Do Variations in the Solar Cycle Affect Our Climate System?

There have been many arguments as to whether or not the eleven-year sunspot cycle affects our weather and climate. With our increased ability to monitor the sun, we are now aware that there is a small change in the total solar irradiance accompanying shifts from solar maximum conditions (with many sunspots) to solar minimum (with, basically, none). There is also a more substantial change in the ultraviolet (UV) portion of the solar spectrum, with direct impacts primarily in the stratosphere (above ~10km).

Figure 1, at right. Total solar irradiance over the past three solar cycles, since 1975, varying between 1365 and 1367 W/m². (Click for large JPEG or PDF.)

The effect of these changes on our temperature record has been noted by some researchers, and, like the change in solar irradiance, it too appears to be small. But there is little agreement on just how that change arises. Furthermore, there are claims that the sunspot cycle is associated with changes in storm tracks and rainfall. How could this happen with so little change in total energy?

To understand the processes involved, we recently completed an extensive series of climate model experiments, involving 1600 simulated years with varying UV and total solar irradiance (TSI). Our experiments show that the solar cycle influences tropospheric rainfall patterns in a manner consistent with some observations, with increased solar activity favoring precipitation north of the equator (for example, the South Asian monsoon) and decreased precipitation both near the equator and at northern mid-latitudes. The word “favoring” is used advisedly; in the experiments it is a “weighting of the dice”, an increase in the likelihood of these effects while accounting for less than one standard deviation of the variability (a result found in observations as well). Locally it can account for 15-20% of rainfall totals. The influence also seems to have been modified by global warming, and so its effectiveness may change with time. The impact of the solar cycle on precipitation in the model experiments arises from two different mechanisms, the first involving UV changes, the second total solar irradiance.

The increase of incident solar UV during solar maximum conditions leads to increased generation of stratospheric ozone in the mid-to-upper stratosphere, which ultimately results in greater ozone in the tropical lower stratosphere. This helps warm that region via both short- and long-wave absorption. In response to this more stable vertical profile for tropical tropospheric processes, tropical convection preferentially shifts off the equator, favoring monsoonal effects during Northern Hemisphere summer and on the annual average.

Figure 2, at right.Results show the percentage of the 1600 years of experiments during which solar maximum conditions produced increased (green) or decreased (brown) precipitation at different latitudes on the annual average. The top panel shows the experiments which used climatological (unchanging) SSTs; here the influence comes primarily from the solar UV variations affecting the stratosphere. The bottom panel is for the experiments with historically-varying SSTs, in which TSI changes have influenced the surface. Precipitation decreases occur greater than 50% of the time south of the equator in both figures, but decreases in mid-latitudes result primarily from the UV changes (top figure). Recent variations in SSTs due to other sources (such as greenhouse gases) appear to have minimized the mid-latitude response. (Click for large GIF or PDF.)

In addition, the solar-plus-ozone change leads to increased tropical stratospheric warming in the mid-to-upper stratosphere during solar maximum conditions. Higher latitudes during Southern Hemisphere winter receive no such augmentation, and the increased latitudinal temperature gradient results in stronger stratospheric west winds. Via the interaction of these wind changes and planetary waves propagating up from the troposphere, the circulation in the stratosphere weakens, a response characterized by greater relative upwelling in the Southern Hemisphere extratropics, and more downwelling in the northern extratropics. This downwelling has a tendency to extend into the troposphere, limiting convection and rainfall during Northern Hemisphere summer at these latitudes, producing drier conditions. This effect is seen in some paleoclimate records and has been attributed to solar influence.

Total solar irradiance changes, though of small magnitude, do appear to affect sea surface temperatures (SSTs), most obviously at latitudes where cloud cover is small and irradiance is abundant, such as the Northern Hemisphere subtropics during summer. The increased SSTs then help intensify circulations spiraling away from the subtropics, again favoring reduced rainfall near the equator and to the south, as well as northern mid-latitudes. Hence, both the UV and TSI forcings produce similar effects, with the latter helping to sharpen the response.

SSTs however have been influenced by other forcings, such as greenhouse gases, over the last few decades, and these transient changes will obviously affect the solar cycle influence. Similarly, increased carbon dioxide in the stratosphere has led to gradual cooling conditions, which affects the UV influence on the stratospheric circulation. So while the solar influence may have produced a broadly similar hydrologic response for many centuries, it now competes with potentially stronger perturbations. Its effect may well decrease with time.

Reference

Rind, D., J. L. Lean, J. Lerner, P. Lonergan, and A. Leboissetier, 2008: Exploring the stratospheric/tropospheric response to solar forcing. J. Geophys. Res., 113, D24103, doi:10.1029/2008JD010114.

Contact

Please address all inquiries about this research to Dr. David Rind.

Response to an Integral Fast Reactor (IFR) critique

As noted in my previous post on Integral Fast Reactors (IFR), Jim Green, from Friends of the Earth (FoE), has posted a critique of IFR.

Below, I (and others, names in square brackets), respond to his major points (in green): [BWB] = Barry W Brook, [TB] = Tom Blees, [GS] = George Stanford, [GLRC] = GLR Cowan. Furthermore, all of these arguments are also answered, in a variety of different ways, here, here, here, here and here. And of course in the book, Prescription for the Planet. So really, you could say that the below are just a small selection of the breadth of answers that are available to the interested reader.

As an aside, I note that I’ve now twice linked to the FoE critique, so as to make readers aware that such critiques exist and to encourage people to read these and judge for themselves. I would hope that the FoE site similarly has the openness, and desire for balance, to link back to this rejoinder.

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What are IFRs? * non-existent reactors proposed to be fuelled by a metallic alloy of uranium and plutonium

[BWB] IFRs are sodium-cooled fast spectrum nuclear power stations with on-site pyroprocessing to recycle spent fuel. Fast spectrum power reactors exist — they are not some mythical ‘future tech’ like fusion reactors. Indeed, even sodium-cooled fast reactors (a type of Advanced Liquid Metal Reactor, ALMR), the type an IFR facility would likely use, already exist (others include lead- or gas-cooled). Metallic alloy fuels (uranium-plutonium-zirconium), operating within a reactor, existed, in the Experimental Breeder Reactor II  at the Argonne National Laboratory. Just because they are not currently used in any operating nuclear power plant doesn’t mean they don’t (haven’t) existed. The only thing that doesn’t currently exist is the full systems design of the integrated IFR plant.

[GS] “Integral” refers to the fact that the fuel processing facility can be an integral part of the IFR plant.

…one or another largely undeveloped form of reprocessing/partitioning to separate transuranics (including plutonium) and actinides (long-lived waste)

[BWB] Transuranics are actinides — they are not separate things as the above implies. The process of pyroproccesing has already gone through significant technical development, but not commercial-scale demonstration. An excellent, colour-illustrated summary, from Scientific American magazine, is available (free download) here.

[GS] Transuranics are the elements beyond uranium – that is, their atomic number is 93 or greater: neptunium, plutonium, americium, curium and more. All of them are man-made elements, since they are so radioactive that the naturally created ones have long since decayed away in our little bit of the universe. They are also called higher actinides… An IFR plant will be a “sink” for plutonium: plutonium to be disposed of is shipped in, and there it is consumed, with on-site recycling as needed. Only trace amounts ever come out.

[TB] Yes, there will be more (unseparated) Pu involved in the entire process but once inside the door of the IFR it will never leave. With the sort of security and operational framework I propose in my book, it would be far easier to obtain Pu from another source such as a small research reactor. The bottom line is that while the IFR will be more proliferation-resistant than other designs, any time fissile material is used there should be some sort of oversight, even at small research reactors such as those found in many universities around the world. It would be far easier to produce isotopically favorable (for weapons) plutonium at one of them than to extract it from the fuel cycle at an IFR.

1. IFR fails the crucial weapons proliferation test. Anything that involves separating plutonium from spent fuel (even if Pu deliberately contaminated with unwanted radionuclides) increases the proliferation risks relative to leaving Pu in spent fuel… [and from a quoted reference] some elements of the technology still remain to be developed and demonstrated… The assessment of this fuel cycle should be an ongoing analysis that keeps up with the research rather than one based on the presumptions of either the advocates or the critics

[BWB] If you deploy IFRs in countries first in nuclear club countries — those that already possess, or are capable of making, nuclear weapons, then there is no additional proliferation risk. These countries already have a nuclear arsenal sufficient to wipe out humanity a few hundred times over. Building new IFR plants cannot meaningfully heighten this risk unless they are constructed in countries with no such capability. If this is done, it would require strong international oversight, as has been discussed elsewhere. Indeed, I’d argue that in consuming existing weapons-grade plutonium, the net effect of more IFRs is to lessen the overall risk of nuclear explosions.

But even without an international oversight organisions, we can reduce >95% of global greenhouse gas emissions by: (a) replacing electricity and transport energy with electricity from zero-carbon sources like IFR, deployed only in nuclear club countries, (b) halting deforestation in all countries (nuclear club and other), (c) massively scaling back agricultural emissions from fuel and ruminant/fertilizer sources, (d) providing non-nuclear-club countries with nuclear batteries, power via cross-border transmission lines,  and boron or other metal fuels for vehicles,  from IFR countries, (e) resolve the municipal solid was problem in all countries via plasma burners.

[GLRC] One can reduce the theoretical potential for power reactors to be involved in proliferation, but their actual history of involvement is zero, and so not subject to reduction. This potential remain like that of car engines to be made into multibarrel cannons: it could happen, and guns do proliferate, but never that way.

[TB] Pray tell, what is the problem with McFarlane’s statement: “The reactor … could be used for excess plutonium consumption or as a breeder if needed …” The fact that it can be used as a breeder is precisely why it would allow us to stop uranium mining, and the fact that it consumes excess plutonium is exactly what we want to do: get rid of separated plutonium and not separate it anymore.

[GS] A breeder is a reactor that is configured so as to produce more fissile material than it consumes. A fast reactor can be designed and operated to be either a net breeder or a net burner. A thermal reactor is a net burner of nuclear fuel, but – and this is very important – all thermal reactors are prolific breeders of plutonium. People often insist on calling IFRs breeders (originally, fast reactors were investigated because of their potential to breed), partly because of genuine confusion, and partly for the emotional impact, since “breeder” carries the subliminal connotation of runaway plutonium production. The central fact that those people are missing is that with IFRs you can choose not to breed plutonium, whereas with thermal reactors you make plutonium whether you want it or not.

- it is axiomatic that spent fuel provides a greater proliferation barrier than the proposed IFR mix of plutonium/actinides/fission products(?) since all those materials are in spent fuel along with other nasties.
- most importantly, none of the above makes a jot of difference if the proliferator has the capacity to further purify the plutonium in a reprocessing plant or a smaller ‘hot cell’ facility (which abound)

None of the above makes a jot of difference if the proliferator produces high-purity plutonium in the first place and if IFR is used as a plutonium breeder rather than a burner … no technical problems whatsoever using IFR to do just that (and the same applies to conventional reactors). So the WMD proliferation potential of IFR reactors (and conventional reactors) must weigh very heavily against them in any comparative assessment of energy options.

[TB] Green’s axiom is nothing of the sort. Spent LWR (light water reactor) fuel can be put through a PUREX (plutonium uranium extraction) process to extract virtually pure plutonium, though its isotopic composition will be far less than ideal for weapons. IFR fuel, on either end of the recycling process, would likewise have to be put through the PUREX process. Neither type of fuel can be handled without special remote handling equipment. So how does that make it axiomatic that spent fuel is a greater proliferation barrier?

In point of fact, anyone hoping to make a bomb from plutonium will likely try to obtain an isotopically more pure plutonium by creating it from U-238 (depleted uranium) at a small research reactor. To a great extent the proliferation threat of power reactors is overblown in light of this, but nevertheless proliferation resistance should always be a priority whenever fissile material is in circulation.

Green’s warning about IFRs being more dangerous in this regard is incorrect, since LWRs produce plutonium as well, and it’s in their spent fuel. Either way you need a PUREX process to extract the (isotopically inferior) plutonium. This whole issue is one of the most common misconceptions about the IFR system, and one of many under which Mr. Green is laboring.

I discuss at length in Prescription for the Planet how and where IFRs would be deployed in order to minimize proliferation risks.

As for breeding high-quality (I assume Green means weapons-grade) plutonium, virtually any reactor (including research reactors) can do that by wrapping a U-238 blanket around the core and letting it get bombarded with neutrons for a while, then removing it and extracting the Pu with the PUREX method. It requires relatively brief exposure, which is NOT what one would have in a reactor core operated for power purposes. Again, as I’ve pointed out here and in my book, fissile material should all be subject to rigorous international oversight. In P4TP I deal with just how to do that in some detail.

[GS] If their IFR plants were safeguarded, the material in the processing stream would be highly undesirable  and their chances of diverting it undetected would be slim indeed. If not safeguarded, they could do what they could do with any other reactor — operate it on a special cycle to produce good quality weapons material. But in either case, most likely they would do what everyone else has done: construct a special production facility. Detecting such a clandestine facility is probably the main, immediate challenge facing international safeguards, and has nothing to do with whether a country has IFRs or LWRs.

2. They don’t exist. Long history of theoretically attractive reactors / fuel cycles which either haven’t been developed or have been highly problematic (e.g. breeders).

[BWB] See above for a comment showing that they (ALMR, pyroprocessing) do exist. Just saying they are fairytales won’t make the reality of them go away.

[GS] The problems with fast reactors (‘breeders’) have been non-fundamental. Examples:
– The Monju reactor was undamaged by the fire (rated 1 on a scale of 0 to 7, with 7 being the most serious accident), and has been kept shut down for political reasons. I think it has been given the go-ahead to start up.
– The EBR-II fast reactor worked flawlessly for many years.
– The Phenix fast reactor in France has been on-line for decades.
– The Superphenix reactor was shut down for political reasons, after it finally had its problems behind it and was working well.
– The Russian BN-600 has been working well for decades.

3. IFR envisages transmutation (bombarding some of the more problemtatic long-lived waste radionuclides to convert them to less problematic, shorter lived radionuclides) but this is problematic because i) it involves the proliferation risks associated with one or another form of reprocessing/partitioning of spent fuel into different streams (and thus facilitating plutonium separation, even if that is not envisaged during routine operations) and ii) the technology has been explored for decades but is still a long way from being mature.

[BWB] For answer to the proliferation risks, see above. Regarding the possiblity of reprocessing to purify plutonium:

“The diversion of nuclear fuel for the purpose of making bombs has been a concern, although presently the handling and destruction of nuclear weapons material is the primary issue. In the IFR, the nature of the fuel reprocessing is such that the fuel remains highly radioactive at all times. Fuel can only be handled in shielded cells or transported in casks weighing many tons. In addition, because the fuel recycle facility is located on-site, there is no transportation of nuclear which could create an opportunity for diversion. In any event, IFR fuel is not suitable for weapons without extensive processing in very expensive facilities. The potential also exists for the IFR to use weapons material for fuel, thus eliminating it, while producing electricity.”

[GS] Near-term, the IFR makes PUREX illegitimate and plutonium inaccessible. Long term, it relieves future generations of the responsibility to guard the plutonium mines, and of the risks of not guarding them adequately.

4. Safety risks associated with use of sodium coolant.

[BWB] The liquid sodium would be housed in a reactor pool with an inert argon overtopping atmosphere. The room in which the secondary sodium loop exchanged heat with the water loop would also be housed in an argon-filled room – a room separate to the reactor (see below Appendix for more information).

[GS] ALMRs use liquid sodium for cooling and heat transfer, which makes the system intrinsically safer than one that uses water. That is because the molten sodium runs at atmospheric pressure, which means that there is no internal pressure to cause the type of accident that has to be carefully designed against in an LWR: a massive pipe rupture followed by “blowdown” of the coolant. Also, sodium is not corrosive (on steel) like water is. Sodium can burn in air and react violently with water, and this of course requires prudent design, involving inert atmospheres and multiple barriers.

5. Brook says IFR will produce “very cheap” power. Good historical reasons to ignore such claims.

[BWB] I searched back through all my written material and comments, and cannot find where I said the quoted phrase ‘very cheap’. Regarding cost though, the standardised-design, factory-built, modular S-PRISM, is likely to be cost competitive or better than current generation nuclear power. I will detail this in a later post. The “good historical reasons” claim just doesn’t wash – there are good historical reasons to believe that renewables will never make up more than a small fraction of our total power generating capacity, but that’s hardly an argument against future expansion.

Further, from the UC Berkley FAQ:

“For a new power source to be viable, the cost of power must be competitive with today’s power systems. The proof of costs in any project only comes when full- sized systems are built and operated. Although no full-sized IFR plant has been built, several facts suggest that the IFR will be very economic. Costs of today’s nuclear plants are just slightly above that of coal as a national average. Several nuclear plants have operated with costs significantly below that of coal however. A new IFR should cost less than either a new nuclear (typical of today’s technology) or coal plant based on the following. The IFR does not require some of the complex systems that today’s reactors require. Examples include the low level radwaste cleanup station, the emergency core cooling system, and fewer control rod drives and control rods for comparable power. Because of the low pressure in the sodium systems, less steel is required for the plant piping and reactor vessel. There are studies that suggest that the reactor containment will be less massive. Other cost savings will be made because the IFR does not require the services of the Isotopic Separation Plants for fuel enrichment. Additional costs to the IFR include the integral fuel reprocessing capability, and a secondary sodium system (but the IFR fuel process costs are somewhat offset by the extremely low cost for raw fuel and the improved waste product). Some studies have been done which indicate that an IFR would be very economical and competitive to build, own, and operate, but the final proof of economics can only come in the construction and operation of a commercial sized plant.”

6. Ignoring the potential for renewables to produce baseload, intermediate- and peak-load power (see Mark Diesendorf’s paper on this topic at www.energyscience.org.au. Also ignoring the fact that 70-80+% of greenhouse emissions arise from sectors other than electricity generation – so Kirsch’s claim that IFR’s could be the “holy grail in the fight against global warming” is stupid.

[TB] Almost 80% of greenhouse gas emissions come from nuclear-capable countries anyway, so even if we just deployed them there we could make tremendous strides, though it would still be wise to create some sort of international oversight organization as I propose in the book.

[BWB] This is at best grossly disingenuous (not to mention insulting to call Kirsch stupid). You need to solve the electricity carbon problem to fix the vehicular fuels problem, space heating and embedded energy in building and manufactured goods, and Tom has a solution for MSW [municipal solid waste] also. About half of agricultural emissions can also be solved if you have a zero-carbon energy source. Then you just need to worry about the ruminant methane and carbon from deforestation. But the bottom line is, if you fix electricity, every else will quicktly start to fall into place.

If we don’t stop coal in places like China and India, we’re hosed, irrespective of what we might do in the US and Oz (and even if we could do with without advanced nuclear, which we very likely cannot). I do wonder, what is Jim Green’s plan is for replacing the 484 GW of coal-fired power stations already installed in China, and the further 200 or so plants in the planning or construction pipeline?

7. Still produces radioactive waste – albeit (in theory) a more manageable waste stream than conventional reactors. But to lessen the long-term hazards, the short-term public health, environmental and proliferation risks are increased through reprocessing, plutonium recycling etc. [Then cites MIT study, concerning how recycling transuranics will cost more than a once-through cycle]

[BWB] A 1 GW IFR power station would produced about 1 tonne of fission products a year. For comparison, a 1 GW coal-fired power station produces over 1 million tonnes. Plutonium (and other actinides) are indeed recycled in pyroprocessing, but Pu is never purified in an IFR, and would never leave the plant facility. Only the vitrified fission products would, which of course cannot be used in any nuclear explosive.

From the FAQ:

“Discussions on waste, nearly unlimited fuel supply, transportation, and a nearly diversion-proof fuel all hinge on the fuel type and the fuel reprocessing scheme. To describe the waste advantages, fuel reprocessing will first be described. Reprocessing of fuel is a key requirement of the IFR. However, IFR reprocessing is very different from processes which have been proposed or which are in use in other countries. Basically, reprocessing IFR fuel consists of two simple steps: 1. fission fragments are removed from the fuel, and 2. unused fuel is recovered, along with the transuranic elements (sometimes called actinides). Normally, the transuranic elements would go to the waste stream with the fission products, but in the IFR, they are kept with the fuel and sent back to the reactor to also serve as fuel. In the above description, note that the waste stream consists of only the fission products. The result is that instead of a waste that remains radioactive for many thousands of years, as would be the case if the transuranic elements were present, the radioactivity in the waste will decay to a value less than that of the original uranium ore in about 200 years. An additional advantage to the waste side of the IFR operation is that the IFR plant produces less low-level waste than today’s nuclear plants. The sodium coolant used in the IFR does not corrode the piping or structure, and, as a result, there are no radioactive corrosion products to remove from the primary system and send to a low-level radioactive waste repository. The fission product waste from an IFR type plant will amount to about 1700 pounds of waste per year for a plant of about 1000 megawatts electric output. This is in contrast to the waste from an equivalent coal plant of about 1,275,000 tons per year. These figures are for a plant that operates about 70 percent of the year.“

[TB] As for the MIT study that Green admiringly quotes, please refer to my book (pg 155–165) for a thorough trashing of same.

8. Brook says IFR reactors would be “safe from melt down” which is nonsense because technologies fail, well-intentioned humans err, and because the best laid plans can go awry if reactors are subject to sabotage or outside attack…

[BWB] The laws of physics say that this is not nonsense. For instance, the metal fuel pins’ composition is such that if they begin to overheat, the resulting expansion decreases their density to the point where the fission reaction simply shuts down.  This is not speculation — it’s been tested and verified. I quote:

“The IFR gains safety advantages through a combination of metal fuel (an alloy of uranium, plutonium, and zirconium), and sodium cooling. By providing a fuel which readily conducts heat from the fuel to the coolant, and which operates at relatively low temperatures, the IFR takes maximum advantage of expansion of the coolant, fuel, and structure during off-normal events which increase temperatures. The expansion of the fuel and structure in an off-normal situation causes the system to shut down even without human operator intervention. In April of 1986, two special tests were performed on the Experimental Breeder Reactor II (EBR-II), in which the main primary cooling pumps were shut off with the reactor at full power (62.5 Megawatts, thermal) – By not allowing the normal shutdown systems to interfere, the reactor power dropped to near zero within about 300 seconds. No damage to the fuel or the reactor resulted. This test demonstrated that even with a loss of all electrical power and the capability to shut down the reactor using the normal systems, the reactor will simply shut down without danger or damage. The same day, this demonstration was followed by another important test. With the reactor again at full power, flow in the secondary cooling system was stopped. This test caused the temperature to increase, since there was nowhere for the reactor heat to go. As the primary (reactor) cooling system became hotter, the fuel, sodium coolant, and structure expanded, and the reactor shut down. This test showed that an IFR type reactor will shut down using inherent features such as thermal expansion, even if the ability to remove heat from the primary cooling system is lost. Events such as the loss of water to the steam system would cause a condition such as the test demonstrated. Another major feature of the IFR concept is that the reactor uses a coolant, sodium, which does not boil during normal operation nor even in overpower transients such as described above. This means that the coolant is not under significant pressure. When coolant is not under pressure, the reactor can be placed in a “pool” of coolant, contained in a double tank, so that there is no real possibility for a loss of coolant. Even if the normal pumps are lost, some coolant flow through the reactor occurs due to natural convection. The features described above allow for greater simplification of a nuclear plant, resulting in cost savings, greater ease in operation, and a safety system that relies on natural phenomenon that cannot be defeated by human error. “

[TB] Arguing that these reactors cannot be safe from meltdowns flies in the face of the laws of physics, which assure that very feature. Regarding terrorist attack, we can secure our airports chemical plants, etc, with not a lot of work, you can design these plants to be virtually impregnable by terrorists (e.g., burying the reactor building).

The new Gen III LWRs, though, are so far advanced as to merit their designation as a different generation. The probabilistic risk assessment of the ESBWR is astronomical, one core melt accident every 29 million reactor-years. Since we don’t have enough nuclear waste to load new IFRs quickly enough to meet the 2050 goal of zero emissions, the newest LWRs could be built to fill any gap that renewables and IFRs couldn’t fill and can be expected to perform safely. Their safety features are far beyond our current reactors by orders of magnitude.

Easy to make wild claims about non-existent reactors since such claims cannot be tested or disproved. As a nuclear industry representative has noted about non-existent reactor types: “We know that the paper-moderated, ink-cooled reactor is the safest of all. All kinds of unexpected problems may occur after a project has been launched.”

[TB] The assertion that such reactors don’t exist with the implication that they’re just fantasies on paper is bunk. BN-350 was operational for years starting in 1972. Phenix went online in 1973 and is still running. BN-600, still running and the most reliable nuclear reactor in Russia’s system. EBR-II ran for 30 years, FFTF at Hanford for many years too (I don’t recall exactly how many at the moment). Can’t make the fuel? They made thousands of fuel slugs at Argonne Labs over the years. Note the dates: 1972, 1973! And people say that something the French and Soviets built 36 years ago should take another 36 years for us to try? By the way, we will need plenty of desalination plants as our population continues to grow toward 9-10 billion. We don’t have 36 years to drag our feet.

Australian nuclear engineer Tony Wood notes that probabilistic risk assessment failed to anticipate the world’s worst reactor accident (Chernobyl) and the worst reactor accidents in the UK (Windscale) and the USA (Three Mile Island)… probabilistic risk assessment failed to anticipate the world’s worst reactor accident (Chernobyl)

[TB] While I seriously doubt that Green has access to such assessments about Chernobyl, our physicists in the USA made a conscious decision years earlier never to build a reactor designed like that because it was way too dangerous. Chernobyl was an accident waiting to happen. It has absolutely nothing to do with IFRs other than as a way to create a false equivalency and scare people.

[GLRC] Melting and blowing up are different, and no power station reactor built in any country that respected the advice Hungarian emigre Dr. Edward Teller gave in 1950 has ever built a reactor that had any way of blowing up. Chernobyl was a reactor explosion, not merely a meltdown. The chance of such an event in any Teller-compliant reactor is, as it has been since 1950, identically zero. (Parked cars are much heavier than parked bicycles or motorbikes, but their toppling-over risk is similarly not more, not the same, and not reduced by some factor; it is zero.)

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NOTE: The above is a working draft only. I will update this post template as further relevant comments (including those posted below) come to hand. Please feel free to make suggestions below, or to email them to me.

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Appendix

Critique of Chapter 6, “Generation IV Nuclear Reactors“, pg 115-130 in: Caldicott, H. (2006) Nuclear Power Is Not the Answer to Global Warming or Anything Else. Melbourne University Press. [Ch6 had input from Dr David Lochbaum]

By Tom Blees

P.122-3: Doesn’t differentiate between aqueous (MOX) and non-aqueous (pyroprocessing of metal fuel) reprocessing. You can’t conflate the two, they are very different.

P.123, last paragraph: breeders ARE fast reactors, just with a different fuel configuration to allow breeding of new fuel.

P.124: The design of the PRISM reactor makes it functionally impossible to lose coolant, and there is neither water nor air surrounding its containment, but rather argon. There no egress below the level of the top of the reactor containment and with argon being heavier than air it’s there for the duration. The steam generator/heat exchanger is in a separate structure. The excursion events described here, with the ominous warning of a deadly radioactive cloud, are generically tossed out there with no consideration for whether they apply to any particular design of Gen IV reactor, and certainly not to the PRISM reactor, which has already gotten its preliminary seal of safety approval from the NRC with probabilistic risk assessments that exponentially exceed the safety of ANY other reactor design.

P. 125: “‘Closing’ the nuclear fuel cycle obviously will contribute to nuclear weapons proliferation.” What kind of ridiculous statement is that? What makes that obvious? Again, MOX and pyroprocessing are conflated, resulting in an “I’ll say anything I want and let the reader assume it applies to everything,” which of course is complete malarkey.

P. 126: 600 years is a stretch for strontium and cesium, which have about 30-year half-lives. Realistically it’s about half that. As for cost, a baseless assertion is made that fast reactors are twice as expensive as LWRs…”extraordinarily expensive,” in fact. Just look at the tone, how scare words are constantly interjected, as in “deadly fission products…deadly…dangerous.” And then comes the derision of the idea that these reactors are “sustainable,” when in fact the fuel is essentially limitless.

P. 126, last paragraph: Notice they forgot to put the word “Some” at the beginning of that paragraph.

Lochbaum’s testimony on P. 127:

– Why is it inappropriate to talk about Gen IV reactors before we dispose of all the waste, when Gen IV reactors would themselves dispose of it?

– One place Lochbaum and I can agree, that the NRC should be reformed. They should also be better funded so they can get their job done instead of operating on a shoestring.

– Again, all Gen IV designs are conflated here, convenient to Lochbaum’s purposes. His second sentence here absolutely does not apply to the PRISM reactor in any way whatsoever. His recommendation that new and untested materials, etc be tested in labs first is a ridiculous “Well, of course!” statement if ever there was one. Where does he think they develop these things?

Continuing his points on P. 128:

– Here he trots out the sodium volatility bogeyman, plus the misleading phrase “releases large quantities of radioisotopes.” Where are they released? They aren’t. And he talks about how the reprocessing involves the processing, transport, and storage of huge quantities of plutonium. Is he here conflating MOX and PUREX reprocessing with pyroprocessing? The latter, of course, never separates out plutonium and doesn’t require any transport of fuel except within the confines of the power plant.

– Again, conflation of MOX and pyroprocessing

– More griping about the Price-Anderson act, which automatically insures all reactors. He talks as if he expects private utility companies to waive coverage if they have safe plants, and that failing to do so (what businessman would?) betrays their dangerousness. I know there’s some Latin term for this, it’s a bit like a Post Hoc or maybe just an inductive fallacy. Pretty transparent, though, isn’t it?

P. 129: I won’t comment on the proliferation potential presented here because I think we need a better system anyway, which I propose in my book. As for the last paragraph, it’s more baseless assertions masquerading as facts.

Mercifully, P. 130: Having proved by unsupported assertion that reactors can’t be built soon enough to affect global warming, Caldicott/Lochbaum uses that “fact” to argue that it would be a grievous misallocation of scarce funds to put any money into nuclear, and just for good measure trots out the old saw about how the nuclear fuel cycle adds to global warming, which for IFRs is less true by far than it is of wind or solar construction projects since neither mining nor enrichment are necessary and nuke plants use 10-40 times less concrete and steel as comparable MW of wind turbine construction.

When finishing off, quoting Greenpeace, all Gen IV designs and intentions are again conflated.

Carbon tax or cap-and-trade? The debate we never had

Guest Post by Tim Kelly. Tim is works as a Principal Climate Change Advisor in the Water Industry.

The Federal Government has now released its Carbon Pollution Reduction Scheme White Paper and as expected the mechanism it has chosen is that of a pollution permit and trade system (cap and trade).  The cap and trade approach has been widely accepted by many businesses, green groups and Australia’s major political parties including the Australian Greens, and yet I am continuously witnessing surprise by individuals and groups when they learn more about the impact of such an approach on eliminating the economy wide benefits of voluntary behaviour.

At the outset, when State and Federal Governments were considering which approach would best deliver National emissions reductions, they should have explained the basic advantages and disadvantages of the two likely contenders, being a carbon emissions tax (carbon tax) or the cap and trade approach, in an open and transparent manner.  At the end of this post I provide a ‘pros and cons’ table comparing these two alternatives. In particular, I note that in the disadvantages column of a cap and trade scheme, stakeholders should have been advised of the following critical points:

1. A cap and trade scheme, by its nature, extinguishes the impact of voluntary efforts from reducing aggregated economy wide emissions as any greenhouse reduction or avoided emission by an individual or entity, because it merely results in freeing up permits to pollute in another part of the economy (i.e., it makes no difference whether I ride my bicycle to work or buy the biggest worst performing V8 petrol vehicle — national emissions will be the same!).

2. A cap and trade system, by its nature, does not drive innovation in voluntary markets, and greatly reduces diversity in voluntary markets.

3. A cap and trade scheme that uses the voluntary surrender of permits as a greenhouse reduction mechanism, ties the cost of voluntary abatement with the cost of pollution, thereby diminishing prospects of continued voluntary action.

This is not to suggest that the cap and trade approach might not drive actions to reduce emissions by permit holders.  But it leaves out vast numbers of individuals and small to medium businesses in the economy from being able to contribute to reduce national emissions in a meaningful way.  A cap and trade approach largely alienates non-permit holding businesses and individuals from taking a meaningful role in reducing the nation’s emissions.  So there is a question as to whether there is any value in the Department of Climate Change slogan “Think climate. Think change. We can’t afford not to”.

Anyway, below is a comparison of the two main approaches focussing on the mechanisms, their effectiveness and flexibility to reduce emissions for a given target.  Naturally, this appears superficial in the table, so if you don’t agree, please consider my full discussion and reasoning (PDF document) which led to my conclusions.

[Barry Brook: This post from Tim is particularly timely, because the Federal Government has just announced an inquiry into the merits of their cap-and-trape model. For instance, a Canberra Times article says:

"The Federal Government's plan to reduce Australia's carbon emissions will be re-examined after Treasurer Wayne Swan referred the emissions trading scheme to the House economics committee. It will examine whether carbon trading is the best way to reduce emissions, while maintaining low economic costs, putting in place long-term incentives for clean energy and contributing to a solution for climate change".

So we may yet have a chance to fix this deeply flawed approach before its gets locked into legislation].

Aspect	Cap and trade	Carbon tax	Winner
Cost on business and community	For a given price on emissions the cost on carbon is has no influence for change in the broader economy (beyond businesses covered by the scheme), other than to become more efficient.	The cost on emissions has a wider impact than just the covered emitters as the tax drives the broader community and smaller businesses to seek alternative low emission electricity, products and services that can reduce National emissions	Tax
Economy wide and community wide involvement	Destroys the ability for an individual or business entity from reducing economy wide impacts.	Drives action directly through emitters and in secondary voluntary markets as people use their choices to avoid the cost and contribute to national emissions reduction	Tax
Simplicity and bureaucracy cost	Terrible, complex documents, complex schemes, complex shifting of funds and compensation for little value, legal risks	MinimalCan be managed to charge only what is required to cause change, letting the market decide where the change would occur without the merry go round.	Tax
Encouraging innovation in the market	Rules out many offset products and as proposed, destroys the integrity of voluntary purchases of renewable energy	Drives innovation and a full suite of low emissions solutions and renewable energy solutions that can be led by market choice for genuine renewable energy	Tax
Need for non tangible offset frameworks.	Creates perverse outcomes and the need for intangible concepts such as using permits as carbon offsets which do not directly link to low emissions solutions and may not indirectly drive low emission solutions and may not even cause economy wide reductions.	No need for weird reverse logic intangible offset concepts using permits to pollute as tangible market offset products and renewable energy choices would work to lower economy wide emissions.	Tax
Price certainty	Requires massive free permit allocations to indirectly manage the permit price. Falls back on a carbon tax to ensure the price stays below $40 even with many emitters paying nothing like this when grandfathered permits are factored in	Easily assigned and controlled by Government.Easily adjusted with new science and negotiations at regular intervals at markets transition.	Tax
Need for full information	Requires complex assessment of current emissions and forecasting of future emissions in five year blocks to seek to minimise over-allocation that would constrain progress or under-allocation that would cause mechanism failure and the need for review and intervention	Not required as the price becomes a constant driver in the economy throughout economic cycles	Tax
Certainty in achieving the greenhouse reduction objective	Unclear as to whether the CPRS could achieve certainty due to its compromises, measurement methodologies and the ability for Government to issue unlimited permits in a given year	Reduces emissions without direct control and necessarily requires reviews as the economy transitions to lower emissions and updates with science and negotiation.	Neither approach provides absolute certainty
Creating a difference between pollution costs and abatement for customers to decide on what products and services they would buy.	Buying and surrendering CPRS permits to reduce emissions causes Siamese twinning, locking the cost of abatement with the cost of pollution. (ultimately all other offsets form national and international sources would cease where all nations adopt cap and trade)	Increases the cost of polluting technologies and provides a relative benefit for other technologies to compete more fairly, letting the market decide what type of electricity, offsets and efficiencies they buy, knowing that these will reduce National emissions	Tax
International linking	Reduces options for trading offsets and low emission products	Increases opportunities to trade in offsets and low emission products	Tax

Integral Fast Reactors for the masses

There was both interest and confusion over at the ABC Unleashed site when I wrote my first piece there on nuclear power. Going by the comments, most folks who were traditionally anti-nuclear continued to harbour their old beliefs and misconceptions about the technologies involved, even after reading my short piece. I did briefly (in one paragraph) explain the advantages of advanced nuclear power (Gen IV, the exemplar being the Integral Fast Reactor) — that is, it eliminates or at least minimises the major concerns held against Gen II (Gen III also solves some, but not waste/supply) and carries a bunch of advantages (like a huge amount of concentrated, zero-carbon energy). But that first Op Ed was always meant primarily to get people thinking more broadly about energy solutions — pointing out that mitigating climate change is the crucial end game: if you don’t get this right, everything else is ceases to matter.

Anyway, in order to take the basic idea of IFR to the masses, I wrote a second piece which is focused specifically on this tech (and a little more on Gen III+, which are also attractive as a transition/stop-gap). I’ve reproduced the essay at the end of this post. For regular readers, there is probably nothing new there. On the other hand, it contains almost too much detail for those unfamiliar with the concepts (at least that is what GR says!).

For another popular audience take on it, Steve Kirsch has written a nice piece for a The Mercury News, a Silicon Valley newspaper. It’s called “How a 24-year-old technology can save the planet“. It’s also well worth a read.

Finally, Jim Green from Friends of the Earth, has posted a critique of IFR. Check it out, and see what you think after reading the details of the IFR technology here  and elsewhere (follow those links). As a head’s up, I plan to post a rejoinder to Jim’s critique,  once I clear a few other things off the desk.

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Why old nuclear power is not new

Previously in this forum I have expressed the view that nuclear power will likely play a key role in the world’s future energy mix. My bottom line was this: the climate and energy crises need fixing with extreme urgency, and both require solutions which completely solve their underlying causes. Half measures at best merely help to delay the same eventual result as business-as-usual (and at worst encourage complacency) — saddling future generations with a climatically hostile planet with a scarcity of available energy.

The comments in response to my openness about the nuclear option were not unexpected. In short, five principle objections were mounted against the viability or desirability of nuclear power.

First, uranium supplies are small, such that if the world was wholly powered by nuclear reactors, there would be at most a few decades of energy to use before our resource was exhausted and the power plants would have to shut down. Second, nuclear accidents have happened in the past, and therefore this power-generation technology is inherently dangerous. Third, expansion of nuclear power would axiomatically risk the proliferation of nuclear weapons. Fourth, in taking the short-term nuclear energy option, we would be bequeathing future generations with the legacy of long-lived nuclear waste requiring thousands of years of management. Fifth, large amounts of energy (and possibly greenhouse gases) would be required to mine, mill and enrich uranium, and to construct and later decommission the nuclear power stations themselves.

Cost and embedded energy arguments used against nuclear must be left for another day, because to be addressed fairly, this also requires a critical examination of the costs and embedded energy requirements for the alternative sources (renewables and fossil fuels).

Now all five of the above points have some merit, although their relative importance compared to threat of climate change and the societal disruption caused by critical energy shortages is debatable. The chaos and bitter complaints which stemmed from the power shortages experienced during the current heatwave in southern Australia demonstrate how dependent we are on a secure, reliable energy supply. But to be honest, there is little point in even having a debate on how persuasive these five objections are, because none will be applicable to future nuclear energy generation.

Of the more than 440 commercial nuclear power stations operating worldwide today and supplying 16 per cent of the world’s electricity, almost all are thermal spectrum reactors. These use ordinary water to both slow the neutrons which cause uranium atoms to split (fission) and to carry the heat generated in this controlled chain reaction to a steam turbine to generate electricity. Because of the gradual build-up of fission products (nuclear poisons) in fuel rods over time, we end up getting about 1 per cent of the useable energy out of the uranium, and throw the rest out as that problematic long-lived waste.

Modern reactors are incredibly safe, with physics-based ‘passive’ safety systems requiring no user-operated or mechanical control to shut down the reaction. Indeed, a certification assessment for the ‘Generation III+’ Economic Simplified Boiling Water Reactor (ESBWR) put the risk of a core meltdown as severe as the one which occurred at Three Mile Island (TMI) in 1979 at once every 29 million years. For reference, the TMI incident resulted in no deaths. Similarly, comparing the inherently unsafe Chernobyl reactor design to an ESBWR is a bit like comparing an army revolver to a water gun.

Fast spectrum reactors, also known as ‘Generation IV’, are able to use 99.5 per cent of the energy in uranium. There is enough energy in already-mined uranium and stored plutonium from existing stockpiles to supply all the world’s power needs for over a century before we even need to mine any more uranium. Once we do start mining again, there is enough energy in proven uranium deposits to supply the entire world for at least 50,000 years. Fast reactors can be used to burn all existing reserves of plutonium and the waste stream of the past and present generation of thermal reactors.

The safety features of Gen IV designs, due for instance to the metal alloy fuel used, is superior even to the ESBWR. The nuclear fuel used by fast reactors is fiendishly radioactive and contaminated with various heavy elements (which are all eventually burned up in the power generation process!), making it impossible to divert to a nuclear weapons programme without an expensive, heavily shielded off-site reprocessing facility which would be easily detected by inspectors.

Yet in reality the only nuclear waste material that will ever leave an Integrated Fast Reactor complex (a systems design for power stations which includes on-site reprocessing) are fission products, which decay to background levels of radiation with a few hundred years (not hundreds of millennia), and can be readily stored because they produce so little heat compared to ‘conventional’ nuclear waste.

For further details, I refer you to my review of the book Prescription for the Planet, which discusses the Integral Fast Reactor technology in-depth, as well as ways to transform our vehicle fleet to use zero-emissions metal-powered burners and how to convert our municipal solid waste to plasma.

Business-as-usual projections suggest that at current pace, we may have Gen IV fast spectrum reactors delivering commercial power by 2025 to 2030. Too late, you say! True enough, but these same sort of forward projections resulted in the International Energy Agency recently predicting that non-hydro renewables will go from meeting 1per cent, to 2 per cent, of global energy use. Either option therefore requires radically accelerated research, development and deployment, if it is to make a difference to climate change and energy supply. A project of Manhattan-style proportions (America’s development of the atom bomb, three years after the first controlled chain reaction) or the audacity of the moon-shot vision (12 years from Sputnik to Neil Armstrong’s famous small step), is required.

There is no doubt in my mind that we have the means to ‘fix’ the climate and energy crises, or at least avert the worst consequences, if we have full recognition of the scale and immediacy of the challenges now faced. New generation nuclear power is one possible path to success, and one that all nations should actively support – though certainly not to the exclusion of other zero-carbon energy options such as renewables and efficiencies. So let’s be sure, when rationally considering energy planning, that we are not mired in old-school thinking about exciting new technologies.

Heatwave update and open letter to the PM

Maximum temperature anomalies (differences from the 1971-2000 average) for 7 February 2009

The Australian Bureau of Meteorology (BOM) has released a detailed analysis of the 2009 southern Australian heatwave. Some of the figures presented are staggering, with numerous temperature records smashed. Indeed, a colleague at BOM pointed out just how exceptional this event was:

“Given that this was the hottest day on record on top of the driest start to a year on record on top of the longest driest drought on record on top of the hottest drought on record the implications are clear...

It is clear to me that climate change is now becoming such a strong contributor to these hitherto unimaginable events that the language starts to change from one of “climate change increased the chances of an event” to “without climate change this event could not have occured”.

I couldn’t have said it better. With the shifting climate we are rapidly moving into uncharted territory with unknown return times (but surely already well above what the long-term records might lead us to expect).

My sincere condolences also go out to the people whose family members or friends were killed the shockingly severe bushfires that followed these unprecedented ‘tinderbox’ conditions. I note that BOM will be releasing further updates in due course on the fire weather aspects of the event.

Some particularly interesting snippets from the BOM report, entitled “SPECIAL CLIMATE STATEMENT 17: The exceptional January-February 2009 heatwave in south-eastern Australia“:

On the morning of 29 January, an exceptional event also occurred in the northern suburbs of Adelaide around 3 a.m. when strong north-westerly winds mixed hot air aloft to the surface. At RAAF Edinburgh, the temperature rose to 41.7°C at 3.04 a.m. Such an event appears to be without known precedent in southern Australia…

The January-February 2009 event has now been responsible for seven of the eight highest temperatures on record in Tasmania; a total of eight sites reached 40°C, a mark which had only been reached on 16 previous occasions in the state’s recorded history…

On 7 February (Figure 2), the focus of the most extreme heat, which was accompanied by high winds and very low humidity, was in Victoria. An all-time state record was set at Hopetoun, in the state’s north-west, when the temperature reached 48.8°C, exceeding the old record of 47.2°C, set at Mildura in January 19395 by a considerable margin. Seven other sites, in the Wimmera and in the area immediately west of Melbourne, also exceeded the old record, including Avalon Airport (47.9°C), Horsham (47.6°C), Longerenong (47.6°C) and Laverton (47.5°C). The Hopetoun temperature is also believed to be the highest ever recorded in the world so far south. A total of 14 sites exceeded the previous Victorian February record of 46.7°C…

Many all-time site records were also set in Victoria on 7 February, including Melbourne (154 years of record), where the temperature reached 46.4°C, far exceeding it’s previous all-time record of 45.6°C set on Black Friday (13 January) 1939. It was also a full 3.2°C above the previous February record, set in 1983. Three of Melbourne’s five hottest days have now occurred during this event. Geelong (47.4) and Wilsons Promontory (42.0) were among long-term sites which broke all-time records which had been set only the previous week. In total, of the 31 currently open sites in Victoria with 30 years or more of data which reported on 7 February, 21 set all-time records, five set February records, and only five failed to set records at all. 7 Record high temperatures for February were set over 87% of Victoria…

Both Adelaide and Melbourne set records for the most consecutive days above 43°C. Adelaide’s temperatures were at this level on each of the four days 27-30 January, and Melbourne’s for three days from 28-30 January, breaking the previous records of two at both locations… Adelaide ultimately had nine consecutive days above 35°C; after never having experienced more than eight consecutive days above 35°C before March 2008, it has now happened twice within twelve months…

Melbourne had no measurable rain from 4 January to 7 February, the equal second-longest dry spell on record for the city (35 days). This approaches the record of 40 days set in 1954-55. Melbourne (0.8 mm) had its second-driest January on record, and with only 2.2 mm to 8 February has now experienced its driest start to a year on record…

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Second, Dr Andrew Glikson has written an open letter to the Prime Minister, once again reiterating the urgency of the climate emergency. I have to ask (rhetorically I suppose), what will it take for the politicians to switch modes, from the awfully clichéd ”Climate change is happening, but let’s move slowing in doing anything meaningful about it so as to protect X, Y and Z [insert your favourite short-term political issue]” to the realistic “This is an emergency!”. I dunno. Let’s just hope it doesn’t take too many more disasters, such as this heatwave and its manifold consequences, or the crossing of Earth system tipping points such as the Arctic sea ice loss, to trigger the full-scale ‘war footing’ that is now so desperately required.

OPEN LETTER TO THE PRIME MINISTER OF AUSTRALIA

Dear Hon Kevin Rudd, MP, Prime Minister of Australia

A WARNING FROM THE PAST CLIMATE HISTORY OF EARTH

In his letter to you of 27 March, 2008, Professor James Hansen, leading US climate scientist and chief scientist of NASA’s Goddard Institute of Space Research (http://www.aussmc.org.au/Hansen_letter_to_Rudd.php), wrote, among other:

“Global climate is near critical tipping points that could lead to loss of all summer sea ice in the Arctic with detrimental effects on wildlife, initiation of ice sheet disintegration in West Antarctica and Greenland with progressive, unstoppable global sea level rise, shifting of climatic zones with extermination of many animal and plant species, reduction of freshwater supplies for hundreds of millions of people, and a more intense hydrologic cycle with stronger droughts and forest fires, but also heavier rains and floods, and stronger storms driven by latent heat, including tropical storms, tornados and thunderstorms”

Since this letter was written new research demonstrates the Earth’s atmosphere is more vulnerable to the rise in trace greenhouse gases, which regulate its temperatures, than we wish to believe, and that such rises in the past resulted in extreme shifts in the state of the atmosphere, oceans and biosphere, triggering mass extinction of species. Examples of some of these papers:

http://www.nature.com/nature/journal/v451/n7176/full/nature06588.html

http://www.agu.org/pubs/crossref/2008/2008EO490001.shtml

http://www.sciencemag.org/cgi/content/abstract/1157707v1

http://www.columbia.edu/~jeh1/2008/TargetCO2_20080407.pdf

The new findings indicate that targets considered in the Garnaut Review, namely 450 ppm or 550 ppm CO2, can not be sustained. This is because carbon cycle feedbacks, including looming methane emissions, and the dynamics of ice/warming melt water interactions, threaten runaway warming leading toward tipping points, as occurred repeatedly in the past.

Current atmospheric CO2 levels (387 ppm) are already in the danger zone, while carbon gas emissions proceed at high rates (2.2 ppm in 2007; 1.8 ppm in 2008). It emerges that, unless simultaneous efforts are made to sharply cut carbon emissions and develop the technology for down-draw of atmospheric CO2, the future of our young and future generations looks grim.

The Greenland and Antarctic ice sheets formed under atmospheric conditions at, or below, 450 parts per million, which continued emissions and feedbacks will reach within a couple of decades, leading to temperature increases above 2 degrees C, advanced ice melt and metres-scale sea level rise.

Large mammals can hardly exist on land on an ice-free Earth, nor can human civilization survive such conditions.

In the wake of your election commitment to evidence-based policies (http://www.onlineopinion.com.au/view.asp?article=8049) you were given a historic opportunity to lead the world by example in relation to what you have correctly described as the great moral challenge of our generation (http://www.alp.org.au/labortv/uKTHPU1yia), through conversion of a coal-intensive highest per-capita carbon-emitting economy into an alternative energy-based system.

This could tilt the scales in an increasingly desperate global effort to avert what has been recently described by John Holdren, Obama’s new chief science advisor, as the global climate disruption (http://www.climatesciencewatch.org/index.php/csw/details/holdren_global_climate_disruption/)

Less than one year elapsed since Hansen’s letter was sent, and while isolated weather events are not necessarily related to climate change, a dangerous trend has developed consistent with projections of atmospheric science, relegating southern Australia to droughts and fire and the north to intense cyclones and floods.

Given the gravity of the matter, I suggest you consider to urgently convene a climate summit, where your government can listen to reports of severe climate disruption around the globe and in Australia, and to what the science says regarding future generations your government was entrusted to protect.

Honorable Prime Minister, as communicated by James Hansen, your leadership is required (http://www.aussmc.org.au/ Hansen_letter_to_ Rudd.php). I hope this will happen in the spirit of Dietrich Bonhoeffer (http://www.abc.net.au/rn/ religionreport/stories/ 2006/1755084.htm).

Yours faithfully

(Dr) Andrew Glikson

Earth and paleo-climate scientist

Australian National University

9 February, 2009

How hot should it have really been over the last 5 years?

Fig. 1. Seasonal average global temperature anomaly (TA), normalised sign-inverted southern oscillation index (SOI) and normalised total solar irradiance (TSI), from 1979 to 2008.

Last year, 2008, was about the 9th hottest year in the instrumental record (range: 7th to 10th). It certainly wasn’t the hottest year. That record goes to either 1998 or 2005, depending on which temperature record you look at. NASA’s GISTEMP gives it (slightly) to 2005, whilst the Hadley Centre and the two satellite measures (UAH and RSS) give it to 1998. Note that only GISTEMP averages over the northern polar regions, an area which has warmed more than the planet as a whole due to the retreat of snow and ice (which makes that part of the world duller, and so able to absorb more sunlight).

A question that is often asked by the naive or disingenuous is: “If the buildup of greenhouse gases is causing global warming, then why isn’t each year hotter than the previous?” This is a simplification the more common meme: “Global warming has stopped since 1998” (I note that it ceased being “Earth hasn’t warmed in the last 10 years” when 1998 passed more than a decade into history). The latter question is addressed explicitly in this earlier post — it has to do with the amount of energy transferred from the oceans to the atmosphere, given that most (>95%, on average) of the extra energy being trapped by increased greenhouse gases in going into slowly heating the oceans and melting ice across the planet.

Climate scientists obviously recognise that the Earth’s temperate is influenced by a whole range of forcings and feedbacks. Greenhouse gases, predominantly CO2, is one forcing causing gradual, inexorable warming. Transfer of heat from the oceans to the atmosphere is another and can cause temporary warming or cooling — perhaps the most important being characterised by the El Niño / La Niña oscillation. The solar cycle, lasting an average of 11 years, is yet another. A fourth powerful but occasional influence is large volcanic eruptions which cause temporary dimming (cooling). Global climate models include all of these factors when attempting to reconstruct past temperatures, and can be used to make future predictions of climate if these forcings are specified for future scenarios.

But we don’t need a global climate model to get a rough appreciation of how these forcings affect year-to-year temperature. We can approximate them with some basic correlative analysis that are uncomplicated and straightforward to understand.

Fig. 1 shows three relevant time series. In green is the seasonal average global temperature anomaly (TA), based on the composite measure provided at WoodforTrees. This is useful as it side-steps the ‘debate’ over which of the four major temperature measures is ‘best’ – it uses all of them and corrects for different baselines. Seasons are Dec-Jan-Feb, Mar-Apr-May, Jun-Jul-Aug and Sep-Oct-Nov. In blue is the southern oscillation index (SOI), in this case inverted (so that a higher SOI generally equates with a positive forcing) and normalised to scale between 0 – 1. In red is the satellite measure of total solar irradiance (TSI; similar to sunspot number), originally reported in watts per metre squared but here also normalised to a 0-1 scale so that it can be plotted alongside temperature and the SOI. The SOI and TSI have been offset by 3 months compared to Temperature, because we would expect some lag between the forcing and the response. The period 1979 to 2009 is chosen for two reasons — it is the period covered by all four temperature measures, and it also represents a span of time sufficient to represent ‘climate’ rather than weather — 30 years.

Fig. 2. Actual temperature (green), predicted temperature (blue, based on greenhouse gases, SOI, TSI and volcanic forcing) and temperature trend (grey dashed) with SOI, TSI and volcanic forcing held at its 30-year average.

Visually, it is clear that there is quite a good relationship between the up and down fluctuations of temperature and both SOI and TSI, although the gradual upwards trend in temperature is also apparent. We can quantify this relationship statistically. I fitted a simple linear ANCOVA model with TA as the dependent variable and Time (each season since DJF of 1978-1979), SOI and TSI as continuous predictors and volcanic forcing as a categorical predictor (VOL; a value of 1 is assigned for the few seasons following the 1982 eruption of El Chichon and the 1991 eruption of Pinatubo). I’ve ignored other complicating matters such as tropospheric aerosols. Still, the model is structurally not too bad a fit (for those familiar with the method, the residual model diagnostics confirm a reasonable conformation with assumptions, and 67% of the deviance is explained by the four predictors).

These results are useful. They show a strong positive trend in temperature (+0.0054C per season [or about 0.216C per decade]), a forcing of about +0.4C for a strong El Niño, +0.24C for the peak of solar forcing, and -0.27C for a volcanic event. With this model-based information, we can make two visual additions to the temperature plot. They are show in Fig. 2. First, the original temperature data is plotted in green. In blue is the season temperature as predicted by the ANCOVA model, based on historical forcings. The dashed trendline is the warming trend expected if all other forcings (SOI, TSI and VOL) are held at their 30-year average values.

Of relevance to the title of this post, these correlations can be used to work out (crudely!) what temperatures we might have expected over the last five years based on three different scenarios. First, if SOI, TSI and VOL were all held at their 30-year average, what would the global temperatures have been in 2004, 2005, 2006, 2007 and 2007? (AvF) Also, what if they all been at their minimum (MinF) or maximum (MaxF) 30-year values? These scenario results, along with the composite observed temperature anomalies, is shown in the table below. The last three columns represent deviations from the observed values (so, for example, in 2006 the observed anomaly was +0.69C but if all forcings had been at their 30-year average [AvF] it would have been +0.03C hotter than this, or +0.72C).

These numbers indicate that 2004 and 2007 were right on the average forcing expectation . 2005 was slightly hotter than we’d have expected (it was an moderate El Niño year and near the top of the solar cycle) and almost spot on the MaxF prediction. Conversely 2008 was quite a bit cooler and close to the MinF expectation. Why? It was a La Nina year and the sun had bottomed out in its irradiance/sunspot cycle. If 2008 had been an average year, we should have expected it to be 0.25C hotter, at around +0.75C anomaly.

To cap of this little venture into what-if land, I’ll have a bit of fun and predict what we might expect for 2009. My guess is that the SOI will be neutral (neither El Niño or La Niña), the solar cycle 24 will be at about 20% of its expected 2013 peak), and there will be no large volcanic eruptions. On this basis, 2009 should be about +0.75, or between the 3rd and 5th hottest on record. Should we get a moderate El Niño (not probable, based on current SOI) it could be as high as +0.85C and could then become the hottest on record. I think that’s less likely.

By 2013, however, we’ll be at the top of the solar cycle again, and have added about another +0.1C worth of greenhouse gas temperature forcing and +0.24 of solar forcing compared to 2008. So even if 2013 is a La Niña year, it might still be +0.85C, making it hotter than any year we’ve yet experienced. If it’s a strong El Niño in 2013, it could be +1.2C, putting it way out ahead of 1998 on any metric. Such is the difference between the short-term effect of non-trending forcings (SOI and TSI) and that inexorable warming push the climate system is getting from ongoing accumulation of heat-trapping greenhouse gases.

Is there a link between Adelaide’s heatwave and global warming?

Schematic illustrating the disproportionate effect on extreme and record temperatures when the mean temperature increases, for a normal temperature distribution.

Adelaide is the hot place to be right now. We’re in the middle of an extreme, enduring heatwave, and the city’s residents are suffering. Indeed, we’ve had rolling blackouts as the power system fails to meet peaking loads, and more people are suspected to have died from heat stress over the last week than were killed in the infamous Ash Wednesday bushfires of 1983.

Now, make no mistake, the month of January in Adelaide is renowned for its hot, dry weather. For instance, back in 1908 the city felt the brunt of a run of 6 days above 40C, and in 1939 the temperature soared to its historical single-day record (still unbeaten) of 46.1C. So given this context, an obvious question is whether the current heatwave is anything remarkable, and can a climate change signal be detected in this event? The standard scientific answer I would usually give is something like this: ‘Extreme weather has occurred in the past, and it is not possible to definitively attribute any one unusual event to climate change. That said, a higher frequency of intense heatwaves like this is consistent with the expectations of a rising global temperature‘ (see figure showing ‘more record hot weather’). But in the case of Adelaide’s 2009 heatwave, a bit of deeper investigation does indeed suggest that a climate change link is very likely.

Starting on January 26, we’ve had daily maxima of 36.6C, 43.2C, 45.7C [3rd hottest day ever recorded], 43.4C, 43.1C, 41.1C, 40.6C and 38.8C. This also included the hottest night ever recorded in South Australia, when around midnight on 29th Jan, it dropped to a minimum of 33.9C. For the last 5 days the temperature has not dropped below 25.9C at night. The run of 6 days above 40C equals the record from 101 years ago. The current 5-day forecast is for 38C [update: actual = 36.3C], 38C [33.0C], 37C [35.6C], 40C [43.9C] and 34C [41.5C]; if this holds, we’ll have had a string of 12 days above 35C, or perhaps 13 if Saturday nudges up a degree or so over the forecast. The heatwave is hitting more than Adelaide by the way — Melbourne got its 2nd hottest day on record and Tasmania its hottest ever. The town of Kyancutta on the Eyre Peninsula sizzled at 48.2C.

Historical records from the Bureau of Meteorology show that there have been 6 previous ‘heatwave events’ (here defined as >35C) that lasted 8 days, many more of 7 days, more still of 6, and so on. This is useful information for analysis, because it turns out that the return time of any given string of hot days is logarithmically related to it’s length (see below for how I know this). From Bureau records, we can infer that if the current heatwave does last for 12 days, such an extreme outlier should only occur, by chance (i.e. if the climate is not trending), once every 400 years or so. If it goes for 13 days, then that’s roughly a 1 in 1000 year event — such is the nature of a logarithmic relationship! Statistically speaking, there is always a danger in extrapolating beyond the bounds of your data, but in the case of rarely (or never) observed events, there is little other empirical recourse (a mechanistic simulation such as a general circulation model would also give useful inference on this matter).

So why might I be as bold as to suggest a climate change link with this current heatwave? Well, the hottest night ever recorded is certainly notable, and is consistent with the expectations of a greenhouse gas (GHG) induced warming. You see the basic hypothesis goes that if solar forcing is causing the surface warming, we’d expect there to be relatively more hot days (when the sun is shining) compared to hot nights (when the sun is hitting the other side of the planet and the warmth is maintained by the insulating effect of GHGs and high altitude clouds). If it’s a build-up of GHG that is driving the warming, you’d conversely expect relatively more hot nights, because the ‘atmospheric blanket’ has thickened. Another way to think about this commonsense prediction is to consider deserts, which have few high clouds and so tend to get very cold at night. Or in the extreme, to look to the Moon, which has no GHG at all and so has daily temperatures soaring above 100C and night times plummeting to below -100C! But let’s not read too much into one extremely hot night in Adelaide — it could still just be unusual weather, after all. Better in this case to reflect on large meteorological data sets which quite clearly confirm the GHG prediction, showing that relatively more warming has occurred at night compared to the day time. Another nail in the solar warming idea (but that’s another story).

Adelaide’s record-smashing 15 day March 2008 heatwave

Okay, so if it’s not the hottest night on record that seals the deal in my mind, what is it? Well, it’s another recent heatwave actually — one that occurred only 10 months ago in Adelaide. The record-smashing March 2008 heatwave persisted for a whopping 15 straight days and surpassed the previous longest stretch of above 35C degree temperatures recorded in any Australian capital city (formerly held by Perth in 1988). Poor old Kyancutta took a hot hit then too, recording 13 days straight of over 40C temperatures. The hottest night ever in March in Adelaide, of 30.2C, was also recorded during this event. Overall, last year’s heatwave was not as consistently hot as this year’s event (see chart), but it will still likely hold the record for duration. A frequency analysis on this monster implies that it was a 1 in 3,000 year event in a stationary climate! Read the media release by SARDI to show how Dr Warwick Grace calculated its return time. (Put another way, that’s about as likely as tossing a coin 12 times and getting all heads [or tails] — try it, I dare you…)

Now global warming is quite clearly expected to both increase the frequency of heatwaves (i.e., greater number of events per unit time) and cause those heatwaves that do occur to be hotter and to last longer (on average). This is a fairly simple expectation one derives from a change in the average temperature, as the top figure in this post indicates. The Intergovernmental Panel on Climate Change Fourth Assessment Report (2007) has this to say about it:

“Since 1950, the number of heat waves has increased and widespread increases have occurred in the numbers of warm nights… In several regions of the world, indications of changes in various types of extreme climate events have been found. The extremes are commonly considered to be the values exceeded 1, 5 and 10% of the time (at one extreme) or 90, 95 and 99% of the time (at the other extreme). The warm nights or hot days are those exceeding the 90th percentile of temperature, while cold nights or days are those falling below the 10th percentile… In the last 50 years for the land areas sampled, there has been a significant decrease in the annual occurrence of cold nights and a significant increase in the annual occurrence of warm nights. Decreases in the occurrence of cold days and increases in hot days, while widespread, are generally less marked. The distributions of minimum and maximum temperatures have not only shifted to higher values, consistent with overall warming, but the cold extremes have warmed more than the warm extremes over the last 50 years. More warm extremes imply an increased frequency of heat waves.“

So, in Adelaide we have two freakishly rare extreme events happening with a 10 month period. How likely is that? Well, if the events are totally independent, we’d expect the joint likelihood of two such heatwaves (of 0.25% probability per year [the 2009 event] and 0.033% per year [2008 event], respectively), occurring within the same 12 month period, to happen about once every 1,200,000 years. Is that unlikely enough for you? But if there is ‘autocorrelation’ (dependencies between the two events due to a linked cause — such as climate change), this calculated probability is not valid.

What exactly do I mean by this? Well, the heatwave that struck Europe is 2003 provides a good way to illustrate my final point, thanks to a neat analysis published in Nature in 2004. The authors of this study estimate that warming to date has at least doubled the probability of such an extreme heatwave occurring. Moreover, under ongoing heating, climate models suggest that by 2040, this extraordinarily hot summer (in historical terms) will be just a run-of-the-mill average summer. By 2060, it will be among the coolest of summers the future residents of Europe will thereafter ever experience.

The figure below really says it all. Such is the nature of coping with a ‘gradually warming’ climate…

The European heatwave of 2003 in historical and future context. The black line shows recorded summer temperatures in Europe, with the cross showing the extremely hot summer of 2003. Also shown in various colours are some climate model simulations which match historical records and project ongoing warming under a scenario which includes only a gradual reduction in human-caused greenhouse gases. Climate variability is superimposed on the warming trend, but the impact on extremes is also clear. Following the red dashed line it is clear that by 2040, the anomalously hot summer of 2003 with be merely an average summer. By 2060, it will be positively chilly.

A cooling story involving ozone, the sun and the sea

A note from the author Erl Happ, who is a Western Australian wine maker from Margaret River.  We can learn a lot about the behaviour of the Sun/ Earth system via an examination of historical temperature data. This little essay illustrates that point. It was first published at the blog I share with Carl Wolk at http://climatechange1.wordpress.com/

All data is presented as a 12 month moving average centered on the seventh month. Data sourced from: Kalnay, E. and Coauthors, 1996: The NCEP/NCAR Reanalysis 40-year Project. Bull. Amer. Meteor. Soc., 77, 437-471. at:

http://www.cdc.noaa.gov/cgi-bin/data/timeseries/timeseries1.pl

Figure 1 Response of lower stratosphere to ocean warming

When the tropical sea heats up evaporation is enhanced. Convection tends to carry moisture high up into the tropical atmosphere and some overshoots the tropopause into the stratosphere where it encounters ozone.

Ozone is soluble in water. In the commercial manufacture of ozone the air that is to carry the ozone is cooled to minus 80°C so as to dry it out and make it possible for that air to convey the ozone to the point of application, for example the empty wine barrel to be sanitized.

Ozone is a strong absorber of both UVB from the sun (or we would get more sunburn and more cancer) and also long wave radiation from the earth. The ozone molecule swiftly transfers the extra energy gained to the surrounding air and the temperature of that air increases. If however the ozone content of the air diminishes there is less heat imparted to the air and its temperature falls. So air that contains ozone can fall in temperature from two sources. The first is a reduction in radiation. The second is a reduction in ozone content.

Figure 1 demonstrates that increased evaporation in the tropics is accompanied by a fall in the temperature of the air in the lower stratosphere at 70hPa. This fall in the temperature of the air at 70hPa relates directly to the magnitude of the increase in sea surface temperature. The fall in temperature in the stratosphere at 70hPa is due to loss of ozone into water solution.

How far into the stratosphere does this effect extend?

Figure 2. Response of stratosphere to humidification and solar activity

Figure 2 shows that the fall/rise in the temperature of the air at 70hPa also occurs at 50hPa and 30hPa. This shows that the stratosphere is fairly well mixed, and relatively speedily so, despite the more sluggish convection (than in the troposphere) due to the temperature increase with elevation.

If the temperature of the air in the stratosphere falls as the surface warms (due to the evaporation humidifying the stratosphere) we would expect the temperature of the stratosphere to warm as the surface cools. That indeed is what has happened since 1998. I show the increase in stratospheric temperature with arrows. The increase is due to more ozone in the stratosphere as the tropical ocean has gradually cooled.

Now I want to draw the readers attention to what is going on at 10hPa when the surface warms. After 1978 when the sun became very active and tropical sea surface temperature jumped we can trace the episodic fall in temperature all the way from 70hPa to 10hPa. The paradox is that the micro-structure involves cooling during specific El Nino warming events but the macro-structure shows a general increase in 10hPa temperature due to a secular increase in ozone due to the impact of enhanced ionizing radiation on oxygen. If we examine the data closely we see that prior to 1978 a rise in 70 hPa temperature (due to enhanced ozone as the tropical sea surface episodically cools) is accompanied by a fall in 10hPa temperature due to diminished solar activity (less ionizing short wave radiation). This observation links the sun with surface temperature change.

If the macro-structure at 10hPa shows the impact of ionizing radiation on oxygen we can see from the curve that this particular macro warming event that began in 1978 is not yet over. We have some way to go before 10hPa temperature returns to the 1948 level.

Let’s move right along to an examination of temperature change in the atmosphere since 1948.

Figure 3 Temperature change in the lower troposphere

Figure 3 shows that in general the lower levels in the atmosphere have definitely warmed. Whatever the cause of this warming, and the analysis above suggests that it is entirely due to the sun, the atmosphere above 400 hPa is not storing warmth. Its temperature has not increased at all. Below 700hPa temperatures took off in 1978 and have not yet returned to base level. Above 700 hPa temperatures have returned to base level on many occasions, most recently in the year 2000. Why have temperatures below 700hpa not returned to base? I suggest that it is because these levels are too close to the great earthly store of warmth, the ocean.

In passing we note that the largest increase in temperature is not at the surface but at 850hPa (1 km) where water vapour condenses to form cloud. This is not a ‘greenhouse effect’ but is due to release of latent heat of condensation. The tropics tend to be heat saturated so more energy goes straight into evaporation. Water is the Earth’s refrigerant gas and the troposphere is the engine that drives the refrigeration mechanism.

Figure 4 Temperature change in the upper troposphere

Figure 4 shows the pattern of heating in the upper troposphere. Again we note the lack of any long term increase in temperature. At all levels the temperature has returned to base. However, between 200hPa and 100hpa the period of increased solar activity that is evident in 10hPa temperature in figure 2 manifests as a strong and sustained increase in temperature between the onset in 1978 and demise about 2006.

Those who have followed my discussions with Leif Svalgaard will know that he steadfastly maintains that 200hPa temperature simply reflects surface temperature and that the level of ozone in the troposphere below the tropopause (100hPa) is too slight to produce a thermal response to UVB. He is plainly incorrect. The surface is warmer today than in 1948 but 200hPa temperature is back to 1948 levels. Look again I say?

Above 500hPa the temperature of the air is below freezing point and clouds exist as micro crystalline ice with highly absorptive (infrared) and reflective (visible spectrum) properties. In the period of warming between 1978 and 1999 the ratio of ice cloud to droplet cloud changed because, while humidity fell continuously at all levels evaporation in the tropics and convection kept up the moisture supply to the upper troposphere and, as we have seen, the stratosphere. In this regime ice cloud becomes an ever more important constituent of the Earths armoury against solar radiation. When the temperature of the upper troposphere warms ice cloud evaporates and more sunlight gets to the ocean surface. This is the atmospheric dynamic that drives ENSO.

Take home messages:

1. There is a natural cycle that drives the concentration of ozone in the stratosphere. This is shown by the cooling at 70hPa as the tropical sea warms.
2. The influence of the sun is seen in the micro-structure and the macro-structure of temperature at all levels of the atmosphere above the 200hPa pressure level between 20°N and 20°S.
3. The atmosphere does not store warmth. Above 700hPa it has returned to base temperature after each warming episode between 1948 and 2008. It is the sea that stores warmth.
4. The rate of warming at 850hPa (1 km) is a good measure of the increased energy that the Earth receives from the sun over the course of time. It is here that the temperature has increased most since 1978. Temperature at 850hPa will only return to base when the tropical oceans themselves return to base temperature. This return seems to be in process but rest assured that warming and cooling events will continue to provide a secure topic for everyday conversation.
5. Cooling of the stratosphere is not due to greenhouse gas warming of the troposphere. There is no temperature change in the lower troposphere except very close to the warmer ocean. Cooling of the stratosphere is due to ozone loss associated with surface warming.
6. Ozone loss in the stratosphere is a natural consequence of sea surface warming.

Have you comprehended the argument? Here is a test.

Explain why 10hPa and 100hPa temperatures are in sync under high solar activity and out of sync at low solar activity as seen in figure 5 below.

Figure 5 Temperature change at 10hPa and 100hPa