roof . |
Target Atmospheric CO2: Where Should Humanity Aim?
On Apr 15, 10:57*am, Roger Coppock wrote:
Target Atmospheric CO2: Where Should Humanity Aim? James Hansen, Makiko Sato, Pushker Kharecha, David Beerling, Valerie Masson-Delmotte, Mark Pagani, Maureen Raymo, Dana L. Royer, James C. Zachos Paleoclimate data show that climate sensitivity is ~3°C for doubled CO2, including only fast feedback processes. Equilibrium sensitivity, including slower surface albedo feedbacks, is ~6°C for doubled CO2 for the range of climate states between glacial conditions and icefree Antarctica. Decreasing CO2 was the main cause of a cooling trend that began 50 million years ago, large scale glaciation occurring when CO2 fell to 425±75 ppm, a level that will be exceeded within decades, barring prompt policy changes. If humanity wishes to preserve a planet similar to that on which civilization developed and to which life on Earth is adapted, paleoclimate evidence and ongoing climate change suggest that CO2 will need to be reduced from its current 385 ppm to at most 350 ppm. The largest uncertainty in the target arises from possible changes of non-CO2 forcings. An initial 350 ppm CO2 target may be achievable by phasing out coal use except where CO2 is captured and adopting agricultural and forestry practices that sequester carbon. If the present overshoot of this target CO2 is not brief, there is a possibility of seeding irreversible catastrophic effects. Please see: http://arxiv.org/pdf/0804.1126 For supporting materal see: http://arxiv.org/pdf/0804.1135 For an article in the popular press, please see: http://www.guardian.co.uk/environmen...techange.carbo... 500 to 2000 seems pretty OK since this is what it has been since the Jurassic (when modern animals and plants evolved) |
Target Atmospheric CO2: Where Should Humanity Aim?
On Apr 15, 8:55*pm, matt_sykes wrote:
On Apr 15, 10:57*am, Roger Coppock wrote: Target Atmospheric CO2: Where Should Humanity Aim? James Hansen, Makiko Sato, Pushker Kharecha, David Beerling, Valerie Masson-Delmotte, Mark Pagani, Maureen Raymo, Dana L. Royer, James C. Zachos Paleoclimate data show that climate sensitivity is ~3°C for doubled CO2, including only fast feedback processes. Equilibrium sensitivity, including slower surface albedo feedbacks, is ~6°C for doubled CO2 for the range of climate states between glacial conditions and icefree Antarctica. Decreasing CO2 was the main cause of a cooling trend that began 50 million years ago, large scale glaciation occurring when CO2 fell to 425±75 ppm, a level that will be exceeded within decades, barring prompt policy changes. If humanity wishes to preserve a planet similar to that on which civilization developed and to which life on Earth is adapted, paleoclimate evidence and ongoing climate change suggest that CO2 will need to be reduced from its current 385 ppm to at most 350 ppm. The largest uncertainty in the target arises from possible changes of non-CO2 forcings. An initial 350 ppm CO2 target may be achievable by phasing out coal use except where CO2 is captured and adopting agricultural and forestry practices that sequester carbon. If the present overshoot of this target CO2 is not brief, there is a possibility of seeding irreversible catastrophic effects. Please see: http://arxiv.org/pdf/0804.1126 For supporting materal see: http://arxiv.org/pdf/0804.1135 For an article in the popular press, please see: http://www.guardian.co.uk/environmen...techange.carbo... 500 to 2000 seems pretty OK since this is what it has been since the Jurassic *(when modern animals and plants evolved)- Nah ah ... Toxic levels of carbon dioxide: According to occupational exposure and controlled atmosphere research into CO2 toxicology, CO2 is hazardous via direct toxicity at levels above 5%, concentrations not encountered in nature [except perhaps at or near an active volcano or at water- logged soils]. At these high levels there is risk of death from carbon dioxide poisoning. At lower levels there may health effects and there certainly are complaints of exposure at lower levels. In the preceding section of this article, at CO2 POISONING SYMPTOMS we discussed symptoms of carbon dioxide exposure. On specific individuals, the effects of exposure to elevated levels of carbon dioxide (CO2) vary by individual and with exposure level, and exposure duration, ranging from drowsiness (perhaps at levels over 1000 ppm continuous exposure) to the toxic effects listed just above. ... The U.S. EPA CO2 exposure limits: The U.S. EPA recommends a maximum concentration of Carbon dioxide CO2 of 1000 ppm (0.1%) for continuous exposure. ASHRAE standard 62-1989 recommends an indoor air ventilation standard of 20 cfm per person of outdoor air or a CO2 level which is below 1000ppm. http://www.inspect-ny.com/hazmat/CO2gashaz.htm |
Target Atmospheric CO2: Where Should Humanity Aim?
On Apr 15, 2:44*pm, Fran wrote:
On Apr 15, 8:55*pm, matt_sykes wrote: On Apr 15, 10:57*am, Roger Coppock wrote: Target Atmospheric CO2: Where Should Humanity Aim? James Hansen, Makiko Sato, Pushker Kharecha, David Beerling, Valerie Masson-Delmotte, Mark Pagani, Maureen Raymo, Dana L. Royer, James C. Zachos Paleoclimate data show that climate sensitivity is ~3°C for doubled CO2, including only fast feedback processes. Equilibrium sensitivity, including slower surface albedo feedbacks, is ~6°C for doubled CO2 for the range of climate states between glacial conditions and icefree Antarctica. Decreasing CO2 was the main cause of a cooling trend that began 50 million years ago, large scale glaciation occurring when CO2 fell to 425±75 ppm, a level that will be exceeded within decades, barring prompt policy changes. If humanity wishes to preserve a planet similar to that on which civilization developed and to which life on Earth is adapted, paleoclimate evidence and ongoing climate change suggest that CO2 will need to be reduced from its current 385 ppm to at most 350 ppm. The largest uncertainty in the target arises from possible changes of non-CO2 forcings. An initial 350 ppm CO2 target may be achievable by phasing out coal use except where CO2 is captured and adopting agricultural and forestry practices that sequester carbon. If the present overshoot of this target CO2 is not brief, there is a possibility of seeding irreversible catastrophic effects. Please see: http://arxiv.org/pdf/0804.1126 For supporting materal see: http://arxiv.org/pdf/0804.1135 For an article in the popular press, please see: http://www.guardian.co.uk/environmen...techange.carbo.... 500 to 2000 seems pretty OK since this is what it has been since the Jurassic *(when modern animals and plants evolved)- Nah ah ... Toxic levels of carbon dioxide: According to occupational exposure and controlled atmosphere research into CO2 toxicology, CO2 is hazardous via direct toxicity at levels above 5%, concentrations not encountered in nature [except perhaps at or near an active volcano or at water- logged soils]. At these high levels there is risk of death from carbon dioxide poisoning. At lower levels there may health effects and there certainly are complaints of exposure at lower levels. In the preceding section of this article, at CO2 POISONING SYMPTOMS we discussed symptoms of carbon dioxide exposure. On specific individuals, the effects of exposure to elevated levels of carbon dioxide (CO2) vary by individual and with exposure level, and exposure duration, ranging from drowsiness (perhaps at levels over 1000 ppm continuous exposure) to the toxic effects listed just above. ... The U.S. EPA CO2 exposure limits: The U.S. EPA recommends a maximum concentration of Carbon dioxide CO2 of 1000 ppm (0.1%) for continuous exposure. ASHRAE standard 62-1989 recommends an indoor air ventilation standard of 20 cfm per person of outdoor air or a CO2 level which is below 1000ppm. http://www.inspect-ny.com/hazmat/CO2gashaz.htm- Hide quoted text - - Show quoted text - Agricultural workers in greenhouses work with CO2 generally at 5000 ppm as a maximum recomended level so your 1000 is from some other source, perhaps for ill or old people in hospital? Anyway, it is unlikely we will ever get to 1000 since plant growth will explode. |
Target Atmospheric CO2: Where Should Humanity Aim?
chemist wrote:
On Apr 15, 9:57 am, Roger Coppock wrote: Target Atmospheric CO2: Where Should Humanity Aim? James Hansen, Makiko Sato, Pushker Kharecha, David Beerling, Valerie Masson-Delmotte, Mark Pagani, Maureen Raymo, Dana L. Royer, James C. Zachos Paleoclimate data show that climate sensitivity is ~3°C for doubled CO2, including only fast feedback processes. Equilibrium sensitivity, including slower surface albedo feedbacks, is ~6°C for doubled CO2 for the range of climate states between glacial conditions and icefree Antarctica. Decreasing CO2 was the main cause of a cooling trend that began 50 million years ago, large scale glaciation occurring when CO2 fell to 425±75 ppm, a level that will be exceeded within decades, barring prompt policy changes. If humanity wishes to preserve a planet similar to that on which civilization developed and to which life on Earth is adapted, paleoclimate evidence and ongoing climate change suggest that CO2 will need to be reduced from its current 385 ppm to at most 350 ppm. The largest uncertainty in the target arises from possible changes of non-CO2 forcings. An initial 350 ppm CO2 target may be achievable by phasing out coal use except where CO2 is captured and adopting agricultural and forestry practices that sequester carbon. If the present overshoot of this target CO2 is not brief, there is a possibility of seeding irreversible catastrophic effects. Please see: http://arxiv.org/pdf/0804.1126 For supporting materal see: http://arxiv.org/pdf/0804.1135 For an article in the popular press, please see: http://www.guardian.co.uk/environmen...techange.carbo... But the Earth is showing signs of Cooling whilst Fossil CO2 is going through the roof . Welcome to La Nina, lying idiot. |
Target Atmospheric CO2: Where Should Humanity Aim?
matt_sykes wrote:
On Apr 15, 2:44 pm, Fran wrote: On Apr 15, 8:55 pm, matt_sykes wrote: On Apr 15, 10:57 am, Roger Coppock wrote: Target Atmospheric CO2: Where Should Humanity Aim? James Hansen, Makiko Sato, Pushker Kharecha, David Beerling, Valerie Masson-Delmotte, Mark Pagani, Maureen Raymo, Dana L. Royer, James C. Zachos Paleoclimate data show that climate sensitivity is ~3°C for doubled CO2, including only fast feedback processes. Equilibrium sensitivity, including slower surface albedo feedbacks, is ~6°C for doubled CO2 for the range of climate states between glacial conditions and icefree Antarctica. Decreasing CO2 was the main cause of a cooling trend that began 50 million years ago, large scale glaciation occurring when CO2 fell to 425±75 ppm, a level that will be exceeded within decades, barring prompt policy changes. If humanity wishes to preserve a planet similar to that on which civilization developed and to which life on Earth is adapted, paleoclimate evidence and ongoing climate change suggest that CO2 will need to be reduced from its current 385 ppm to at most 350 ppm. The largest uncertainty in the target arises from possible changes of non-CO2 forcings. An initial 350 ppm CO2 target may be achievable by phasing out coal use except where CO2 is captured and adopting agricultural and forestry practices that sequester carbon. If the present overshoot of this target CO2 is not brief, there is a possibility of seeding irreversible catastrophic effects. Please see: http://arxiv.org/pdf/0804.1126 For supporting materal see: http://arxiv.org/pdf/0804.1135 For an article in the popular press, please see: http://www.guardian.co.uk/environmen...techange.carbo... 500 to 2000 seems pretty OK since this is what it has been since the Jurassic (when modern animals and plants evolved)- Nah ah ... Toxic levels of carbon dioxide: According to occupational exposure and controlled atmosphere research into CO2 toxicology, CO2 is hazardous via direct toxicity at levels above 5%, concentrations not encountered in nature [except perhaps at or near an active volcano or at water- logged soils]. At these high levels there is risk of death from carbon dioxide poisoning. At lower levels there may health effects and there certainly are complaints of exposure at lower levels. In the preceding section of this article, at CO2 POISONING SYMPTOMS we discussed symptoms of carbon dioxide exposure. On specific individuals, the effects of exposure to elevated levels of carbon dioxide (CO2) vary by individual and with exposure level, and exposure duration, ranging from drowsiness (perhaps at levels over 1000 ppm continuous exposure) to the toxic effects listed just above. ... The U.S. EPA CO2 exposure limits: The U.S. EPA recommends a maximum concentration of Carbon dioxide CO2 of 1000 ppm (0.1%) for continuous exposure. ASHRAE standard 62-1989 recommends an indoor air ventilation standard of 20 cfm per person of outdoor air or a CO2 level which is below 1000ppm. http://www.inspect-ny.com/hazmat/CO2gashaz.htm- Hide quoted text - - Show quoted text - Agricultural workers in greenhouses work with CO2 generally at 5000 ppm as a maximum recomended level ..for an 8 hour day. so your 1000 is from some other source, perhaps for ill or old people in hospital? Nope, see 'continuous exposure'. Anyway, it is unlikely we will ever get to 1000 since plant growth will explode. Which doesn't change the fact that once again, Matt Sykes has been caught lying outright. |
Target Atmospheric CO2: Where Should Humanity Aim?
On Apr 15, 1:57*am, Roger Coppock wrote:
Target Atmospheric CO2: Where Should Humanity Aim? James Hansen, Makiko Sato, Pushker Kharecha, David Beerling, Valerie Masson-Delmotte, Mark Pagani, Maureen Raymo, Dana L. Royer, James C. Zachos Paleoclimate data show that climate sensitivity is ~3°C for doubled CO2, Ludicrous speculation. No such data exists. These AGW whackjobs can't distintinguish between data and their overactive imaginations. including only fast feedback processes. Equilibrium sensitivity, including slower surface albedo feedbacks, is ~6°C for doubled CO2 for the range of climate states between glacial conditions and icefree Antarctica. Decreasing CO2 was the main cause of a cooling trend that began 50 million years ago, Plainly false. large scale glaciation occurring when CO2 fell to 425±75 ppm, a level that will be exceeded within decades, barring prompt policy changes. If humanity wishes to preserve a planet similar to that on which civilization developed and to which life on Earth is adapted, paleoclimate evidence and ongoing climate change suggest that CO2 will need to be reduced from its current 385 ppm to at most 350 ppm. The largest uncertainty in the target arises from possible changes of non-CO2 forcings. An initial 350 ppm CO2 target may be achievable by phasing out coal use except where CO2 is captured and adopting agricultural and forestry practices that sequester carbon. If the present overshoot of this target CO2 is not brief, there is a possibility of seeding irreversible catastrophic effects. It's unfortunate you cannot provide us links to your imagination. Please see: http://arxiv.org/pdf/0804.1126 For supporting materal see: http://arxiv.org/pdf/0804.1135 For an article in the popular press, please see: http://www.guardian.co.uk/environmen...techange.carbo... |
Target Atmospheric CO2: Where Should Humanity Aim?
On Apr 15, 7:00*am, matt_sykes wrote:
[ . . . ][ Agricultural workers in greenhouses work with CO2 generally at 5000 ppm as a maximum recomended level so your 1000 is from some other source, perhaps for ill or old people in hospital? In San Diego two greenhouse workers died from CO2. Port workers packing stuff in dry ice also died. Now, CalOSHA keeps a close watch on CO2 concentrations at workplaces. Anyway, it is unlikely we will ever get to 1000 since plant growth will explode. How tragic! You actually expect a miracle that will save us from our greenhouse gas emissions. |
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