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Two degrees

Filed under: — david @ 8 July 2009

The countries of the G8 today approved a target of 2° C rise in global average temperature above the natural, preanthropogenic climate, that they resolve should be avoided. The Europeans have been pushing for 2 degrees as a target maximum temperature for several years, but this is something of a development for the Americans. We posted recently on two new papers about what it would take to limit global average warming, finding that it would require fairly strong change in trajectory. About 2° C as a target, we wrote,

… even a “moderate” warming of 2°C stands a strong chance of provoking drought and storm responses that could challenge civilized society, leading potentially to the conflict and suffering that go with failed states and mass migrations. Global warming of 2°C would leave the Earth warmer than it has been in millions of years, a disruption of climate conditions that have been stable for longer than the history of human agriculture. Given the drought that already afflicts Australia, the crumbling of the sea ice in the Arctic, and the increasing storm damage after only 0.8°C of warming so far, a target of 2°C seems almost cavalier.

Nevertheless, we view today’s development as a constructive step.

411 Responses to “Two degrees”

  1. 351
    Hank Roberts says:

    > Zeebe

    Author of quite a bit of recent work on ocean acidification and biological responses over time, including paleo. I’m wondering if this is moving toward identifying more of the biological feedbacks and getting more of a sense of how fast biology can change, adding a new forcing.

    Here’s one for example:

  2. 352
    Hank Roberts says:

    14 pages worth reading, free download:
    nature reports climate change | VOL 3 | JUL 2009

  3. 353
    Patrick 027 says:

    If you store radioactive waste in a safe place not so dense as to meltdown but dense enough to build up heat, you’ll get a geothermal resource.

    I’m no nuclear enthusiast but I still think it would be cool to see if there is some pathway to make Ga,Rh,Ru,Pd,Ag,In,Te,Xe,Re,Os,Ir,Pt,Au as stable end products from some nuclear reactions.

  4. 354
    Hank Roberts says:

    Cheeses … check the first Google result for that quote: “There appears to be something fundamentally wrong with the way temperature and carbon are linked in climate models.”

    Then look up recent scholarly work on the PETM.
    This is not good news. Behind the fancy scientific words, what they’re describing is devastation. E.g.

    Anyone heard from Peter Ward lately?

  5. 355
    James says:

    Chris Dudley says (15 Jul 2009 at 2:37 pm):

    “With nuclear waste, one has to wait too long to harvest the energy from the decay. Your harvesting machine won’t last long enough.”

    I guess I’m missing something: it’s the fact that an isotope decays rapidly that makes it hazardous nuclear waste, isn’t it? So if it takes a long time to decay – say like C-14 – would it still be a problem?

    “And, it is that lack of any mechanical solution that leads to transmutation as the solution. Unfortunately, that takes energy.”

    Err… Why? Sure, it would take energy to initiate the transmutation, but (with appropriate technology) it seems as though you should get more out than went in.

    “I guess you thing the proton may be unstable?”

    I thought that had been demonstrated? Or has the bleeding edge of physics moved the goalposts again?

  6. 356
    Hank Roberts says:

    Further reminder that despite the USAToday story mentioned above
    with its wonderful pullquote* the statement there
    is no surprise. Here’s just one of many recent modeling papers talking about the missing information we need to better fit what we know about the past to what’s happening now, and why now is different:

    “… The sensitivity of radiative forcing to the carbon cycle

    Ice-core records of glacial-interglacial cycles provide considerable insight into the coupling of the carbon cycle and climate …. Here our aim is to assess how representative our understanding of these relatively recent events is when considering past geological periods or the future after massive anthropogenic CO2 release….

    For the present day, a recent comparison of 11 coupled climate-carbon cycle models reveals a positive feedback between carbon and climate in all cases13: the inclusion of the carbon cycle leading to enhancement of global warming of between 0.1 degC and 1.5 degC in projections over the next 100 years. However, this high sensitivity need not have always applied further back in the geologic past owing to changes in the buffered carbon inventory IsubB.

    Our study suggests that the influence of changes to the carbon
    cycle on climate is stronger now than over much of the past 400 Myr and will remain strong in the near future with fossil-fuel CO2 release and ocean acidification. For the modern era, we suggest that for every 1,000 PgC emitted to the atmosphere, there will be an added radiative forcing of 1:5Wm2 lasting for millennia. In a similar way, terrestrial carbon and ocean ecosystem feedbacks can potentially modify this radiative forcing by up to about 30% (refs 1,13). Consequently, it is an inopportune time to perturb the carbon system. The relationships developed here provide an elegant way to reveal the climate sensitivity to the carbon system and should be viewed as the first part of a model hierarchy to understand how the coupled carbon-climate system operates29….”


    But, lordy, some editor at USAToday is a genius. That story went up yesterday. I hope some sociologist will do a proper study of how this pullquote propagates and how long it lasts.

    As of this moment, Google finds:

    Results … about 1,220 for “There appears to be something fundamentally wrong with the way temperature and carbon are linked in climate models.”

  7. 357
    sidd says:

    James wrote:
    “Of course there are no actual stable isotopes of anything, just ones with very much greater half-lives.”

    I was not aware that the proton was demonstrated to be unstable. In fact I thought that the lower limit on proton half life was on the order of something ridiculous like 1e33 yr, well on the way to Poincare recurrence times…

  8. 358
    sidd says:

    o dear i made a misattribution here:

    the following phrase:
    “Of course there are no actual stable isotopes of anything, just ones with very much greater half-lives.”

    was actually written by Mr. Chris Dudley.

  9. 359
    Chris Dudley says:

    Sidd (#358),

    No, that was James. I agree that the proton has not yet been shown to be unstable.

  10. 360
    Hank Roberts says:

    well, I wouldn’t have believed it, but — that quote that’s filling up the blogosphere tonight?

    It’s not something that USAToday got in an interview.

    Rice University’s PR department put it out as a press release:

    —- entire press release follows —-
    —–note how different the implications are
    —–when you read the whole thing —-


    CONTACT: Jade Boyd
    PHONE: 713-348-6778

    Global warming: Our best guess is likely wrong
    Unknown processes account for much of warming in ancient hot spell

    No one knows exactly how much Earth’s climate will warm due to carbon emissions, but a new study this week suggests scientists’ best predictions about global warming might be incorrect.

    The study, which appears in Nature Geoscience, found that climate models explain only about half of the heating that occurred during a well-documented period of rapid global warming in Earth’s ancient past. The study, which was published online today, contains an analysis of published records from a period of rapid climatic warming about 55 million years ago known as the Palaeocene-Eocene thermal maximum, or PETM.

    “In a nutshell, theoretical models cannot explain what we observe in the geological record,” said oceanographer Gerald Dickens, a co-author of the study and professor of Earth science at Rice University. “There appears to be something fundamentally wrong with the way temperature and carbon are linked in climate models.”

    During the PETM, for reasons that are still unknown, the amount of carbon in Earth’s atmosphere rose rapidly. For this reason, the PETM, which has been identified in hundreds of sediment core samples worldwide, is probably the best ancient climate analogue for present-day Earth.

    In addition to rapidly rising levels of atmospheric carbon, global surface temperatures rose dramatically during the PETM. Average temperatures worldwide rose by about 7 degrees Celsius — about 13 degrees Fahrenheit — in the relatively short geological span of about 10,000 years.

    Many of the findings come from studies of core samples drilled from the deep seafloor over the past two decades. When oceanographers study these samples, they can see changes in the carbon cycle during the PETM.

    “You go along a core and everything’s the same, the same, the same, and then suddenly you pass this time line and the carbon chemistry is completely different,” Dickens said. “This has been documented time and again at sites all over the world.”

    Based on findings related to oceanic acidity levels during the PETM and on calculations about the cycling of carbon among the oceans, air, plants and soil, Dickens and co-authors Richard Zeebe of the University of Hawaii and James Zachos of the University of California-Santa Cruz determined that the level of carbon dioxide in the atmosphere increased by about 70 percent during the PETM.

    That’s significant because it does not represent a doubling of atmospheric carbon dioxide. Since the start of the industrial revolution, carbon dioxide levels are believed to have risen by about one-third, largely due to the burning of fossil fuels. If present rates of fossil-fuel consumption continue, the doubling of carbon dioxide from fossil fuels will occur sometime within the next century or two.

    Doubling of atmospheric carbon dioxide is an oft-talked-about threshold, and today’s climate models include accepted values for the climate’s sensitivity to doubling. Using these accepted values and the PETM carbon data, the researchers found that the models could only explain about half of the warming that Earth experienced 55 million years ago.

    The conclusion, Dickens said, is that something other than carbon dioxide caused much of the heating during the PETM. “Some feedback loop or other processes that aren’t accounted for in these models — the same ones used by the IPCC for current best estimates of 21st Century warming — caused a substantial portion of the warming that occurred during the PETM.”

    —–end Rice University press release—–
    I look forward to hearing what the scientists make of the coverage. Perhaps they should offer the science education campaigners this as an example and ask how to improve on it.

  11. 361
    Patrick 027 says:

    James – the C-14 concentration in C is very very very very small.

    Is it possible that the the sufficient power output for danger is less than the sufficient power output for an economic energy source?

    But I tend to agree with you (with very little specialized technical knowledge on the subject) that it should be possible to produce stable isotopes with net energy output.

    Suppose we wanted to make nuclear waste a gold mine. The approach I would start with is to look at the various stable good nuclei, find which isotopes with short half lives decay to that state, and trace back the chain of reactions to see what kind of isotopes we might want to produce by bombarding some other isotopes with neutrons… and maybe some isotope of lead or mercury would do the trick. Problem – if the desired isotope easily absorbs more neutrons, the isotope would be destroyed as it is produced. What might be done is to dissolve the isotope in the cooling fluid that goes through the reactor core, wherein the desired product isotope precipitates from solution outside of the core and is removed periodically. The reactant isotope would be from the spent fuel of another reactor…(?)

  12. 362
    Mark says:

    “I thought that had been demonstrated? Or has the bleeding edge of physics moved the goalposts again?

    Comment by James”

    Uh, you didn’t keep up, did you.

    The decay of the proton depends on the weight of one of the neutrinos (tau? I can’t remember off top of my head). If the neutrino is massless then the proton doesn’t decay (there’s no mass particle that it can decay to that isn’t more energetic than it). But the lower the mass of the neutrino, the longer the half-life of the proton.

    So, you can’t stop neutrinos and definitely can’t stop enough to weigh them, so people have been looking at the decay time to give a maximum weight to the neutrinos.

    A massive neutrino would explain the scarcity of neutrinos from the sun: they are transforming to another neutrino.

    But the proton hasn’t been seen to decay, making its decay time as someone else says something of the order 10^40 seconds.

  13. 363

    I know, Hank–the headline could have been “Could climate change be twice as large as we thought?”

    The actual story, as you point out, is cause for *increased* concern, yet that aspect is not at all captured by the headline. I’ve wondered why, and resigned myself to the fact that I will likely need to explain this repeatedly over the next little while.

  14. 364
    dhogaza says:

    Cheeses … check the first Google result for that quote: “There appears to be something fundamentally wrong with the way temperature and carbon are linked in climate models.”

    It’s entertaining, in a perverse way, to watch Leif Svaalgard to to educate the WUWTers that the fact that the researchers’ belief that their work points to a possible sensitivity to CO2 doubling in the 5C+ range is somehow good news for deniers.

    I look forward to hearing what the scientists make of the coverage. Perhaps they should offer the science education campaigners this as an example and ask how to improve on it.

    How do you improve it to the point where willful misrepresentation, quote-mining, and flat-out inability to understand what one reads is no longer a problem?

  15. 365
    Rod B says:

    Hank (356), I haven’t yet read the paper but a couple of thoughts from your excerpt don’t seem intuitively obvious: 1) why would CO2 coming from burning fossil fuel be more forcing than CO2 from any other source. It’s hard to imagine that IR would be absorbed differently in a pile of CO2 that has a slightly different isotope ratio. 2) Why would ocean acidification occur only (or much more) with today’s CO2 and not yesteryear’s. Again, how does the ocean know the difference? Or did I misread your excerpt?

  16. 366
    Mark says:


    1) It wouldn’t.

    Where do you get the idea it is?

    2) Because yesteryear’s CO2 wasn’t increasing, it was in equilibrium.

    I think you did misread.

  17. 367
    John E. Pearson says:

    There are numerous things that can be done besides finding new ways to generate energy.

    This article quotes Steven Chu citing a calculation done by LBL scientist Art Rosenfeld who claims that painting the worlds roofs white will result in the equivalent removal of 44 Gtons of CO2.

    This next sounds like “passive solar” but it is substantially different: “Passive houses.” I think I would put both this and the white roof idea in the conservation category.

    one more:

    Extinguishing all the coal seam fires in the world would make a substantial difference. One was put out in China a few years ago that (according to the news articles I read) was generating as much CO2 as the entire US light truck/automobile fleet.

  18. 368
    Rod B says:

    Mark (), I was referring to this for Hank’s excerpt (356)

    the influence of changes to the carbon cycle on climate is stronger now than over much of the past 400 Myr and will remain strong in the near future with fossil-fuel CO2 release and ocean acidification. For the modern era, we suggest that for every 1,000 PgC emitted to the atmosphere, there will be an added radiative forcing of 1:5Wm2 lasting for millennia.

    I read that as it being “stronger now than… the past 400 Myr” from fossil fuel CO2 release and acidification. It implies the “modern era” forcing will be 1.(sic)5 Wm2 additive. Am I reading it wrongly?

    Doesn’t acidification depend on the instantaneous concentration (partial pressure) and the chemical state of the ocean whether it is in equilibrium or not?

  19. 369
    Hank Roberts says:

    Rod B, you should at least click the link and look at the paper.
    Mark’s right. The ‘thoughts’ you ask about are not in the excerpt, nor in the paper. I think you’ve failed to consider rate of change and the difference between geological time and current events.

  20. 370
    Mark says:

    “Mark’s right.”

    And all I needed was a mindset that was thinking “how would that work?” rather one that says “this isn’t going to work”.

    The first one is what I consider a skeptic view.

    The second one denialist.

  21. 371
    Patrick 027 says:

    Rod B –

    “For the modern era, we suggest that for every 1,000 PgC emitted to the atmosphere, there will be an added radiative forcing of 1:5Wm2 lasting for millennia.”

    I’m not sure exactly what 1:5 means here – I would normally read that as a ratio.

    But from the context, I’m infering that for any given anthropogenic CO2 increase, there will be radiative forcing greater than that CO2 alone, because of CO2 feedback emissions.

    Such geochemical feedbacks can easily depend on the present state of things, and not just the present climate, but the locations and abundances of various geochemical reservoirs and frozen bodies of water, evolved species, soils, topography, etc, that has been shaped by climate and other factors over time.

    And this paper is suggesting that the present day CO2 feedback may be stronger than what it would have been if we’d done this experiment at many times in the past.

    *** One complexity in how to describe this: over the last several decades or so, at least, there has been some fraction (40 %?) of anthropogenic CO2 releases that have been taken out of the atmosphere (over and above the amount taken out of the atmosphere that balances the natural additions to the atmosphere), perhaps mainly as a direct biogeochemical feedback (increased CO2 favoring more rapid biological fixation of C, net flux of CO2 into water until equilibrium for the given storage of other involved chemical species in the upper ocean) fairly promptly. Seeing this as a baseline, positive CO2 feedback from temperature changes, or a running out of capacity for greater uptake from CO2 accumulation, would be seen as adding more CO2 to the air in addition to anthropogenic releases, but it would have to surpass some level before it would result in a total atmospheric accumulation of CO2 greater than anthropogenic emissions (first, as a rate, and later, cummulative change).

    The geochemistry of the ocean right now depends on what has been happening up to now, and pH can be buffered over time from dissolution of carbonate minerals and additions of Ca, Mg(?), etc, ions to the ocean from chemical weathering.

  22. 372
    Hank Roberts says:

    The puzzling colons in that web page like “1:5” are some sort of html font hiccup; look at the actual PDF file — what look like colons are decimal points in the original.

  23. 373
    Hank Roberts says:

    Key point: rate of change.

    > pH can be buffered over [geological] time from
    > dissolution of carbonate minerals and additions
    > … from chemical weathering.

    Look at the PDF. That’s part of what they’re saying here.
    We’re adding CO2 far faster than has happened in the past.
    And in the past the _long_term_ temperature increase following an increase in CO@ was the PETM excursion.

    The planet was already much warmer at the time — and many other things were different. But the spike (very fast _in_geologic_time_terms_) in temperature was huge.
    More here, describing an earlier article that appeared in Science: 8 DECEMBER 2006 VOL 314:

    See also the related articles linked at the bottom of that page.

  24. 374
    Hank Roberts says:

    Ah, the irony, it burns.

    Those of you reading on the septic side of the bogusphere may have seen a lot about climate models needing improvement in the last couple of days. This sound familiar? And would you recognize this in what you’re reading from people crying out how the models need improvement?

    “… The light carbon isotope ratio found both in the ocean and on land during the PETM is the key to understanding the causes of the rapid changes. Whatever triggered the warming involved the release of large quantities of light carbon into the ocean-atmosphere system.

    Paleoceanographer Gerald Dickens of Rice University has suggested that this light carbon came from microbially generated methane buried in sediments along the slopes of the continental shelves (see Geotimes, November 2004).

    This methane exists along our coasts today, frozen in the sediment at low temperatures and high pressures. The microbes produce methane highly concentrated in carbon-12. An increase in temperature or a decrease in pressure in the ocean waters overlying these sediments can melt this buried methane and allow it to bubble to the surface.

    For several years, this methane “hiccup” was regarded as the best possible explanation for the rapid warming at the PETM. Despite the fact that it nicely explained the carbon-12 increase, however, this hypothesis left a few questions unanswered.

    First, the hypothesis did not invoke a mechanism for warming ocean waters to destabilize the methane (although it is possible that ocean waters reached a threshold temperature after warming gradually for millions of years). Second, the quantity of methane necessary to explain the carbon isotope ratio, as calculated by Dickens, would be much less than that required to warm ocean and atmosphere temperatures to the extent estimated by PETM temperature proxies and calculated by physical climate models.

    Dickens calculated that the release of methane at the PETM would result in an approximate 60-parts-per-million increase in atmospheric carbon dioxide (compared with the modern rise of nearly 100 parts per million in atmospheric carbon dioxide concentration over the 19th century). Climate models suggest that atmospheric carbon dioxide concentrations would need to increase, at the very least, by 1,000 parts per million, to warm high latitudes by 8 to 10 degrees Celsius.

    In 2004, new evidence from the Norwegian Sea for an alternate source of methane helped scientists to revise ideas about events at the PETM. A team of geologists led by Henrik Svensen of the University of Oslo discovered hydrothermal vent complexes — thousands of them — dating back to the Paleocene-Eocene boundary. These vents form when melted rock from the mantle seeps into carbon-rich sediments. The heating and melting of these sediments can lead to a buildup of gases — and, ultimately, an explosive release. …”

  25. 375
    Doug Bostrom says:

    Some output from the World Laboratory. Climate change rubber begins to hit the geopolitical road:

    “Hopelessly overcrowded, crippled by poverty, teeming with Islamist militancy, careless with its nukes—it sometimes seems as if Pakistan can’t get any more terrifying. But forget about the Taliban: The country’s troubles today pale compared with what it might face 25 years from now. When it comes to the stability of one of the world’s most volatile regions, it’s the fate of the Himalayan glaciers that should be keeping us awake at night.

    Another increasingly important factor will soon heighten the tension: Ninety percent of Pakistan’s agricultural irrigation depends on rivers that originate in Kashmir. “This water issue between India and Pakistan is the key,” Mohammad Yusuf Tarigami, a parliamentarian from Kashmir, told me. “Much more than any other political or religious concern.”


    In 1960, India and Pakistan agreed to divide the six tributaries that form the Indus River. India claimed the three eastern branches, which flow through Punjab. The water in the other three, which pass through Jammu and Kashmir, became Pakistan’s. The countries set a cap on how much land Kashmir could irrigate and agreed to strict regulations on how and where water could be stored. The resulting Indus Waters Treaty has survived three wars and nearly 50 years. It’s often cited as an example of how resource scarcity can lead to cooperation rather than conflict.

    But the treaty’s success depends on the maintenance of a status quo that will be disrupted as the world warms. Traditionally, Kashmir’s waters have been naturally regulated by the glaciers in the Himalayas. Precipitation freezes during the coldest months and then melts during the agricultural season. But if global warming continues at its current rate, the Intergovernmental Panel on Climate Change estimates, the glaciers could be mostly gone from the mountains by 2035. Water that once flowed for the planting will flush away in winter floods.

    Research by the global NGO ActionAid has found that the effects are already starting to be felt within Kashmir. In the valley, snow rarely falls and almost never sticks. The summertime levels of streams, rivers, springs, and ponds have dropped.

    Normally, countries control such cyclical water flows with dams, as the United States does with runoff from the Rocky Mountains. For Pakistan, however, that solution is not an option. The best damming sites are in Kashmir, where the Islamabad government has vigorously opposed Indian efforts to tinker with the rivers. The worry is that in times of conflict, India’s leaders could cut back on water supplies or unleash a torrent into the country’s fields. “In a warlike situation, India could use the project like a bomb,” one Kashmiri journalist told me.

    Water is already undermining Pakistan’s stability. In recent years, recurring shortages have led to grain shortfalls. In 2008, flour became so scarce it turned into an election issue; the government deployed thousands of troops to guard its wheat stores. As the glaciers melt and the rivers dry, this issue will only become more critical. Pakistan—unstable, facing dramatic drops in water supplies, caged in by India’s vastly superior conventional forces—will be forced to make one of three choices. It can let its people starve. It can cooperate with India in building dams and reservoirs, handing over control of its waters to the country it regards as the enemy. Or it can ramp up support for the insurgency, gambling that violence can bleed India’s resolve without degenerating into full-fledged war. “The idea of ceding territory to India is anathema,” says Sumit Ganguly, a professor of political science at Indiana University. “Suffering, particularly for the elite, is unacceptable. So what’s the other option? Escalate.”

    Rising global temperatures are putting the whole world under stress, and the first countries to succumb will be those, such as Sudan, that are least able to adapt. Compare the Netherlands and Bangladesh: Both are vulnerable to rises in sea levels, with large parts of their territory near or under the level of the waves. But the wealthy Dutch are building state-of-the-art flood-control systems and experimenting with floating houses. All the impoverished Bangladeshis can do is prepare to head for higher ground. “It’s best not to get too bogged down in the physics of climate,” says Nils Gilman, an analyst at Monitor Group and the author of a 2006 report on climate change and national security. “Rather, you should look at the social, physical, and political geography of regions that are impacted.”

    Indeed, with a population half that of the United States crammed into an area a little smaller than Louisiana, Bangladesh might be among the most imperiled countries on Earth. In a normal decade, the country experiences one major flood. In the last 11 years, its rivers have leapt their banks three times, most recently in 2007. That winter, Cyclone Sidr, a Category 5 storm, tore into the country’s coast, flattening tin shacks, ripping through paddies, and plunging the capital into darkness. As many as 10,000 people may have died. ”

    The rest of the story:

  26. 376
    SecularAnimist says:

    Here’s some good news on the clean energy front:

    Global wind energy potential is considerably higher than previous estimates by both wind industry groups and government agencies, according to a Harvard University study published last week in the Proceedings of the National Academy of Sciences of the United States [PDF]…

    Using data from thousands of meteorological stations, the Harvard team estimated the world wind power potential to be 40 times greater than total current power consumption. A previous study cited in the paper put that multiple at about 7 times …

    In the lower 48 states, the potential from wind power is 16 times more than total electricity demand in the United States, the researchers suggested – significantly greater than a 2008 Department of Energy study that projected wind could supply a fifth of all electricity in the country by 2030.

    While remote regions of Russia and Canada have the greatest theoretical potential, the Harvard study pointed out that there are real gains to be made in high-emission nations, especially China, which has been rapidly constructing coal plants. “Large-scale development of wind power in China could allow for an 18-fold increase in electricity supply relative to consumption reported for 2005,” the Harvard study said …

    The authors based their calculations on the deployment of 2.5- to 3-megawatt wind turbines situated either in accessible rural areas that are neither frozen nor forested, or relatively shallow offshore locations. They also used a conservative 20 percent estimate for capacity factor, a measure of how much energy a given turbine actually produces.

    Yet more evidence that the world has vast commercially-exploitable wind and solar energy resources, that are more than sufficient to produce more than enough electricity for all current uses, plus the electrification of ground transport, without fossil fuels or nuclear power.

    So … what are we waiting for ???

  27. 377
    Rod B says:

    Hank, Patrick 027, et al: I could be picky and say the syntax could have been better, but it’s (now) clear that “anthropogenic CO2” is simply a timely representative example and the anthropological part is not a cause per se — any source of CO2 would suffice.

    This looks interesting and I need to study it all more, but thought I’d get my clarification/misunderstanding out of the way.

  28. 378
    Patrick 027 says:

    “the anthropological part is not a cause per se — any source of CO2 would suffice”

    Yes of course – the main variation is that, at any one moment in time, each unit increase of atmospheric CO2 has less radiative forcing than the last, following the logarithmic proportionality discussed earlier.

    PS isotopic variations probably would shift the spectrum around in some way, but the vast majority of all C reservoirs is C-12; variations in less-abudant isotopes (13,14) are helpful for tracing sources and fluxes.


    PS the quickest possible way to estimate global wind energy –

    convection is about 100 W/m2, an average tropospheric temperature maybe ~ 255 K, surface temperature ~ 288 K, heat engine efficiency = 1 – 255/288 = 33/288 ~= 12 %, implies global mechanical energy generation of about 12 W/m2; if x % (50 % ?) is dissipated by damping of gravity waves in the bulk of the air (from thunderstorm CAPE energy) and 1/2 of the remainder is dissipated in the boundary layer (the part dissipated near the surface is the accessible part by conventional means)… well, you get the idea.

  29. 379
    Lynn Vincentnathan says:

    RE #376 & wind potential. I sort of figured someone must be underestimating it.

    Here’s an interesting solution — much smaller wind generators in urban areas (solving the bird problem) — less energy, but more could be used all over the place:

    posted at:

    NYC water towers seen as ground for “wind farms”
    Thu Jun 11, 2009, By Joan Gralla

    NEW YORK (Reuters) – New York City could become the grounds for a new kind of urban wind farm if a Cleveland-based mechanical engineer has his way.

    Cleveland State University’s Fenn College of Engineering on Thursday said it will unveil a new wind turbine design by one of its professors, Majid Rashidi, that could attach to the sides of the water storage tanks that sit on the rooftops of many city apartment buildings.

    Mayor Michael Bloomberg, who has made green programs a centerpiece of his administration, last August proposed crowning the city’s bridges, skyscrapers and shorelines with turbines, but critics said they would be impractical and possibly hazardous.

    But Rashidi said his turbines solve a key stumbling block of harnessing wind power effectively in crowded urban areas because they accelerate the flow of wind through four rotating turbines. That allows the turbines to work where the wind speed otherwise would be too low.

    “In the urban settings, usually because of the existence of buildings, you don’t get the high speeds needed,” he said.

    The turbines, which are fixed to the sides of a cylinder, already seem to be outpacing a competing turbine that sits on a traditional mast.

    “Today, I saw on the roof, my four were all rotating; the one stationed on the mast was not moving, so proof of the concept has already been shown,” Rashidi said.

    Rashidi’s concept takes advantage of the city’s existing water towers that were designed to hold thousands of pounds of water and thus could handle any forces the turbines exert, said Richard Steiner, who is working with Rashidi.

    Rashidi’s four turbines could produce 8 kilowatts per hour. That compares with the 2,000 or so kilowatts produced by the much bigger turbines that sit atop tall masts.

    The Cleveland Indians baseball team is expected to be the first to install the turbines at its home stadium.

    Steiner said he hopes the team will agree to use them for its “Progressive Field” stadium within 30 to 60 days.

    Bridgett Neely, an energy expert for New York City, said that by late summer the city hopes to clarify how it can encourage the use of wind turbines by smoothing permitting and testing.

    Like many U.S. cities and towns, New York’s zoning and other rules could block rooftop turbines — as well as smaller models the Cleveland experts hope homeowners could use in their backyards.

    New York is likely to start with smaller turbines. Last year, “the ones that made the biggest splash in print, on buildings and bridges, some of that was fanciful,” Neely said.

    She said wind turbines were just one item on Bloomberg’s green energy list, citing six experimental turbines in the East River and a possible city-state offshore wind farm.

    One promising green model is the city-owned Brooklyn Navy Yard’s test of street lamps that run on solar and wind power, a useful feature in the Northeast where clouds can persist for days, according to Baldev Duggal, who invented the Lumi-Solair lamps.

    The Navy Yard, now an industrial park, could reap savings of hundreds of thousands of dollars because of the new lamps’ lower costs. Each lamp has its own power, so no underground wires have to be dug up when they short out.

    The Cleveland professors also are exploring using a helix shape to hold the turbines instead of a cylinder. “We want to make it smaller and even get more acceleration,” Steiner said.

    The swiveling arm and supports for the Cleveland turbines might cost somewhere in the neighborhood of $5,000, Rashidi estimated. “Then you have to buy off the shelf turbines and just hang them up like a chandelier,” he said.

    Critics of windmill farms say they kill birds because they often are located in migratory routes.

    But the Cleveland experts say the much smaller turbines lack the killing force of the wind farms. Those much bigger turbine blades can weigh over 2,000 pounds.

  30. 380
    Hank Roberts says:

    Robert Glennon, author of Unquenchable, America’s Water Crisis and What to Do About It — guest on the Daily Show:

    “… to prevent the water crisis from becoming a catastrophe …”

    “Energy policy pays no attention whatsoever to water issues.”

    “Global warming means that the seas will rise a foot, can’t we use that …..?”

  31. 381
    Hank Roberts says:

    > “anthropogenic CO2″ is simply a timely representative example and …
    > any source of CO2 would suffice.

    That’s one of the basic things necessary to understand anything else.
    Spencer Weart’s a good source to review if this is the first time you got that clear. Much else will now begin to make more sense.

    Next concept probably ought to be ‘rate of change’ — how fast we are increasing CO2 compared to any prior period of time. Weart, again.

  32. 382
    Patrick 027 says:

    … I wonder what portion of the wind energy is transferred to waves and currents … Probably a small fraction, but the energy is naturally transported (as with wind).

  33. 383
    Chris Dudley says:

    Hank (#379),

    Stewart is trying to make hay of the idea that working on climate issues makes water issues worse and as a result Glennon’s views on solar power get garbled. Here is some more detail:

    He seems to misunderstand that it is the average air temperature and not the daytime temperature that makes a difference in dry cooling, but he is a lawyer, not an engineer.

    In the case of Concentrated Solar Power that uses heliostats, one ought to be able to boost night time cooling by providing a low brightness temperature surface (the mirrors) to enhance radiative cooling, though the convective cooling will still dominate. For Sterling engine solar concentrators, one ought to be able to run them in reverse on clear nights to generate a low amount of electricity from built up daytime heat. Even parabolic troughs might run radiative cooling through pipes placed halfway between the collector vacuum pipes and the mirror surface since these pipes would see cool portions of the sky not occupied by the Sun. In fact, most of the plane shadowed by the collecting vacuum pipe is available for cooling.

    So, water is not really an issue for solar power so long as one stops thinking like a fossil fuel power plant designer.

  34. 384
    Lynn Vincentnathan says:

    That’s a very good point, Hank (#380), the water crisis. Some 8 years back we started the Aurora (IL) Conservation Campaign, and we decided to start with water conservation. That also means GW mitigation, since there is an energy component to pumping and heating water, and CC will be reducing our potable water supplies.

    We went to our local water company, and the man told us the water level had gone down 800 feet over the past 100 years of use. Who knew? We were shocked. Why didn’t the people who were using the water know about that? They city thought no one would listen, or they’d get mad.

    Anyway, I got around to reducing our household water consumption by about half, without hardly noticing any difference in lifestyle, and saving $$$ in water bills and gas (to heat the water) bills.

    We moved away and I think the ACC became defunct, but the webpage is still up, & here are the water conservation tips:

  35. 385
    Hank Roberts says:

    Chris, you write
    > average air temperature and not the daytime temperature that
    > makes a difference in dry cooling, but he is a lawyer, not an engineer.

    But for concentrating solar, the kind that boil something to run a turbine, cool the stuff and return it, what matters is the daytime temperature, not the average, right? The temperature _while_operating_, and they operate in the daytime. If they can take off excess heat aqnd have excess power, they might store it for night operation, but pumping heat into a reservoir costs more than radiating it away.

    It’s a heat engine, operating on the difference between the hot end and the cool end.

    Radiators in the shadows pointing at cold north sky makes sense. And I recall one can make ice in the desert the same way; a concentrating solar power plant could also create a ‘cold reservoir’ by radiating heat away from some storage material at night, then dumping waste heat into that in the daytime, perhaps.

    All that adds to costs, and the point of that excellent WaPo opinion piece by Glennon that you point to is the slight extra costs deter this kind of investment, unless adult supervision is present to constrain the cheapest-possible design by the power plant mindset.

    Trading off cotton farming for concentrating solar is a good example of smart planning — take out one of the most water-wasteful subsidized crops we don’t grow very well, and replace it with a plant that uses less water and produces electricity.

  36. 386
    Dan L. says:

    SecularAnimist (#376) “An increase in friction caused by the
    presence of the turbines is likely to be compensated by a decrease
    in frictional dissipation elsewhere. Global average surface temperatures
    are not expected to change significantly although temperatures
    at higher latitudes may be expected to decrease to a modest
    extent because of a reduction in the efficiency of meridional heat
    transport (offsetting the additional warming anticipated for this
    environment caused by the build-up of greenhouse gases). In
    ramping up exploitation of wind resources in the future it will be
    important to consider the changes in wind resources that might
    result from the deployment of a large number of turbines,”

    I can hear Anthony Watts now: “Wind turbines cause Global Calming!”

  37. 387
    David B. Benson says:

    Dry cooling towers consume no water:
    and there certainly are many in use.

  38. 388
    Chris Dudley says:

    Hank (#385),

    With dry cooling, one wants to have enough surface area so that convective cooling can do the same job that evaporative cooling can do. If you only cool half the time (not at night) then you double the needed surface area, which is a cost issue. So, you would do better to cool all the time rather than only when producing power.

    Your idea of using radiators below the parabolic trough is interesting. I was thinking of using the region below the focus but above the reflecting surface though. This gives a view of sky which is not occupied by the Sun.

  39. 389
    Hank Roberts says:

    > cool all the time
    But a heat engine works with the difference between the hot and cold side while it’s working. Yeah, if there’s a ‘cold reservoir’ somewhere to chill all night then use to cool the radiators during the day, that might work. But that’s not in the designs I see pictured, which are self-contained Stirling engines using hydrogen gas, a sealed system; heat it, use the hot gas for work, cool the gas, return it.

  40. 390
    Doug Bostrom says:

    Geopolitical maneuvering makes climate science look oh-so-tractable by comparision.

    India rejects legally binding carbon emissions targets:

    NEW DELHI — India served notice on Sunday that it remains opposed to legally binding targets to reduce emissions of carbon dioxide, digging in its heels against the United States as the Obama administration begins marshaling support for a new global agreement on climate change.

    India voiced its rejection of the American position in an awkwardly public forum: during a visit by Secretary of State Hillary Rodham Clinton to an energy-efficient office building on the outskirts of New Delhi that was supposed to celebrate cooperation between India and the United States on climate policy.

    In a closed-door meeting with Mrs. Clinton after she marveled at the building’s high-tech features, India’s environment minister, Jairam Ramesh, said, “There is simply no case for the pressure that we, who have among the lowest emissions per capita, face to actually reduce emissions.”

    “If this pressure is not enough,” he continued, “we also face the threat of carbon tariffs on our exports to countries such as yours.”

    The rest of the story:

  41. 391
    Jerry Toman says:


    There is a “cold reservoir” (circa -50 C) for heat rejection to complete the Rankine (or Stirling) cycle located about 5 miles above sea level, anywhere, including above a solar thermal plant in the desert, that would vastly improve the efficiency versus rejecting heat to the earth’s surface.

    Radiating this amount of heat (when needed) is not feasible and some type of dry cooling tower is required.

    The upper level is accessible if one is clever enough to devise a method to do so. Louis Michaud has accomplished this, and is only awaiting support from enough prominent atmospheric scientists like yourself so the funding necessary to move forward can be obtained.

    What, in your knowledge of Atmospheric Science makes you hesitant to do support this scheme–inquiring minds want to know!

    Do you disagree with Nilton Renno, a NASA expert in vortices, who says that “the science is solid”–and if you do, in what respect do you disagree?

  42. 392
    Chris Dudley says:

    Hank (#389),

    The Sterling engine set up you are thinking of is not what people mean by dry cooling. Dry cooling is for turbines, and it really just means that water is not evaporated to the atmosphere, not that water is not used as a cooling fluid. Heat is transfered to the air convectively or through the use of fans from a warm surface. That surface is warmed by water used to condense steam from a turbine though. The “dryness” comes from not losing any water to the air.

  43. 393
    Hank Roberts says:

    Jerry Toman, there are at least three errors in your notion of me as a “prominent atmospheric scientist” — can you find them? This suggests you need to start from the basics and read more carefully. I’m an amateur reader here, just like you are.

    As to the name you mention: nothing

    Got science?

  44. 394
    Jerry Toman says:


    There are plenty of peer-reviewed articles that can be found at:

    You or any of the “official” contributors are welcome to point out any mistakes you might find in the above articles.

    It would appear that Google’s “Scholar” database could be missing one or more “Aces”. I’m sure it will be corrected in time.

  45. 395
    Patrick 027 says:

    Hank Roberts, Jerry Toman –

    I believe what Jerry is refering to is the idea of using a column of spinning air to transfer the mechanical energy from CAPE (potential buoyant energy of hot and/or humid air near the surface) in an updraft to the surface. Because contraction of the vortex tends to require faster rotation (conservation of angular momentum), which increases centrifugal acceleration, which opposes contraction, it becomes hard for air to flow in sideways to take the space of warmer air that is rising when the air is spinning; thus, a rising column of air can pull up on air from below. Indeed, this is how mesocyclones supply energy to tornados.

    Basically, the idea is to construct a solar tower without an actual solid structure (except near the surface).

    I think it’s a great idea, though I’m concerned that turbulent mixing of momentum might degrade performance too much…

  46. 396
    Hank Roberts says:

    Jerry asked the same question and made the same request for support a couple of years ago.

    The site mentions a scientific ‘Advisory Board’ naming several well known universities and one scientist — you might do better having them make the contacts asking scientists for support. Posting on blogs isn’t optimal to get attention.

  47. 397
    John E. Pearson says:

    Re 393 & 394:


    Google scholar isn’t missing any “aces”.

  48. 398
    Jerry Toman says:

    I’ve supplied the group with a list of Louis Michaud’s publications which indicate that there is plenty of renewable energy in the atmosphere or from so-called “waste heat”, which could potentially be harvested with the Atmospheric Vortex Engine for which he has been grated patents.

    Why doesn’t the group deal with the actual content of these articles, rather than ruminating over some silly “list”?

  49. 399
    Hank Roberts says:

    Jerry Toman, Ray Pierrehumbert suggested what’s needed, in reply to your posting of
    30 Jan 2008 at 3:23 pm
    Are you involved with Michaud? Did you pass that on to Michaud as a recommendation?

  50. 400
    Hank Roberts says:

    PS to Jerry — Raypierre in that response (30 Jan. 2008) recommended Michaud obtain a computational fluid dynamics simulation, then on that basis build a model.

    The Michaud website mentions having obtained a computational fluid dynamics study of a small-scale model (two pictures, but no numbers nor link). So he might have something to interest some of the people in the field.