Hansen et al concludes “the rate of sea level rise is likely to accelerate during the next several years.”

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"Hansen et al concludes “the rate of sea level rise is likely to accelerate during the next several years.”"

Humanity’s “Faustian aerosol bargain”

James Hansen has posted a new 52-page draft paper entitled “Earth’s Energy Imbalance and Implications.”

While this paper is a tougher read than most, the good news is that Hansen gave an hour-long talk on this topic last week, which is posted to YouTube:

The video makes it clearer than the article that Hansen is kidding about his grandchildren, Sophie and Connor — though not about the implications of his analysis about the “net forcing”:

Global warming has been limited, as aerosol cooling partially offsets GHG warming. But aerosols remain airborne only several days, so they must be pumped into the air faster and faster to keep pace with increasing long-lived GHGs. However, concern about health effects of particulate air pollution is likely to lead to eventual reduction of human-made aerosols. Thereupon the Faustian payment will come due.

If Sophie’s +2 W/m2 is close to the truth (aerosol forcing -1 W/m2), even a major effort to clean up aerosols, say reduction by half, increases the net human-made forcing only 25 percent. But Connor’s aerosol forcing (-2 W/m2) means that reduction of aerosols by half would double the net climate forcing. Given global climate effects already being observed (IPCC, 2007), a doubling of the climate forcing suggests that humanity may face a grievous Faustian payment.

Most climate models in IPCC studies use aerosol forcing about -1 W/m2. We will argue that this understates the true aerosol effect.

Later he notes, “If the negative aerosol forcing is understated by as much as 0.7 W/m2, it means that aerosols have been counteracting half or more of the GHG forcing. In that event, humanity has made itself a Faustian bargain more dangerous than commonly supposed.”  Hansen has said this is a “Faustian aerosol bargain” because it can be maintained only through “continued exponential growth of the atmospheric aerosol load.”

Here is what the paper says on the “Implications for sea level”:

Based on our inferred planetary energy imbalance, we conclude that the rate of sea level rise is likely to accelerate during the next several years.    Reasons for that conclusion are as follows.

First, the contribution of thermal expansion to sea level is likely to increase above recent rates. The nearly constant rate of sea level rise since 1993 masks the fact that thermal expansion must have been less in the Argo era than in the prior decade, when ice melt was less but sea level rose 3 mm/year. Solar minimum and a diminishing Pinatubo rebound effect both contributed to a declining rate of thermal expansion during the past several years. But the Pinatubo effect is now essentially spent and solar irradiance change should now work in the opposite sense.

Second, the rate of ice melt is likely to continue to accelerate. Planetary energy imbalance now is positive, substantial, and likely to increase as greenhouse gases and solar irradiance increase. Thus, despite year-to-year fluctuations, global temperature will increase this decade and there will be a substantial flux of energy into the ocean. Increasing ocean heat content provides energy for melting sea ice and ice shelves. Sea ice protects the ice sheets from heating and ice shelves mechanically buttress the ice sheets. It has been argued that loss of these protections may be the most important factor causing more rapid discharge from ice sheets to the ocean (Hansen, 2005, 2007).

Indeed, the rate of ice melt is likely to continue to accelerate — see JPL bombshell: Polar ice sheet mass loss is speeding up, on pace for 1 foot sea level rise by 2050.

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31 Responses to Hansen et al concludes “the rate of sea level rise is likely to accelerate during the next several years.”

  1. Michael Tucker says:

    “…this is a “Faustian aerosol bargain” because it can be maintained only through “continued exponential growth of the atmospheric aerosol load.””

    It seems to me, and this is just an impression I have no data to back this up, but since China is intent on building a truly enormous number of coal plants (2200 new coal plants by 2030) and the House Republicans are intent on protecting America’s particulate pollution, that Faustian bargain might just hold up for a few more years. China is committed to the race for at least the next 20 years and they have a wonderful supply of air pollution and yearly dust storms from Mongolia to keep the atmosphere loaded.

  2. Tom says:

    i can’t get over how ignorant we are as a species. We’ll be extinct within 100 yrs.

  3. Richard Brenne says:

    Michael Tucker (#1, always) – That’s a good point.

    At the bottom of the 3rd paragraph on page 3 of Hansen’s paper he writes: “However, concern about health effects of particulate air pollution is likely to lead to eventual reduction of human-made aerosols. Thereupon the Faustian payment will come due.”

    If I were writing or editing this paper (which I’m clearly not), I might rework that sentence to something like: “Humanity is on a treadmill where our air pollution aerosols might be reducing our greenhouse gas emission warming effects by around half, possibly more. If humanity manifest any common sense about the health effects on humans and all plants of such aerosols, they would curtail them immediately. This combined with the minimum solar activity in the reliable record since satellite data began in 1979 during the last six years or so naturally increasing could compound the effects of human greenhouse gas emissions into sudden warming unlike any civilization has seen. Also, a severe economic downturn could lead to a loss of capital and the ability to maintain the current fossil fuel-based global economy, meaning those emissions could be curtailed involuntarily. And since fossil fuels are necessarily limited, eventually there has to be a decline in their use, although over a century of more the lack of conventional oil could mean the burning of more coal for electricity and also coal to liquids, as well as the burning of more tar sands and eventually oil shale as well. Also the decline in conventional fossil fuels could mean far more burning of biomass to compensate for the loss of home heating oil and natural gas and electricity for heating, cooking and all other appliances. Just as humanity appears to perpetually want to double down with the devil, biomass burning is a double whammy because of the added CO2 and loss of the carbon sink trees provide. Enough of this activity over a long enough period could create a runaway greenhouse effect like the one experienced on Venus, and even a tiny fraction of this event could create a dead planet, and our own could be one of the earlier species lost in this process. But ultimately concern about health effects, enough economic downturn or the loss of the primary fuels we burn could create a spike in global average temperature unlike any we’ve seen. Either way, to quote the eloquence of David Letterman, we’re screwed.”

  4. Turboblocke says:

    MT @ #1: Where does the figure of 2200 coal plants in China come from?

  5. Esko Pettay says:

    We have studied this issue in great detail and believe that shipping plays a big role. Ocean-going freight ships burn heavy fuel oil (bunker oil) that contains, as a global average, about 2.7 per cent sulphur. This is 15-20 per cent of the humanity’s total sulphur emissions. Aerosol researchers have calculated, that the sulphur spread by the ships over the oceans provides between 17 and 39 per cent of total cooling impact of anthropogenic aerosol emissions. According to an often quoted calculation, by Ernst Lauer and his colleagues, the ships’ cooling impact should be about 0.58 W/m2 in 2012. However, if the planned sulphur emission cuts (by international maritime organization IMO) were carried out, the cooling impact would be reduced to 0.27 W/m2. The difference, 0.31 W/m2, should increase our planetary heat balance, or global warming by 31 – 44 per cent.

    I will post a link to our final report here in CP comments in the coming weeks after proofreading.

  6. Colorado Bob says:

    One Glacier Range Found to Contribute 10 Percent of World’s Melting Ice

    Gardner looked at more recent changes: during the years 2004 to 2009. Over that study period, he found, the glacier lost a volume equivalent to about 75 percent of Lake Erie, the majority of that loss happening between 2006 and 2009. In these years, the loss was four times what it had been in the late 1990s.

    The Canadian Arctic Archipelago includes thousands of islands covering 550,000 square miles (1.4 million square kilometers), nearly the size of Alaska. It is home to one of the largest freshwater glacier ranges on Earth, which has 3½ times the volume of the combined Great Lakes.

    http://www.livescience.com/13809-canadian-arctic-glacier-melting.html

  7. Mike # 22 says:

    Trenberth’s missing heat never made it past the clouds. No luck at all, it seems.

  8. Michael Tucker says:

    Turboblocke, you can find that here:
    http://climateprogress.org/2011/04/14/export-coal-china/#more-46807

    But it is really old news. China has not change its policy on coal plants. They desperately need all the cheap electricity they can get.

  9. Richard Brenne says:

    Michael Tucker (#8) – I would say they “desperately want” rather than “desperately need” when such needs could contribute significantly to the end of all life on Earth, as Hansen says in his recent book.

  10. Richard Brenne says:

    I was sending an e-mail to Dr. Hansen today but first I’ll post it here in open-letter form and he can respond here if he sees it and would like, as can anyone else:

    Dr. Hansen:

    After living in Boulder and attending many NCAR, NOAA, CIRES, INSTAAR and NSIDC talks and conferences, I’m now attending a series produced by the Portland USGS Office in conjunction with both Oregon State and Portland State.

    This series focuses on hydrology and speaker after speaker talks about past (often 20th century) observations and combines them with various computer models.

    While showing moments of appropriate concern, their conclusions are usually along the lines of “Climate models can’t be nearly as accurate with precipitation as they are with temperatures and so our only conclusion is that the next century of stream flows will be much like the last.”

    To me they’re making several fundamental mistakes, and I’d like to get your infinitely more-informed view about this.

    1) They’re often talking about average stream and river run-offs, and periods of more severe drought punctuated by more dramatic precipitations events could be masked in these averages by the former cancelling out the latter and vice-versa.

    2) They make linear projections and assumptions based on 20th Century data, when warming then was mild compared to what it will probably be in the next century, when it could increase by 10 times or more from the 20th Century increase of less than .8 C.

    3) When there is uncertainty, the conservative view based on obsolete data is chosen.

    4) Most hydrologists are studying one particular stream, river or watershed especially closely, and resolution down to that level is difficult.

    My guesses based on your work, Kevin Trenberth’s work and others is that the next 100 years will increasingly look less and less like the last 100.

    As Kevin and others (including Susan Solomon in her recent paper) says, since 1970 there has been around a 1 degree Fahrenheit (.6 C) increase in global average temperature, leading to 4% more water vapor in the atmosphere. That (as calculated by CP commenters) is like 1.5 Lake Superiors additional water vapor in the warmer atmosphere that both creates more evaporation and can hold more water vapor.

    The energy added to the system also since 1970 (and also calculated by CP commenters) is the equivalent to the energy output from around 190,000 nuclear power plants operating continuously, with about 10 more such power plants coming on line each day.

    The combination of these things leads to increased likelihood of record-tying (with 2005) warm years like 2010 which means an increased likelihood of record heat waves including the 19 national heat records set during 2010, when no national cold records were set. This leads to an increased likelihood of record sea surface temperatures in places like the Indian Ocean that contributed both to Western Russia’s record heat wave and Pakistan’s record flooding, which displaced 20 million people and still leaves 4 million homeless.

    Similar dramatic events occurred in Queensland, Australia, Nashville, Tennessee, Sri Lanka, China, Vietnam and many other places in 2010 alone.

    The conservative IPCC Report’s worst-case projection is about 10 times the warming we’ve experienced so far since 1970, so that could mean 40% additional water vapor in the atmosphere, or the equivalent to 15 Lake Superiors, with the equivalent to 1,900,000 nuclear power plants in energy added to the system.

    My guess is that that would create storms like humans can’t now imagine. It wouldn’t happen every year or even decade in a given place, but within 100 years or the design-life of most buildings and other infrastructure, most places would have unprecedented storms that damaged a high and growing percentage of all buildings.

    Only the sharpest peaks and ridges could avoid a foot or more of water rushing rapidly down most inclines at some point, with many feet in any gulley, ravine or existing creek. Most basements and first floors worldwide would be flooded at some point, and low-lying areas would likely be under a dozen or more feet during the worst events, or several meters if American’s ever come to understand the metric system.

    But these talks by engineers, geographers and hydrologists don’t include any of what I’m saying until I invariably bring it up with the first question, like Helen Thomas with an NCAR baseball cap.

    One PSU geographer speaker even said that “We’re not seeing any more extreme precipitation events” and the audience of over 100 students as well as many other scientists left the auditorium with that as their understanding.

    I look to the best experts in all fields for the best and latest understanding about anything, and your paper is another in a long line of excellent papers. Anyone who can ask for the century’s strongest volcanic eruption and then the minimum solar output on record as you have to test the accuracy of climate models must have some pretty strong connections, and is someone worth listening to.

    Thanks for considering this and I look forward to your response. You or anyone else can also e-mail me at rabrenne@hotmail.com.

  11. Michael Tucker says:

    Richard Brenne,

    It seems to me the result is the same no matter which word you select. Their ‘wants’ “…could contribute significantly to the end of all life on Earth…” as well. In any case China is moving ahead with their plans and I sure hope Dr Hansen does not attempt to disrupt any of their ground breaking ceremonies. I don’t want to see China build all the projected coal plants but I also don’t want to see Dr Hansen in a Chinese prison.

  12. Leif says:

    Esko Pettay @ 5: On the other hand don’t ships emit a large amount of black carbon which must settle out someplace. Snow fields and Polar ice caps for instance. Also, if the polar shipping lanes open, those same ships will be that much closer to the ice fields. A large ship will burn ~ a gallon of fuel to go a few hundred feet at best, translating to lots of black carbon absorbing sunlight. I would think that effect would largely negate any aerosol cooling effect. Do you have any enlightenment on that relationship? Have you only looked at the cooling side of the equation?

  13. Robert In New Orleans says:

    Don’t tell I have to start packing, I just mowed the lawn! :)

  14. Vic says:

    Near such major cities as Beijing and Shanghai, sulfur dioxide emissions remain high, but are slowly declining. One reason is that the government has shuttered hundreds of small, inefficient coal-fired plants, which had little money for technology upgrades and were difficult to regulate. Larger plants, originally built without scrubbers, have been required to retrofit facilities since the mid-2000s. And since 2007, all large state-owned factories and coal-fired power plants with SO2 scrubbers have been required to install emissions-monitoring equipment to make sure the scrubbers are in fact turned on and operating correctly.

    Between 2006 and 2010, China’s sulfur dioxide emissions decreased more than 13 percent.

    http://e360.yale.edu/feature/china_takes_first_steps_in_the_fight_against_acid_rain/2333/

    ———–

    The Ozone Monitoring Instrument (OMI) aboard NASA’s Aura satellite observed substantial increases in total column SO2 and tropospheric column NO2 from 2005 to 2007, over several areas in northern China where large coal-fired power plants were built during this period. The OMI-observed SO2/NO2 ratio is consistent with the SO2/NOx emissions estimated from a bottom-up approach. In 2008 over the same areas, OMI detected little change in NO2, suggesting steady electricity output from the power plants. However, dramatic reductions of SO2 emissions were observed by OMI at the same time. These reductions confirm the effectiveness of the flue-gas desulfurization (FGD) devices in reducing SO2 emissions, which likely became operational between 2007 and 2008. 

    http://www.agu.org/pubs/crossref/2010/2010GL042594.shtml

  15. espiritwater says:

    Richard, #3– Touche!

  16. Mulga Mumblebrain says:

    The concentration on China and its emissions seems to me a very retrograde step. The MSM in the West, as well as its ‘false balance’ between science and denialism, (taken to the extreme of outright support for denialism by the Murdoch pathocracy)its denial or ignoring of every other ecological crisis, its insistence that remedial action must be ‘market-based’ ie run by the same capitalists whose insatiable greed got us into this mess, is increasingly attempting to fix the blame on China.
    Of course this is just one front in the avalanche of Sinophobia that has been blown up in recent years as the Western, and the US in particular, ruling elites look for a ‘new enemy’ to divert the plebs’ attention from the collapse of Western economies and societies. Even more to the point the global Western ruling elites dread the day when they no longer call the shots, when they can no longer bully, intimidate, subvert, or invade any poor world country that dares to not follow orders. The Chinese are forging trade relations around the world, to which the West has replied with military entanglements, the financing of anti-Chinese political parties, the invasion of countries like Libya judged too close to China, and a relentless propaganda campaign to paint China as a menace.
    This campaign was quite marked at Copenhagen, where the Western MSM blamed China for the failure of the talks, but the media of the non-Western world and non-Western activists painted an entirely different picture. The subsequent revelation, totally ignored by the Western MSM, that the Danes had a prepared ‘agreement’ (obviously confected with other Western input), very much to the rich country’s advantage and the poor world’s detriment, ready and attempted to impose it, as has been the pattern over decades at trade ‘negotiations’ such as GATT and WTO talks, proved the point.
    The one very faint hope of salvation left for mankind requires absolute disinterested co-operation between nations in the interests of humanity as a whole. And that is precisely the type of action that the West has NEVER followed in the last 500 years, mostly because the elites who control the West see themselves as demi-gods, the highest expression of human virtue and ability, and regard non-Westerners with barely concealed contempt. I’m afraid that the next few decades will be witness to more and more Libyas, Iraqs, Afghanistans etc, as the West seeks not to change its avaricious and destructive behaviour, but, instead, falls back on its remaining strength, military violence, to shape a collapsing world to its interests.

  17. catman306 says:

    @mulga mumblebrain: Thank you for introducing a new (for me), and important word:

    Definition of Pathocracy
    Definition: pathocracy (n). A system of government created by a small pathological minority that takes control over a society of normal people

    Click the link and find 20 characteristics. It’s everywhere and it’s sick.

    http://pathocracy.wordpress.com/definition/

  18. Lewis C says:

    Hansen states:
    “If the negative aerosol forcing is understated by as much as 0.7 W/m2, it means that aerosols have been counteracting half or more of the GHG forcing. In that event, humanity has made itself a Faustian bargain more dangerous than commonly supposed.”
    And Joe comments:
    Hansen has said this is a “Faustian aerosol bargain” because it can be maintained only through “continued exponential growth of the atmospheric aerosol load.”

    The latter point is true only within bounds: if an acceptable means of Albido Restoration can be developed as an alternative, the risk of more than doubling the warming by the necessary ending of sulphate aerosols can be avoided. If that doubling were allowed to occur, it would not only massively accelerate cryosphere decline and albido loss, but also advance most other feedbacks’ CO2 & CH4 outputs.

    From this perspective the critical goal is not a peak level of CO2e ppmv – which has a three to four decade timelag before its warming potential and impacts are first realized – it is peak degrees C of anthro+feedback-driven warming. Yet as Joe has written, none of the proposals to date for a ‘stabilization’ at 2.0C or 1.5C have included the rising permafrost outputs, let alone the full range of known feedbacks. Nor are the feedbacks’ interactive evolutions readily calculable, given the chaotic and unpredictable timing and intensity of the weather events by which many are driven – meaning that current ‘degrees C’ targets must also inherently lack scientific rigour, and thus any credibility as achievable or reliable diplomatic goals.

    So can anyone explain how we are to escape the vicious dilemma of the essential rapid GHG Mitigation causing substantially increased warming due to its closure of the ‘sulphate parasol’, and thereby causing additional acceleration of the feedbacks, without the use of sufficient carefully targetted Albido Restoration to regain a 19th century global temperature ?

    [For any reader fresh to these discussions I should add that Albido Restoration and rapid GHG control are of course near-pointless without a commensurate scale of Carbon Recovery to steadily cleanse the atmosphere and so avoid eradicating the ecology of the oceans, along with its terrestrial dependents].

    Regards,

    Lewis

  19. Merrelyn Emery says:

    Catman306 #17. Thank you for that link. It is heartening to know that I am not the only person who objects violently to “Human Resources”. That the usual response I get to my objections is a blank stare accompanied by the slight but obvious body language that says “stupid old biddy” indicates how far destructive mechanistic thought has permeated every aspect of our lives, ME

  20. Peter M says:

    The role of aerosols seems to have been understated in most forecasts for warming thus far. So many people I know say- ‘I have yet to see a discernible change in climate’ or I see no ‘warming’ or ‘why all the snow and cold last winter’… If the aerosols are blocking half the warming, then we are seeing a delayed time frame on what 393ppm C02 can offer. Though the current C02 level is in the pipeline, no?

    That ‘Faustian bargain’ will not last much longer. I am no physicist, but it seems the Aerosol Parasol, thus far has limited warming, as Hansen has said- giving those in the Denier community ample slack to discredit climate scientists and climate change. As long as the Aerosols remain- the warming will be delayed. The question is; when will the CO2 overcome this aerosol in the atmosphere (as it declines in itself) and once this opaque film has been removed, what will be the end result?

  21. Esko Pettay says:

    Leif @ 12

    A recent study by James J. Corbett and his co-workers pointed out, that increased marine traffic in the Arctic Ocean could greatly accelerate the warming of this reason, if the ships emit large quantities of soot particles that land on snow and ice. So yes I’m aware of that problem.

    The basic idea would be to keep using normal high sulphur fuel in Open Ocean in lower latitudes. It would be better to use clean fuels (or scrubbers) in the northern seas (especially the Arctic) and close to shore/habitation. This way we could keep most of the cooling impact and still avoid the harmful effects (health and albedo changes on snow). Some rerouting might be needed to maximise benefits while keeping the negative impacts in minimum. It is a tricky situation. But if we really have become dependent on aerosols (as it seems) it might be a good idea to think carefully before cleaning the emissions. In a perfect world we would obviously want to get rid of all such emissions.

  22. Lewis C says:

    Peter at 21/. -
    “If the aerosols are blocking half the warming, then we are seeing a delayed time frame on what 393ppm C02 can offer. Though the current C02 level is in the pipeline, no?”

    Given the thirty to forty year timelag on the warming effect of a given level of CO2 ppmv, the 0.62C warming now seen reflects the potential of the CO2 ppmv in the mid-1970s less the current sulphate parasol effect.

    As to where we’re headed, in the absence of an effective albedo restoration effort, the following numbers may give a rough idea. – We had ~335ppmv of CO2 in ’75, which was an increase of 55 over the pre-industrial 280ppmv, and since then a further 55 has been added to give the present level of ~390ppmv.
    Thus over the next ~35 years time, say by the end of 2045, we could expect a doubling of present warming plus the increment from the sulphate parasol’s closure, assuming that full sulphate mitigation was achieved by then.

    Using the IPCC scenarios’ estimate of the sulphate parasol deflecting another 25% of the warming, the 2045 warming would then be :
    0.62C x 2 x 1.25 = 1.55C

    Using Hansen’s projection of the sulphate parasol deflecting another 100% of the warming, the 2045 warming would then be :
    0.62C x 2 x 2 = 2.48C

    However, in the absence of albedo restoration, these rough estimates may heavily understate the warming we can expect due to the accelerating cryosphere decline and resulting albedo loss. The current level of albedo loss was recently reported as already imposing a forcing equivalent to ~30% of our total CO2 emissions.

    Temperature post 2045 would reflect the global GHG output from now on, plus the rising emissions of CO2 & CH4 from diverse interactive feedbacks, plus the direct forcing due to rising albido loss.

    However, it seems increasingly obvious that albedo restoration will have to be employed just to control the warming to which we are already committed by our past pollution outputs. Failure to do so – whether through environmentalists’ continued opposition or through the lack of a reliably effective technology, would mean that even with stringent mitigation of anthro-GHG outputs the interactive feedbacks would be left to run amok, imposing increasingly uninhabitable consequences across rich and poor nations alike.

    Regards,

    Lewis

  23. Joan Savage says:

    Besides albedo and aerosols, Hansen demonstrated other forcing factors, notably including the recent low period of solar irradiance (Fig 21), as well as the successful reduction in two components of positive forcing, the reduction of CFCs and methane emissions (Fig. 20).

    The Fig. 20 is among the few encouraging graphs I’ve seen in a long time, a bit of evidence for “we can do it.”

    What is intriguing are his comments (beginning circa minute 45 in video) about what would be needed to stabilize at current climate conditions.

    With their estimate of current planetary imbalance of 0.5 to 0.6 Watt/ m2, the CO2 would have to drop to 360 ppm, but that is in the low phase of a solar cycle. At the peak of a typical active part of the solar cycle, the imbalance would be about three-quarters of a W/m2, and the compensatory level of CO2 would be 345 ppm, an even lower reduction in GHGs than for the recent years of low solar activity.

    Phasing GHG reduction policy to solar cycles is a new idea. I don’t want to take it out of context, but it is something to think about, along with the good news that getting rid of CFCs has worked.

  24. John McCormick says:

    RE # 5

    Esko,in the US Midwest, coal burning power plants are likely fired by medium and high sulfur coal. The plants are restricted via the Clean Air Ac on the amount of SO2 they emit. Some use scrubbers, others blend with lower sulfur coal but most all have stacks higher than 400 feet.

    A cargo ship stack is likely about 60 to 90 feet above sea level and the smoke is heavy and untreated. Has your research tracked the amount of time it takes for the particulates to settle into the the ocean surface?

    In the 1970′s US Midwest SO2 particulates had a range of about 300 to 500 miles and at least several days before dissipating into the ecosystem but were emitted at great height. I would think the cargo ship’s particulate emissions would have a lifespan of hours.

    Any comment?

    John McCormick

  25. John McCormick says:

    Having read and reflected on yesterday’s two posts(Hansen and Barton), I am beginning to wonder if Joe Barton is Hansen’s Dr. Faust. What a world!

    John McCormick

  26. Aaron Lewis says:

    #23 Lewis,
    Add in carbon feedbacks, which also have some lag, (clock has been ticking for 40 years) and we see the situation is very interesting.

  27. john lonergan says:

    #26 John McCormick

    Does that make the Kochs equal to ‘The brothrs Mephistopholes’?

  28. Joan Savage says:

    What ship atmospheric emissions reach the stratosphere?

    The negative forcing from volcanic ejecta is largely due to what reaches the stratosphere, where it has a global effect.

    References are in comment #29 to Science Sunday post
    http://climateprogress.org/2011/04/17/aerosol-geoengineering-economics/

    Any chance of a mass balance of negative and positive forcings from shipping?

  29. John McCormick says:

    RE # 28

    Assume the Koch brothers devise a plot to tempt Barton and God approves.

    Mephistopheles is allowed to tempt Faust because God wants to prove to him that human beings have a capacity for good, beauty, and redemption. Mephistopheles, being the Devil, is a supreme pessimist about humanity’s potential. The Lord, however, believes that through tests of extreme emotion, individuals will find their own redemption and prove that God’s creation is worth extolling.

    In Barton’s case, that is an open question.

    John McCormick

  30. Lewis C says:

    Aaron -

    The carbon > carbon > warming feedbacks are indeed a potent factor in the spread of threats we face.

    - For those not aware of this, it was reported in Nature in 2003 that continuing the current trend of CO2 emissions would generate feedback emissions (from the resulting microbial decay of peat) that would equal the entire current annual anthro-CO2 output by 2065.

    Given that CO2 emissions have risen way above trend since 2003, continuing our present path would generate that ruinous scale of feedback emissions long before 2065.

    All of which amounts to further evidence of the imperative need not only to agree a binding global treaty to allocate national emissions rights under a scientific contraction curve, but also to establish a global program of carbon recovery – via afforestation for biochar & energy and via any other globally affordable means – in order to cut airborne CO2 asap and thereby halt the carbon > carbon > warming feedbacks.

    Regards,

    Lewis