The past few weeks and years have seen a bushel of papers finding that the natural world, in particular perhaps the ocean, is getting fed up with absorbing our CO2. There are uncertainties and caveats associated with each study, but taken as a whole, they provide convincing evidence that the hypothesized carbon cycle positive feedback has begun.
Of the new carbon released to the atmosphere from fossil fuel combustion and deforestation, some remains in the atmosphere, while some is taken up into the land biosphere (in places other than those which are being cut) and into the ocean. The natural uptake has been taking up more than half of the carbon emission. If changing climate were to cause the natural world to slow down its carbon uptake, or even begin to release carbon, that would exacerbate the climate forcing from fossil fuels: a positive feedback.
The ocean has a tendency to take up more carbon as the CO2 concentration in the air rises, because of Henry’s Law, which states that in equilibrium, more in the air means more dissolved in the water. Stratification of the waters in the ocean, due to warming at the surface for example, tends to oppose CO2 invasion, by slowing the rate of replenishing surface waters by deep waters which haven’t taken up fossil fuel CO2 yet.
The Southern Ocean is an important avenue of carbon invasion into the ocean, because the deep ocean outcrops here. Le Quere et al. [2007] diagnosed the uptake of CO2 into the Southern Ocean using atmospheric CO2 concentration data from a dozen or so sites in the Southern hemisphere. They find that the Southern Ocean has begun to release carbon since about 1990, in contrast to the model predictions that Southern Ocean carbon uptake should be increasing because of the Henry’s Law thing. We have to keep in mind that it is a tricky business to invert the atmospheric CO2 concentration to get sources and sinks. The history of this type of study tells us to wait for independent replication before taking this result to the bank.
Le Quere et al propose that the sluggish Southern Ocean CO2 uptake could be due to a windier Southern Ocean. Here the literature gets complicated. The deep ocean contains high concentrations of CO2, the product of organic carbon degradation (think exhaling fish). The effect of the winds is to open a ventilation channel between the atmosphere and the deep ocean. Stratification, especially some decades from now, would tend to shut down this ventilation channel. The ventilation channel could let the deep ocean carbon out, or it could let atmospheric carbon in, especially in a few decades as the CO2 concentration gets ever higher (Henry’s Law again). I guess it’s fair to say that models are not decisive in their assessment about which of these two factors should be dominating at present. The atmospheric inversion method, once it passes the test of independent replication, would trump model predictions of what ought to be happening, in my book.
A decrease in ocean uptake is more clearly documented in the North Atlantic by Schuster and Watson [2007]. They show surface ocean CO2 measurements from ships of opportunity from the period 1994-1995, and from 2002-2005. Their surface ocean chemistry data is expressed in terms of partial pressure of CO2 that would be in equilibrium with the water. If the pCO2 of the air is higher than the calculated pCO2 of the water for example, then CO2 will be dissolving into the water.
The pCO2 of the air rose by about 15 microatmospheres in that decade. The strongest Henry’s Law scenario would be for the ocean pCO2 to remain constant through that time, so that the air/sea difference would increase by the 15 microatmospheres of the atmospheric rise. Instead what happened is that the pCO2 of the water rose twice as fast as the atmosphere did, by about 30 microatmospheres. The air-sea difference in pCO2 collapsed to zero in the high latitudes, meaning no CO2 uptake at all in a place where the CO2 uptake might be expected to be strongest.
One factor that might be changing the pressure of CO2 coming from the sea surface might be the warming surface waters, because CO2 becomes less soluble as the temperature rises. But that ain’t it, as it turns out. The surface ocean is warming in their data, except for the two most tropical regions, but the amount of warming can only explain a small fraction of the CO2 pressure change. The culprit is not in hand exactly, but is described as some change in ocean circulation, caused maybe by stratification or by the North Atlantic Oscillation, bringing a different crop of water to the surface. At any event, the decrease in ocean uptake in the North Atlantic is convincing. It’s real, all right.
Canadell et al [2007] claim to see the recent sluggishness of natural CO2 uptake in the rate of atmospheric CO2 rise relative to the total rate of CO2 release (from fossil fuels plus land use changes). They construct records of the atmospheric fraction of the total carbon release, and find that it has increased from 0.4 back in about 1960, to 0.45 today. Carbon cycle models (13 of them, from the SRES A2 scenario) also predict that the atmospheric fraction should increase, but not yet. For the time period from 1960 to 2000, the models predict that we would find the opposite of what is observed: a slight decrease in the atmospheric fraction, driven by increasing carbon uptake into the natural world. Positive feedbacks in the real-world carbon cycle seem to be kicking in faster than anticipated, Canadell et al conclude.
There is no real new information in the Canadell et al [2007] analysis on whether the sinking sink is in the ocean or on land. They use an ocean model to do this bookkeeping, but we have just seen how hard it is to model or even understand some of the observed changes in ocean uptake. In addition to the changing ocean sink, drought and heat wave conditions may change the uptake of carbon on land. The infamously hot summer of 2003 in Europe for example cut the rate of photosynthesis by 50%, dumping as much carbon into the air as had been taken up by that same area for the four previous years [Ciais et al., 2005].
The warming at the end of the last ice age was prompted by changes in Earth’s orbit around the sun, but it was greatly amplified by the rising CO2 concentration in the atmosphere. The orbits pushed on ice sheets, which pushed on climate. The climate changes triggered a strong positive carbon cycle feedback which is, yes, still poorly understood.
Now industrial activity is pushing on atmospheric CO2 directly. The question is when and how strongly the carbon cycle will push back.
—–
Canadell, J.G., C.L. Quere, M.R. Raupach, C.B. Field, E.T. Buitehuis, P. Ciais, T.J. Conway, N.P. Gillett, R.A. Houghton, and G. Marland, Contributions to accelerating atmospheric CO2 growth from economic activity, carbon intensity, and efficiency of natural sinks, Proc. Natl. Acad. Sci. USA, doi 10.1073, 2007.
Ciais, P., M. Reichstein, N. Viovy, A. Granier, J. Ogee, V. Allard, M. Aubinet, N. Buchmann, C. Bernhofer, A. Carrara, F. Chevallier, N. De Noblet, A.D. Friend, P. Friedlingstein, T. Grunwald, B. Heinesch, P. Keronen, A. Knohl, G. Krinner, D. Loustau, G. Manca, G. Matteucci, F. Miglietta, J.M. Ourcival, D. Papale, K. Pilegaard, S. Rambal, G. Seufert, J.F. Soussana, M.J. Sanz, E.D. Schulze, T. Vesala, and R. Valentini, Europe-wide reduction in primary productivity caused by the heat and drought in 2003, Nature, 437 (7058), 529-533, 2005.
Le Quere, C., C. Rodenbeck, E.T. Buitenhuis, T.J. Conway, R. Langenfelds, A. Gomez, C. Labuschagne, M. Ramonet, T. Nakazawa, N. Metzl, N. Gillett, and M. Heimann, Saturation of the Southern Ocean CO2 sink due to recent climate change, Science, 316 (5832), 1735-1738, 2007.
Schuster, U., and A.J. Watson, A variable and decreasing sink for atmospheric CO2 in the North Atlantic, J. Geophysical Res., in press, 2007.
Ray Ladbury says
James, while I think the “linear-no-threshold” model is flawed, there is no convincing evidence that directly contradicts it, and so the NAS panel is probably correct in adopting it. It would be a grave mistake to underestimate the difficulties of long-term storage of radioactive waste or the health consequences if the storage should fail. The strategy adopted by the US of “put it in the ground and forget it” is a nonstarter. First, without reprocessing, not only are we burying a lot of fuel, but the volume of waste is unmanageable. Second, most of the longest-lived nastiness is can be recycled, leaving a highly radioactive, but shorter-lived problem. Of course this raises proliferation concerns, and these also should not be underestimated.
Likewise, renewables also pose daunting problems. I think that most advocates have not thought through the level of effort needed to meet projected energy demand. Given the toxic residue that is often produced by semiconductor fabs, the challenges of managing the waste on a scale needed to meet demand with solar energy are not insignificant. And storage is an issue for any renewable, and the challenges of scale here have not been dealt with. Transport remains a technology where renewables haven’t made a dent and don’t look promising for the future.
So far the only useful thing the skeptics have brought to the table is their emphasis on these difficulties–difficulties often glossed over by advocates of both renewables and nuclear power. If they would abandon their silly opposition to established science and accept that we face serious risks, they could perhaps make some valuable contributions to the debate about how to handle climate change. They need to understand the difference between conservatism and complacency.
James says
Re #651: [The strategy adopted by the US of “put it in the ground and forget it” is a nonstarter. First, without reprocessing, not only are we burying a lot of fuel, but the volume of waste is unmanageable.]
I agree that it is a far less than optimal strategy, but it would work, especially if we consider the example of Oklo. A billion years or so should be containment time enough. Nor should the volume be unmanagable: the uranium and other materials originally came out of mines, so why shouldn’t it fit back in?
[Of course this raises proliferation concerns, and these also should not be underestimated.]
Yes and no. I agree that those should be serious concerns, but as nothing is ever done (except by the Israelis) about the proliferation that is happening anyway, then we should at least get the benefit of CO2-free power. But the subject gets further into politics than I think we should go here.
J.S. McIntyre says
re 652
“A billion years or so should be containment time enough.”
Of course it would. The Sun would have boiled away our atmosphere by then, or be near to finishing the job.
Hank Roberts says
Following one of the cites to the article I posted for James earlier brings this digression a bit more back on track.
The concept of a “sink” biologically applies to wildlife in the Chernobyl exclusion zone — as it does to animals and plants that bind carbon dioxide.
Understanding what a “sink” means may be helpful. This is a look at how it’s investigated in the Chernobyl exclusion zone — which is a “sink” for wildlife.
Useful methods for studying and understanding how biologists identify “sinks” — places that on average more life flows into and dies without reproducing successfully.
http://www.esajournals.org/perlserv/?request=get-abstract&doi=10.1890%2F1051-0761(2006)016%5B1696%3ACAAPSF%5D2.0.CO%3B2&ct=1
“Previous studies have revealed severe reductions in Barn Swallow reproductive performance and adult survival in the Chernobyl region, implying that the population is a sink and unable to sustain itself. Female Barn Swallows are known to disperse farther from their natal site than males, implying that female stable-isotope profiles should tend to be more variable than profiles of males. However, if the Barn Swallows breeding at Chernobyl are not self-sustaining, we would expect males there also to originate from a larger area than males from the control region. We found evidence that the sample of adult Barn Swallows from the Chernobyl region was more isotopically heterogeneous than the control sample, as evidenced from a significant correlation between feather δ13C and δ15N values in the control region, but not in the Chernobyl region. Furthermore, we found a significant difference in feather δ15N values between regions and periods (before and after 1986). When we compared the variances in δ13C values of feathers, we found that variances in both sexes from post-1986 samples from Chernobyl were significantly larger than variances for feather samples from the control region, and than variances for historical samples from both regions. These findings suggest that stable-isotope measurements can provide information about population processes following environmental perturbations.”
Dan Hughes says
re: #616
List all the potential methods/systems for terawatt and greater base-load electricity generation that can provide the exact same performance and reliability all day every day for 10s of decades.
I think it’s a short list of two item; fossil and nuclear.
Nick Gotts says
Re #652 (James) “as nothing is ever done (except by the Israelis) about the proliferation that is happening anyway, then we should at least get the benefit of CO2-free power.”
An odd claim, in the light of recent events surrounding North Korea (apparently dismantling its bomb-making programme in response to some combination of bribes and threats), Libya (where Qaddafi has in the same way been persuaded to abandon his programme), Pakistan (which has at least promised to stop spreading nuclear weapons technology, and blamed it all on A.Q. Khan) and Iran (which as I recall is currently under some sort of pressure to stop enriching uranium). If you look at predictions from a few decades ago, I think you’ll find the general expectation was for far more than the current 8 or 9 nuclear-armed states by now. Of course, increasing reliance on nuclear power would make it far harder to prevent further proliferation, given the inextricable connections between the materials, technologies and skills involved.
J.S. McIntyre says
re 655
List all the potential methods/systems for terawatt and greater base-load electricity generation that can provide the exact same performance and reliability all day every day for 10s of decades.
I think it’s a short list of two item; fossil and nuclear.
=================
And both present huge problems, in the case of Nuclear incredibly lethal, long-lasting problems.
My point is you have to factor these issues in, otherwise your “precautionary principle” is a faux argument.
Further, you need to factor in the understanding it isn’t only about REPLACING power, watt for watt, but factoring in efficiencies and reductions. Don’t get me wrong; I would like nothing more than for nuclear to work, but the problems associated with it are so prevelant, so long-lasting with the very real potential for harmful consequences that pushing an “if not fossil, nuclear” argument is a non-starter, particularly if your intent is to convince me or anyone else who have valid concerns otherwise.
Bottom line: trying to suggest this is an either/or argument is a fallacy.
SecularAnimist says
Dan Hughes wrote: “List all the potential methods/systems for terawatt and greater base-load electricity generation that can provide the exact same performance and reliability all day every day for 10s of decades.”
Full exploitation of the capacity for small-scale distributed rooftop photovoltaics can eliminate much of the need for “terawatt and greater base-load electricity generation” in the developed world, and can provide electricity for hundreds of millions of people in rural areas of the developing world where large-scale power plants and large-scale electrical distribution grids are economic impossibilities.
While large-scale centralized wind turbine “farms” and concentrating solar power plants are playing and will play an increasingly important role, the future of electricity generation is in small-scale distributed generation. As the personal computer revolutionized “data processing” and the cell phone revolutionized telecommunications, cheap distributed photovoltaics and small-scale wind turbines will revolutionize the production, distribution and use of electricity. Large centralized electrical generation plants of any kind will be increasingly less important as time goes on and it is arguable that coal, natural gas and nuclear power plants are already bad investments since they will be obsolete well within their expected operational lifetimes.
James says
Re #656: [An odd claim, in the light of recent events surrounding North Korea…]
North Korea couldn’t dismantle its nuclear program if it hadn’t had one (and according to reports some of the “dismantling” involved shipping things off to Syria), and bribing one to stop would seem to encourage others to start. Iran may be under pressure, but what’s that pressure doing? Nothing, as far as I can see. As for Pakistan… well, what’s a promise worth, in international politics?
This is veering off into politics, and into some iffy things that depend on intelligence assessments and suchlike.
To return to the main thread, it seems as though on the one hand we are offered all the possible negatives (some of them IMHO extremely stretched, and none of them exactly certain) of nuclear power, while on the other hand the known destructive power of fossil fuels is – even here – largely ignored, and the possibilities of “renewables” greatly exaggerated, and most of the technical problems glossed over. That’s hardly a realistic approach, and we do very badly need to deal with reality.
David B. Benson says
James (659) — Find out how well Brazil is doing with renewables, mostly ethanol from sugarcane. No exaggeration.
Rod B says
Brazil is doing quite well with ethanol renewables, but, given its overall requirement and, especially, its unique ability to grow massive sugarcane, it is not a practical model that can be replicated all over.
David B. Benson says
Rod B (661) — That’s why the North should buy ethanol and other biofuels from the South rather than subsidize biofuel production in the North. (And incidently, India is another big producer of sugarcane as well as other southern locations.)
I’m not talking about all forms of bioenergy. Generating electricity from biomass energy is quite sensible.
Chuck Booth says
Re # 633 Matt: “If biodiversity “only” costs $30B relative to a world economic output of $50T or so, then it seems reasonable to try and solve.”
Rather than focus on the estimated cost of preserving current biodiversity, it might be more useful to consider the cost of losing the ecosystem services provided by that biodiversity should it be diminished – these services include:
1. Provisioning, including food, water, fuel, and fiber.
2. Regulating, such as the prevention of soil erosion and flooding.
3. Cultural, including recreation, spiritual values, and a “sense of place.”
4. Basic support, including soil formation, nutrient cycling, and oxygen from photosynthesis.
And in considering how AGW might impact these services, you have to consider other, simultaneous, threats to those services, such as deforestation, pollution, eutrophication, over-fishing, spread of invasive species, etc.. AGW shouldn’t be considered in isolation.
And while the loss of one species of beetle (or a dozen species) might seem inconsequential, you can never be sure; it is like removing bolts one by one from a jet airliner (or the space shuttle, or the furnace in your house)- you never know which missing bolt is going to cause catastrophic failure of the entire system.
Here are some useful references on ecosystem services provided by the plants and animals with which we share the earth:
Stokstad,E. 2005. Taking the Pulse of Earth’s Life-Support Systems. Science
Vol. 308. no. 5718, pp. 41 – 43
http://preview.tinyurl.com/2s543r
Schröter, D. et al 2005 Ecosystem Service Supply and Vulnerability to Global Change in Europe. Science Vol. 310. no. 5752, pp. 1333 – 1337
http://preview.tinyurl.com/2v8up5
Worm, B. et al. 2006 Impacts of Biodiversity Loss on Ocean Ecosystem Services. Science Vol. 314. no. 5800, pp. 787 – 790.
http://preview.tinyurl.com/2r2b2p
Jim Galasyn says
Re ecosystem services and biodiversity in 663:
Thanks to Chuck for the post and the excellent links.
James says
Re 662: [Generating electricity from biomass energy is quite sensible.]
To some small extent, yes, but to generate large amounts of energy from biomass requires the conversion of large amounts of land to croplands, which brings us back to the biodiversity issues again.
One thing most of the renewable energy sources have in common is that their advocates seem to lack a sense of scale. Biomass, like wind generators, photovoltaics, and the rest all look good when applied to your off-the-grid house located on your couple of hundred acres of land. The problem is that there’s just not enough Earth for everyone to live that way.
AK says
Another energy storage technology that apparently is already in production is Vanadium Redox Battery Energy Storage System. It is being marketed by a company called VRB Power Systems.
According to the company’s spec sheet the Annual Operations & Maintenance Costs are $0.008/kWh, which adds up to ~$10,000/year for 20 hours of Nevada Solar One.
The power and storage capacity are independently scalable:
A system designed to store the output of Nevada Solar One for 20 hours might cost, today, somewhere around $250 million, based on a large unit cost of $200/KWh. This compares well with the cost of Nevada Solar One, itself: $220-250 million.
Of course, all this information is based on the company’s own Web site, but I suppose anybody wanting confirmation could contact some of their customers.
These prices aren’t competitive today, but that’s probably mainly due to the small scale, as well as subsidies and price supports for traditional power.
Lawrence Coleman says
I think I can grasp the complexity of the CO2 sink/source issue. I expect it also depends on the roughness of the seas stirred up by hurricanes or areas of low pressure especially at mid latitudes. Allowing more cold CO2 rich water to the surface, then if a meterological low is sitting above that area it would tend to act as a local CO2 source dumping CO2 into the atmosphere. I would guess near the equater the seas are calm and warm and relatively high pressure systems above the ocean so it should act as a CO2 sink despite the fact that less CO2 can be dissolved into warm water. The polar regions are the breeding grounds for crustations such as krill and plankton thus the cold deep water would have a high concentration of CO2 and since that latidude is also very stormy with billions of gallons of deep water brought up to the surface releasing it’s load of CO2 it would temd to be a CO2 source as well. Am I on the right track?
James says
Re #666: [A system designed to store the output of Nevada Solar One for 20 hours might cost, today, somewhere around $250 million…]
Interesting, but there’s another cost which you don’t mention, which is storage losses. Nothing is 100% efficient, and from the FAQ at their web site this doesn’t seem to be even close.
“The system provides a roundtrip efficiency of 65 – 75%. Therefore with the input of 25 -35% additional power to cover the losses…”
So to use this with a solar or wind plant, you take an already not very high density power source, and chop 25-35% off of that while doubling the plant cost. Doesn’t seem like a sound economic decision to me. I’d think it much better to have baseload generation which, like hydro or nuclear, can generate power as needed, without storage losses. Then you can run a good fraction of wind & solar on top of that.
AK says
Re #668
Perhaps. IMO all the technologies should at least be on the table. Current designs for CSP have the mirrors spread out widely, presumably because they are much more expensive than the land. But this could change, as could the cost of systems like VRB. I especially like the disconnect between storage and power. To store more MWh, just build bigger tanks.
I like flywheels for the long run, they’re already in use in power balancing. Of course some redesign would be necessary to eliminate costly features not needed for long-term storage with smaller loads. I found round-trip efficiencies of 90% mentioned during earlier searches, (couldn’t find one in a quick search today,) which could put it much closer to transmission losses. But they’re not ready OTS today.
And in the longer run, I still like SBSP, although it certainly won’t be cost effective until we can access Lunar material.
Hydropower (including power storage) tends to be hard on the environment, including human residents. As for nuclear, I don’t have a problem with it, but IMO it shouldn’t be assumed that political situations will necessarily allow it to be used.
ianric says
Why would anyone believe that the oceans are close to CO2 saturation? 3.6E19 g CO2 dissolved in 1.4E21 kg seawater gives an average concentration of 0.026 g/kg. At 0 degrees centigrade water can solvate 3.35 g/kg and at 20 degrees centigrade the number is 1.69 g/kg. Pretty far from saturation I would say. Solvation is of course influenced by salinity and acidity as well, but in this case Henry’s law applies. The solution is dilute and only a tiny fraction of the CO2 reacts with water to form carbonic acid.
Ray Ladbury says
ianric, re 670. well except that the water in question is just the surface water, and mixing with the deep ocean is slow. Moreover, the falling Ocean pH would suggest that you are wrong.
ianric says
Re 671
I realize I used the wrong figures in my first comment. These should be more like it.
Deep ocean: 1.4E20 g CO2 / 1.3E21 kg H2O = 0.11 g/kg.
Surface ocean: 3.7E18 g CO2 / 7.2E19 kg H2O = 0.052 g/kg. Interesting to note is that the deep ocean has a koncentration of CO2 double that of surface water.
Still far from saturation. And with pH well over 8, the ocean should function as carbon sink for a long time yet. On the other hand, with calm waters, the top layer of a few metres could of course become temporarily saturated. Just like a field of growing crop can suck the air void of CO2 on a day without wind.
Ray Ladbury says
ianric, keep in mind that the Ocean doesn’t have to STOP absorbing CO2, even a slowdown has dramatic implications. CO2 emissions keep increasing, temperature is warming and CO2 concentration in the oceans is increasing. It is not enough to look at the equilibrium–you also have to look at the rate.
neil cox says
I’ve given medium amounts of thought on most of these topics. I suppose the USA could come up with 8 billion as it’s share of 80 billion world wide, but I have seen little detail on how the money would, or should be spent. I suspect half of the species loss is in Brazil. Purchasing land there as bio preserves is reasonable, but will surely be regarded as meddling in Brazil’s internal affairs if we buy up several billion dollars worth of Brazil’s land. Also how can we be reasonably assured that good jugement will be used in selecting the pieces of land to purchase? How can we be assured that the land will remain an effective biodiversity preserve long term? Are details available? I’m suspicious that this is another scam to make a few people rich.
I’ve been collecting details on SSP = space solar power for about 2 decades. It clearly is not competitive with coal before 2030 unless we assign huge amounts of collateral damage to coal. Since coal likely puts more radiation in Earth’s atmosphere than nuclear power by the KWH, and has other collateral damage it causes, huge may be prudent. If we spend 80 billion on SSP, before 2030, we have no guarantee that SSP will look good after 2030, but that is true of all our other options, so I am urging a demonstration SSP by 2012, sooner, if we can get reasonably organized. http://spacesolarpower.wordpress.com
The 80? billion invested in wind power so far seems to have a good shot at being money well spent, so I recommend another 80 billion for wind power before 2012.
We need to make an 80 billion dollar commitment to photovoltaic in the next year or two or the manufacturing capacity for photovoltaic won’t be available in 2013 for the next scale up of SSP.
While present heavy lift is ok for a demonstration SSP, we won’t have a practical way to get the 2013 larger SSP even to LEO = Low Earth Orbit, unless we invest another $80 billion plus in heavy lift. Perhaps this amount has already been appropriated.
Three of my other favorites are http://www.liftport.com http://www.skywindpower.com and very large high altitude balloons, which each need a few million dollars near term to make progress. Neil
Ray Ladbury says
Neil,
space-based solar power is a fantasy. None of the analyses I’ve seen have had a reasonable treatment of the costs–particularly launch costs–or of the threats to a space-based system–e.g. radiation degradation, etc. Yes, the sun is brighter in space, but does that help you all that much after your cover glass darkens after a few years. Right now, it costs $10 Grand to launch a soda can into space, and I don’t see that changing any time soon. Some problems are not unsolved because nobody has tried; some are unsolved because they are damned hard to solve.
AK says
Re: 675
Ray, it may be true that such costs haven’t been included in the more forward-looking analyses, but part of the reason for that is we don’t know how far they can be brought down because we haven’t done the R&D yet. Unless the money gets allocated for the research now, we won’t know ten years from now.
Radiation damage? Who knows what workarounds or solutions could be found if people were looking hard for them. Are we speaking of Galactic Cosmic Rays here, or short-wave stuff and particles that could be stopped by a piece of aluminum foil? Gallium Arsenide PV cells can (AFAIK) accept power densities orders of magnitudes higher than solar at Earth orbit, so perhaps concentrating mirrors can focus sunlight into radiation-protected chambers, where the PV cells can do their job protected from radiation. For that matter:
Do they really need glass covers? Could an automated robotic replacement schedule be set up to deal with this need? Etc., etc.
While extended discussion of technical issues probably isn’t on-topic here, I’m sure your contributions would be very welcome at http://spacesolarpower.wordpress.com in identifying problems for would-be solvers and helping select targets for research.
Ray Ladbury says
A. K., Yes, while it is somewhat off-topic, I think that it is germane because it is indicative of a trend I see–technological optimism requires ignorance to survive. Having worked on satellites for over a decade and with manned space flight for a few years, I can tell you what I’ve learned: Doing things is space is hard. Robotic replacement? Great idea–ever hear of the DART mission? And yes, GaAs is rad hard, but it is expensive compared to other technologies and it still degrades over a period of years. Finally, everything comes back to the fact that you are fighting a very deep gravitational well. I have to say that I am very pessimistic about ever realizing a scheme like this. The unfortunate thing about technical systems is that they break, and fixing them is much easier on the ground.
But as I said, this illustrates a general problem I see–people tend to gloss over difficulties for their favorite techno-fix. Pro-nuke guys assert that waste storage can be solved and proliferation concerns can be managed–even though no scheme has convincingly addressed these concerns heretofore. Renewables advocates ignore the very real problems of storage, peak demand, and even the sheer scale of the energy problem we are facing going into the next century.
Economies of scale are wonderful, but they are not universal. It still takes 1 teacher for every 15 students for effective education. It still takes one-on-one interaction for effective medical treatment. And all the technology in the world has not changed that. We still don’t have flying cars or moon bases. I am all for investment, but not every technology has equal probability of success.
The same goes for remediation of climate change in general. Economist/business types want to attack the science or carry out some geoengineering solution, while the people who actually understand the science say our economic system will have to change. Each seems to look to the area of their ignorance to preserve hope.
AK says
Re: 677
Well, either we can ignore the problem and hope it goes away, or we can address it. Technology has solved a lot of problems, but so far, AFAIK, nobody has succeeded in changing human nature, and the experiments in that regard have been pretty horrendous.
My own experience in software development tells me that problems look a lot bigger before you get a good team to work trying to solve them. If you use “tried and true” methods (as sold by the big consulting firms), a big project gets bigger as it goes along, and ends up with around 25% chance of success. The same problem approached by creative people with proper management and front-end analysis can get the problem solved much more cheaply without cost overruns. The difference is a management problem, not technical.
So, when I’m told that NASA has had a hard time solving the problems with robotics in space, what I hear is that NASA can’t solve them, not that they can’t be solved. But, even in solving management problems, you can’t ignore human nature. The difference between bureaucracy and weeds is that bureaucracy can appear through spontaneous generation. Once present, they’re both very hard to get rid of.
IMO, dealing with climate problems will require small, agile, bureaucracy-free organizations, with the needed enthusiasm and esprit, properly defined targets, and good budgets. They must have the money to pay for what they need without anybody being able to divert it into personal foibles.
How to accomplish that, within the bounds of human nature, I don’t know. But what I can do is point out the possible technologies and the problems needing to be solved. For instance, the storage problem has several solutions on the table, with different parameters and levels of maturity. CSP has enough of a track record that we can (roughly) predict its development cycle and cost evolution. PV cell technology is similar enough to chip tech that we can roughly predict a steady cost decrease, with proper attention to research. Mass production and economies of scale can be expected to bring down the cost of wind power, etc.
Where space comes in is that there’s no other power source (except perhaps nuclear fission) that can be deployed to provide 10-20 terrawatts of energy without having major impacts on the environment. If space is too expensive, we need to allocate enough money to R&D to bring the costs down. If launching is too expensive (in $ or environmental cost) we need to allocate money to R&D to provide other solutions. If space robotics isn’t developing fast enough, we need to take the money away from the bureaucrats and give it to people who know how to solve problems without writing a rule book first.
You mentioned the DART Mission. This, IMO, is a perfect example of why NASA isn’t creating what’s needed for orbital operations. We have the communication technology so a human on the ground could perform remote control (with perhaps a fraction of a second lag). The robotics technology was clearly in place. But they evidently just threw it over the wall, hoping the robot could perform by itself. This may have been useful for automated operations in Mars orbit, but what’s needed for NEO or GEO is a robotic system for the high-speed reactions running under close remote control from the ground. If we can beam bandwidth between points on earth via satellite, we should be able to get the same 2-way bandwidth between a ground control station and a robotic satellite/vehicle.
Another point, this experiment failed in mid-2005. Why was there no follow-up? Where is the stream of repeated efforts, each learning from the previous failures? Why was there so little instrumentation? Did the people planning this mission expect it to be a complete success the first time? Why?
IMO, this isn’t the way to achieve rapid technological progress, it’s the way bureaucrats manage a space program nobody seems to care about. Assumptions that space research won’t happen because NASA can’t do it are completely invalid. What’s needed is to take the entire space program away from NASA and give it to some organization(s) not full of bureaucrats.
A carbon tax is a good way to encourage energy conservation, and tilt the balance towards carbon-neutral energy, and a good deal of the money generated should be allocated to space research, but not one penny should go to NASA.
Hank Roberts says
Who knows more about the oceans than the US Navy?
Perhaps it’s time for another round of declassification?
This is interesting:
http://stinet.dtic.mil/cgi-bin/GetTRDoc?AD=ADA473826&Location=U2&doc=GetTRDoc.pdf
Title: The Age of Consequences: The Foreign Policy and National Security Implications of Global Climate Change
Fields and Groups :
040200 – METEOROLOGY
050400 – GOVERNMENT AND POLITICAL SCIENCE
Corporate Author:
CENTER FOR STRATEGIC AND INTERNATIONAL STUDIES WASHINGTON DC
Hank Roberts says
p.s., apologies for the somewhat tangential post, but this is worth reading. Quoting a bit from the article I linked to above. This is a serious group of policy planners thinking what many climate scientists still seem to think is unthinkable, scenarios including catastrophic tipping into a new climate very fast:
—– excerpt ——
The mandate of the exercise was, on its face, very
straightforward: employ the best available evidence
and climate models, and imagine three
future worlds that fall within the range of scientific
plausibility. … The scenarios in this report
use the timeframe of a national security planner:
30 years, the time it takes to take major military
platforms from the drawing board to the battlefield.
The exception is the catastrophic scenario,
which extends out beyond fifty years to a
century from now.
The three scenarios are based on expected, severe,
and catastrophic climate cases. The first scenario
projects the effects in the next 30 years with
the expected level of climate change. The severe
scenario, which posits that the climate responds
much more strongly to continued carbon loading
over the next few decades than predicted by
current scientific models, foresees profound and
potentially destabilizing global effects over the
course of the next generation or more. Finally, the
catastrophic scenario is characterized by a devastating
“tipping point” in the climate system, perhaps
50 or 100 years hence. In this future world, global
climate conditions have changed radically, including
the rapid loss of the land-based polar ice sheets,
an associated dramatic rise in global sea levels, and
the destruction of the existing natural order.
… Each climate scenario was carefully constructed and the three corresponding national security futures were thoroughly debated and discussed by the group.
Although the intersection of climate change and
national security has yet to be fully mapped,
scholars and strategists certainly have explored this
territory in recent years. We felt it was important
to begin this study by looking at this literature,
in order to understand how we both build on and
depart from the existing intellectual framework.
——end excerpt——