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John Bruno at 08:35 AM on 13 July 2010Must-read article on ocean impacts by ocean scientists
PatriciaW: I am curious why you say "It is unfortunate that the authors of this article still repeat the long since abandoned target of under 450ppm" Because it is too high, too low, unrealistic or because you don't agree with the idea of setting a limit of ppm goal? Also, that is a pretty sweeping statement you make... Also, I don't know of science predicting acidification will kill off phytoplankton. Some that secrete calcarious shells will suffer, but overall it is unclear how climate change will affect primary production (and I don't think falling atmospheric O2 levels are a problem). On the one hand, reducing mixing and upwelling appear to be reducing production in some places. On the other hand, warming and increased CO2 conc. should/will stimulate photosynthesis and primary production. Although, it gets even more complicated than that, as warming also stimulates animal metabolism, to an even greater degree, thus, we think we will be seeing more grazing of phytoplankton and reduced phytoplankton standing stock, but this would obviously increase net ocean photosynthesis. Ill do a complete post on this soon... andthorne: you are wrong. this is baloney. apeescape: an increase in chlorophyl in the oceans should actually be interpreted as an increase in primary production (although it is a bit less straightforward than that). I am unfamiliar with those papers... - John B PS: Sorry the Science papers are not publicly available. -
Riccardo at 08:19 AM on 13 July 2010Sea level rise is exaggerated
Surprisingly consistent, indeed. Good job Peter. -
andthorne at 08:00 AM on 13 July 2010Must-read article on ocean impacts by ocean scientists
The cause of rising temperatures and acid levels in the ocean can be attributed to the explosions in the deep sea bed of methane hydrates. They are recognized as the cause of mud volcanoes; the methane leaks through them, oxidizng ultimately to CO 2, using a lot of oxygen in the process. A long the oxidizing way it converts to formalin and water. Formalin is not very good for sea life and water raises sea levels an evaporation rates to our atmosphere. In the air it converts to formaldehyde and water vapor, again contributing to Global Warming. M -
kdkd at 07:52 AM on 13 July 2010Hotties vs Frosties?
I'm also impressed with the rhetorical approach that BP takes in post 109 given his repeated assertion that the only thing that is important is the evidence. It's becoming increasingly clear that as with Ken Lambert the only things important to BP are his preconceived notions of what the "correct" conclusions will be in advance. However this is usually hidden behind some technical sounding stuff illustrating small picture thinking which obscures the poor quality reasoning enough to give a veneer of respectability. -
kdkd at 07:45 AM on 13 July 2010Hotties vs Frosties?
KL#102 After BP#140: "each piece of evidence should be able to stand on its own right, irrespective of any support that may or may not come from another domain" (#40). In an ideal world this statement would be true but for complex stochastic systems with high levels of measurement uncertainty this statement is merely advocacy for impasse and the weight of the evidence be damned. -
Peter Hogarth at 07:12 AM on 13 July 2010Sea level rise is exaggerated
daniel at 12:31 PM on 12 July, 2010 I have also looked at what we can say about short term trends from the paleo data. If your hypothesis was “likely” we should see random or high variations in trend away from the overall trend when looking at any approximate 150 year period in the overall time period. These variations are not random and not large.
These are trends from every four consecutive paleo points. I have also taken gradients from three consecutive points, as a three or four point record from this data encompasses a period most similar to the tide gauge data (roughly 150 years). I have also added the shorter New London tidal series (running annual average) for comparison. We should be cautious with this crude approach, but it’s not a “trick”, we treat all paleo data consistently. We allocate a “centre” date for these mini-series, then finally add the measured trends from the two tide gauge series with a centre date for these (solid points below). I am aware I have argued against this breaking up of time series elsewhere, but on this occasion we are actually looking for any evidence of short term changes in gradient - whilst still honouring all of the points in the overall analysis by generating a series of overlapping trends. If deviation of the points from mean trend was high, we would expect inconsistent or noisy results. If large variations had occurred, we would expect to see some significant changes in gradient, especially on such short series. If there was no acceleration in trend, we would see a flat line, or an insignificant trend.
The results are surprisingly consistent, all linear fit trends are significantly positive. The derived rate of increase in trend (just from the paleo data) is clear and consistently positive. The addition of the tidal data confirms and increases this trend, showing late period acceleration and giving strong evidence that the most likely earlier and later trends are close to those suggested by Donnelly, whilst also suggesting short and medium term variability similar to the tide gauge data, (which is intuitive). The second order fits are not meant to represent possible variation, but simply to indicate the significant positive second order component, ie acceleration. This analysis supports the conclusions of the paper, and does not support your suggestion.
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scaddenp at 07:04 AM on 13 July 2010Hotties vs Frosties?
MP - I think you are being impressed by a denial tactic that "we saving the world from an ice age by adding CO2". This supposed touching concern for humanity thousands of years into the future is I suspect more motivated by concern about price of gas tomorrow but no matter. If this concern was genuine then it would make more sense to save every bit of carbon now for use in the future when needed. As to old saw about running out of rocks - maybe it would be better to say we will move to better sources of energy when we start paying the true cost for petroleum. Even removal of $500 billion of subsidies would be good start dont you think? BP - I find David MacKay's "Sustainable Energy without the hot air" a valuable analysis as to the potential for renewables. While he analysis would also suggest that nuclear has to be part of some countries needs, (Europe) he also makes a mockery of the statement of "Anyway, you can do the math, renewable energy is absolutely insufficient to maintain the necessary energy supply to world economy, even in the short run." -
Peter Hogarth at 06:53 AM on 13 July 2010Tai Chi Temperature Reconstructions
johnd at 06:09 AM on 13 July, 2010 John, thanks, but you misquote me. I did not dismiss CO2, nor would I. I was referring to the high correlation with temperature and lower correlation with CO2 found by many workers, and I justified this. The author of your first reference (I read this last year) should know as this is Buntgen !!!! Esper is also a co-author! The second reference doesn't link, but don't think I've read this one. I'll see what I can dig up on CO2 and growth. -
johnd at 06:09 AM on 13 July 2010Tai Chi Temperature Reconstructions
Peter Hogarth at 07:20 AM, following up on your dismissal of CO2 being a factor in increased growth, these two studies are interesting and relevant. Larch Budmoth Outbreaks in the European Alps shows how rising CO2 may be related to increased growth due to the lack of periodic growth depressions that characterise larch growth. Changes in needle quality and larch bud moth performance in response to CO2 enrichment and defoliation of treeline larches studies the effects in CO2 enrichment trials. -
KR at 05:08 AM on 13 July 2010Hotties vs Frosties?
And here's a better summary of the Sci. Am. article on renewables. The world will need an estimated 16.9 terawatts of power by 2030, up from 12.5 TW today. Available wind power is estimated at 40-85 TW, available solar power at ~580 TW. Cost per KW could be lower than building new coal power plants, even with the required long distance power lines. Bird deaths (an issue raised with wind farms) are estimated at ~1/10 that from coal plants (pollution), so that's not an obstacle. And wind/solar power generation is hugely less wasteful of water resources (no cooling towers or hot rivers) than coal, oil, or nuclear power, relaxing fresh water needs. Siting multiple wind/solar sources separated by a reasonable distance (~5 up and down the East Coast of the US, for example, or even a few hundred km between stations) overcomes regional wind/solar variations, allowing a fairly level supply regardless of weather. And if we move our transportation to an electric basis (that's difficult - batteries still *suck* for energy density), we could even drop our power requirements below current levels. It's not all simple, mind you - there are rare-earth resource limitations for motors/solar cells, mostly from China, and a considerable investment. But it can be done. -
Philippe Chantreau at 04:35 AM on 13 July 2010Hotties vs Frosties?
"Inefficient wind turbines" Well, let's consider the efficiency of a wind turbine based on the ratio of the energy it actually produces for a given wind speed vs. its Beck limit. On the table below, we find, at 10 mph wind, a Beck limit of 37.70kWh/mo and a realistic turbine output of 22.36, whcih gives an efficiency close to 59%. http://www.ndsu.nodak.edu/ndsu/klemen/Perfect_Turbine.htm In comparison, a coal power plant can be expected to reach about 31%. http://wiki.answers.com/Q/What_is_the_energy_efficiency_of_an_average_coal_powered_plant If I remember, combined cycle could possibly reach 40 or 45%. Not quite as good but still more efficient than BP's rethoric. BTW, BP, thanks for the pic, with all the oil covered pelicans in the news these days, it's nice to see something aesthetically pleasing. Just to clarify: I have stated on this forum many times before that I am in favor of using nuclear energy. -
apeescape at 03:54 AM on 13 July 2010Must-read article on ocean impacts by ocean scientists
(linked from original paper) SeaWiFS data show increase in chlorophyl in the oceans which links to loss of primary production. Polovina, J.J., Howell, E.A., Abecassis, M. (2008). Ocean's least productive waters are expanding. Geophysical Research Letters, 35(3) DOI: 10.1029/2007GL031745
Though more data is needed.
Henson, S. A.; Sarmiento, J. L.; Dunne, J. P.; Bopp, L.; Lima, I.; Doney, S. C.; John, J.; Beaulieu, C. Detection of anthropogenic climate change in satellite records of ocean chlorophyll and productivity. Biogeosciences 7 (2010): 621-640, doi:10.5194/bg-7-621-2010.
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KR at 03:29 AM on 13 July 2010Hotties vs Frosties?
Here's a better link to the Scientific American sustainable energy proposal. -
KR at 03:26 AM on 13 July 2010Hotties vs Frosties?
Berényi - I would completely agree that nuclear power will need to be part of the energy mix moving forward, at a much larger percentage than it is now. However, there was a very interesting article in the Nov. 2009 issue of Scientific American detailing how wind, solar, and wave energy could supply 100% of energy requirements in the next 20-40 years. Not ethanol, mind you - that would require several times the area of the Earth to match up, not to mention several times the available world-wide fresh water. You might want to look up a copy if you can get your hands on it. I believe there's a lot more potential in renewable energy than you seem to. -
chris at 03:19 AM on 13 July 2010Hotties vs Frosties?
MP at 18:37 PM on 12 July, 2010 MP your argument is scuppered by a fundamental flaw unfortunately. The only one of your set of possible scenarios is your scenario #1. The reason is that there simply will not be "a new glacial period" within the next 10 millenia (analysis of the Earth's highly predictable orbital properties that govern the transitions between glacial periods indicate that the present interglacial might actually last another 50,000 years). Clearly we need to address the immediate problems (increasing global warming, sea level rise, major disruption of current hydrological cycles etc.) that impact during the coming decades, and the related longer term problem (an absolute imperative to realign the powering of our societies with sustainable energy sources at least within the next few hundred years), before worrying about what might happen many thousands of years from now! -
Alexandre at 03:12 AM on 13 July 2010Must-read article on ocean impacts by ocean scientists
apeescape #3 Thanks, I was going to ask for that. -
Peter Hogarth at 03:10 AM on 13 July 2010Sea level rise is exaggerated
daniel at 12:31 PM on 12 July, 2010 On data point 1, you state “It is also.... statistically speaking...... on the 1.2mm/yr trend” if we are talking just the non-tide gauge data, I agree, but we are not. “Therefore so is the tide gauge data”. This is incorrect. I have included error bars on the tide gauge data. Do the error bars on the paleo data overlap the tide gauge trend? Yes. Do they overlap the paleo trend? Yes. Could this point be on both trends, Yes. Do the error bars on the tide gauge data overlap the extended paleo trend? No. Could they be on this paleo trend? No. Clearly the trends diverge (and continue to do so). We must accept that the tide gauge record from close to the site in question shows a 150 year relative sea level trend which is in excess of 2 mm/yr. It is important to see that this trend is smooth at decadal timescales over the entire 150 year period. There is no inconvenience to me here, perhaps a basic misunderstanding on your part?
The light grey line is the paleo trend. Red is NY tide gauge MWL. Blue is New London tide gauge MWL. New London is relatively local to site. Next I will look at the paleo trends in more detail.
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Berényi Péter at 02:56 AM on 13 July 2010Hotties vs Frosties?
#98 MP at 18:37 PM on 12 July, 2010 just as the Stone Age ended, not because the earth ran out of stone or a stone tax was introduced, the carbon age will end because humans will find more appropriate or cheaper alternative sources of energy rather than being subject to further arbitrary carbon taxes that generate revenue that is more likely to be used to try and address sovereign debt rather than facilitate the research and development of alternative sources of energy That's it. In the long run there are only two scarce resources. One is the span of human attention, the other is land area for neither one is subject to expanded reproduction. Both are overexploited. The first one by the unrestricted flood of commercial and political advertisement (in fact the most serious case of environmental pollution), the second one is by the so called renewable resource policy. Which in fact lays waste to huge expanses of land, either by installing useless, inefficient and ugly wind farms (on taxpayer's money, of course) or abusing it in other ways like solar collectors, flatland hydropower or fuel crops.
Anyway, you can do the math, renewable energy is absolutely insufficient to maintain the necessary energy supply to world economy, even in the short run.
Therefore decarbonization is nothing else but the end of the world as we know it. It's as simple as that.
As for carbon taxes, it would be a best case scenario to address sovereign debt. In reality carbon credit fraud (158,000 hits) is fast becoming the most popular creative business opportunity.
Of course, as I have already mentioned, there is a solution. Just overemotional greenies should be sent home first, who were careful to remove the only viable alternative energy source from public discourse before going for carbon en force.
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KR at 02:49 AM on 13 July 2010Hotties vs Frosties?
Ken's and BP's arguments seem to center on a reductionist approach, or at least the "solid science" approach generally used by people I will (IMO) label 'denialists'. Note - I want to talk about the tactics, not label people whose discussions have from time to time shown elements of these tactics. An issue (real or not) with a single piece of evidence does not invalidate an entire theory - it never has. Yet certain groups have frequently claimed this. For example: risks of acid rain, risks of smoking and secondhand smoke, the ozone hole, DDT, shortcomings of the Strategic Defense Initiative (SDI), and now climate change. Each scientific issue has been faced with shouts about singular issues, with the claim that any error whatsoever invalidates the entire issue. And oddly enough, everything I just listed is discussed here in "Merchants of Doubt, where the authors point out that exactly the same people (S. Fred Singer, Robert Jastrow, Willie Soon, and others) have been involved in almost every one of these issues. That's not a convincing track record! I have a family connection with denialists - my brother used to be one of the major public faces for a large tobacco company, denying the effects of second-hand smoke. A few months after he started that job he handed me a copy of "Thank You For Smoking", and said "This is my job - I AM Nick Naylor!" He used every one of the tactics above repeatedly - and every day political decisions were delayed meant money for his company. He never did tell us how much a soul went for, though... "Sound science", calls for absolute evidence (More study! More study!), and nitpicking individual pieces of evidence as 'proof' that entire bodies of science are invalid are all examples of 'denialist' tactics. The evidence is never 'absolute', but when a massive preponderance of evidence accumulates, we can certainly be sure enough to act! -
Peter Hogarth at 02:45 AM on 13 July 2010Sea level rise is exaggerated
daniel at 12:31 PM on 12 July, 2010 I suggested the tidal data barely fits into the 2 sigma envelope and does not fit anywhere except where it is using the 1 sigma curves. I have extended these up to point 1 for sake of argument only. You state “Mere opinion, show it with an overlay”. My statement stands.
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chris at 02:39 AM on 13 July 2010Hotties vs Frosties?
Albatross at 02:08 AM on 13 July, 2010 "Correct me if I am wrong but the trend in global mean sea-level rise is 3.0 mm/yr +/-0.4 mm/yr from Uni. Colorado. Or are they referring only to the contribution from thermal expansion?" That's the directly measured sea level rise from satellite altimetry. It encompasses the contributions from mass change (land ice melt) and ocean warming (thermosteric volume expansion). With the improving abilities to obtain independent measures of land ice melt (from monitoring glaciers and ice caps, and now from GRACE satellite estimates of regional mass redistribution from their effects on Earth's gravitational field) and thermosteric contributions (from direct measures of ocean heat changes), efforts have begun to attempt to do some basic "accounting" of the Earth heat and sea level budgets. The basic idea is that the independently determined mass contributions and heat contributions should sum to the directly observed sea level rise. Not surprisingly this is not straightforward, partly since the directly measured sea level rise (lowish uncertainty in this parameter) is the sum of two contributions of greater uncertainty (not to mention the potentially large contributions to sea level variation from internal fluctuations like El Nino and La Nina). Areas of uncertainty are very interesting! Scientists like them since they define arenas for potential discoveries. On the other hand they're catnip to those that like to insinuate that bits and pieces of data are incompatible with our broader understanding... -
apeescape at 02:30 AM on 13 July 2010Must-read article on ocean impacts by ocean scientists
Nobody seems to be linking to the Science articles (18 JUNE 2010 VOL 328, ISSUE 5985, PAGES 1437-1598) -
JMurphy at 02:21 AM on 13 July 2010Hotties vs Frosties?
Ken Lambert wrote : One wonders why we bother with measurements which give 0.8mm +/-0.8mm as evidence for SLR consistent with OHC rise. If you mean Leuliette & Miller (2009), it is only part of a host of measurements which, together, give a consistent picture. As they themselves state : While four years is a short period to interpret trends, the excellent agreement in observing systems demonstrates that the global ocean observing systems can be used to close the budget and verify the complementary observations. I know certain people like to pick out only one or two studies, out of the many, because they like what they see in them and then ignore all the rest, but it is always best to see what else is being said. How about more by Leuliette & Miller : here and here How about a round-up ((Contemporary Sea Level Rise) by Cazenave and Llovel : Recent results based on Argo show that since approximately 2003, thermal expansion is following a plateau (after correcting for instrumental drifts of some Argo probes: Early estimates of Argo-based thermal expansion, Lyman et al. 2006 showed a negative trend as of 2003; however, instrumental problems were subsequently reported on some probes, leading to cold bias, hence artificial ocean cooling). For the recent years, thermal expansion rates range from −0.5 ± 0.5 mm year−1 over 2003–2007 (Willis et al. 2008) to +0.4 ± 0.1 mm year−1 over 2004–2007 (Cazenave et al. 2009) and +0.8 ± 0.8 mm year−1 over 2004–2007 (Leuliette & Miller 2009). The 2003 data coverage is very sparse and it is likely that the Willis et al. (2008) value is biased low for that reason. The recent flattening of the thermal expansion curve likely reflects natural short-term variability. Similar short-term plateaus are also well visible in the past. Or another one from Trenberth. Anyway, these were all given by chris here (did you bother to go and read them ? The links I give should make it easier for you) and yet you still want to highlight one particular short-term measurement. Why ? What's wrong with the big picture ? Do you also highlight problems with the Theory of Evolution ? -
chris at 02:10 AM on 13 July 2010Hotties vs Frosties?
Ken Lambert at 00:07 AM on 13 July, 2010 Interesting, Ken. That illustrates quite a lot about certain approaches to science and knowledge, and especially efforts to misrepresent by focussing on minor areas of uncertainties. This entire thread started with a statement about context, and that (i.e. an informed consideration of context) would help you to understand, for example, the OHC measurement you refer to here: "One wonders why we bother with measurements which give 0.8mm +/-0.8mm as evidence for SLR consistent with OHC rise." Remember that that measurement was part of an analysis of the extent to which the sea level "budget" could be closed for a very short four year period [*]. Not surprisingly estimation of some the sub elements of this analysis (e.g. the thermosteric contribution to sea level) has a high uncertainty. That's obviously why we don't attempt to draw fundamental conclusions from analysis of very short time periods. What is the context in which it might be useful to determine an estimate of the thermostatic contribution at low precision, to a very short term period of sea level rise Ken? The answer is during a period following the introduction of new measurement technologies (ARGO for upper ocean heat measurement; GRACE for gravity perturbation based mass redistribution measurements). These analyses constitute an important initial test of the technologies and allow us to establish whether fundamental problems might exist (crudely put, if the sum of GRACE-derived mass contributions and ARGO-derived thermosteric contributions to sea level rise including error at 95% confidence overlaps with independently determined satellite-derived sea level rise, then we have confidence that there is nothing fundamentally problematic with the technologies and methodologies, although that doesn't prove that everything is working as well as we hope). So context is key. Obviously over the longer term the precision of our measurements improve (signal rises from noise as random measurement error and internal fluctuations average out). This (context) is where there are problems in your other statements: Peter: "each piece of evidence should be able to stand on its own right, irrespective of any support that may or may not come from another domain" (#40)." Ken: "That is a profound statement of scientific truth." Well it certainly sounds profound Ken, but I suspect it may be one of those rather empty assertions that dissolve away when considered in the light of real world observations. Can you give us a relevant example? For example one in the context of the current discussion. "When an accurate and repeatable measurement of OHC is available, then we will know the true extent of global warming or cooling." There's no question that good OHC data will fundamentally improve our ability to test our understanding to the Earth response to radiative imbalance. But global warming can also be defined in relation to the response of the Earth surface and since (a) this is the bit of the Earth we inhabit and have a profound interest in, and (b) this is the measure that allows us to assess the relationship between changes in radiative forcings and surface temperature response in the near and deep past, it would be foolish indeed to consider that we require OHC measures before we can properly assess global warming. Remember that uncertainty in little bits of sub issues doesn't drive out certainty in the more fundamental areas of our knowledge. For example we have high confidence that radiative imbalance results in sea level rise due to land ice melt and ocean warming. We can measure sea level rise reasonably well and the measurements generally correspond to our expectations. The fact that we can only make an imprecise direct estimate of the thermostatic contribution to sea level rise during the period Jan 2004 to Dec 2007 doesn't negate our higher level certainties. [*] Leuliette E, Miller L. 2009. Closing the sea level rise budget with altimetry, Argo and GRACE. Geophys. Res. Lett. 36:L04608 -
Albatross at 02:08 AM on 13 July 2010Hotties vs Frosties?
Ned, Phillipe et al., BP has repeated this figure on this thread, even though John Cook advised him here that he is comparing OHC for 0-3000 m with that from 0-700 m. That is not a valid comparison, and definitely not a valid reason to strongly assert that there are issues with the data. Someone else claims that "why we bother with measurements which give 0.8mm +/-0.8mm as evidence for SLR consistent with OHC rise" Correct me if I am wrong but the trend in global mean sea-level rise is 3.0 mm/yr +/-0.4 mm/yr from Uni. Colorado. Or are they referring only to the contribution from thermal expansion? I am all for people making the effort to understand and even to try and reproduce scientific findings. However, when our results do not agree with those in the literature, I would caution against making statements of data fudging or conspiracies. A much, much more plausible scenario is that we have made one or more errors. -
Riccardo at 01:37 AM on 13 July 2010Sea level rise is exaggerated
daniel, I'd not look for cutting edge research paper, it's just simple physics. Global sea level may rise due to thermal expantion of the ocean or to the melting of land ice; locally it may rise for a change in the ocean circulation pattern. It has nothing to do with AGW and the like. Add to this that even simple statistics would tell you that going from the lower to the higest end of the uncertainty range is statistically very unlikely. Beyond this, I might we willing to say that global sea level rose because of a rise of the ocean floor with respect to the continental crust or because of a giant movent of masses that locally produced an increased gravitational pull. In principle they are both possible, in practice they're both untenable. And this is also the line we should never cross if we want to talk about the science of any phenomenon instead of producing pseudo-scientific hypothesis. -
michael sweet at 01:32 AM on 13 July 2010Hotties vs Frosties?
Ken Lambert (and others) Your post at 102 suggesting that we do not know the extent of global warming because of uncertainty in OHC is extraordinary!! The claim that we must have every piece of the puzzle exactly in place in order to understand what the picture is has been used for decades by deniers to argue that we should not take action about global warming. In the 1990's they said that we needed to know surface warming. Look at Watt's pictures! Forget the confirming satalite data. Now that surface warming is known beyond resonable doubt (as described above by Ned) the deniers want OHC. Once that is known they will want advance, certain knowledge of sea level rise, confirmed prediction of all rain changes or some other obscure item. It will never be enough. "each piece of evidence should be able to stand on its own right, irrespective of any support that may or may not come from another domain" (#40). What a waste of space. Some data will never be as sure as other data. OHC is very difficult to measure and will have uncertainty for decades. It is the combination of mulitple lines of evidence that is convincing. How many times has John said that we must look at ALL the data and see the whole picture, rather than focus on a single uncertain item and say that is more important than all other data combined. -
ProfMandia at 01:04 AM on 13 July 2010Must-read article on ocean impacts by ocean scientists
Two more links from these two scientists written for the general public: John F. Bruno: The Impact of Climate Change on the World's Marine Ecosystems Ocean changes may have dire impacts on people - UQ News Online - The University of Queensland Scott A. Mandia, Professor of Physical Sciences Selden, NY Global Warming: Man or Myth? My Global Warming Blog Twitter: AGW_Prof "Global Warming Fact of the Day" Facebook Group -
PatriciaW at 00:56 AM on 13 July 2010Must-read article on ocean impacts by ocean scientists
It is unfortunate that the authors of this article still repeat the long since abandoned target of under 450ppm. They also do not mention the effect on the planet's oxygen supply which ocean acidification will probably cause if it kills off oxygen generating phytoplankton. (I've also added this comment to the original article.)Response: Re oxygen, I'd hazard to guess John and Ove were doing the same thing I tend to do with my articles lately - hit the broad points and let the nitty gritty come out in the comments. In science writing, it's tempting to throw everything in there but effective communication requires you discipline yourself to the major points lest your message get diluted with too many details. -
daniel at 00:16 AM on 13 July 2010Sea level rise is exaggerated
Riccardo at 00:00 AM on 13 July, 2010 Well actually I would question whether your claim that SLR is so strongly linked to the percieved warming of the 20th century or if the temperature record is so reliable into the past, both over this period and beyond. But since this is a pro AGW website it is up to people like myself to disprove the unproven. Are there any papers you rely on Riccardo to undoubtedly satisfy yourself of SLR driven strongly by climatic factors and also the reliability of the reconstructed temperature record? Post a link and we'll discuss it. I've only just started to find some time to read some of Peter's links throughout the above discussion.Response: Might I suggest starting with Vermeer 2009 that examines the link between sea level rise and temperature, finding the two are closely linked:
Observed rate of sea-level rise (red) compared with reconstructed sea level calculated from global temperature (dark blue with light blue uncertainty range). Grey line is reconstructed sea level from an earlier, simpler relationship between sea level and temperature (Vermeer 2009).
Of course, where the paper gets really interesting is when it uses these results to predict future sea level rise which we examine here... -
Ned at 00:11 AM on 13 July 2010The Dunning-Kruger effect and the climate debate
Mr_Obvious, it would help if you'd give some specifics -- when you just write "[t]he various posts above seem to abound with seemingly objective; but, in many cases, clearly slanted view points" it's difficult for anyone to respond meaningfully. Which post seems slanted, and how? The one specific fact you mention in your comment is By the way, something I noticed long ago, and posted on on a number of forums; but, have get to get a well validated response to: O2 and CO2 have nearly the same IR absorption spectra / levels. Why is O2 not considered a green house gas when CO2 is? I'm not sure where you are getting that from, but the absorptance spectra of CO2 and O2 are entirely different. Check out the bottom panel of this figure:
Note the CO2 absorptance peak ~13+ micrometers, within the range where the Earth surface radiates and the atmosphere is otherwise semi-transparent.
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Riccardo at 00:10 AM on 13 July 2010Temp record is unreliable
Ned, sometime I think that whatever the amount of data one can provide there's no way to convice some, hopefully just a few, guys. Nevertheless, it's always worth trying and keep all of us up to date with these new findings. Thanks. -
Ken Lambert at 00:07 AM on 13 July 2010Hotties vs Frosties?
BP, JMurphy, kdkd "each piece of evidence should be able to stand on its own right, irrespective of any support that may or may not come from another domain" (#40). That is a profound statement of scientific truth. I have found BP's contributions very informative and obviously backed by a serious amount of work. I agree with much of his analyses. The OHC issue is critical to the whole theory of AGW by the enhanced CO2GHG effect. One wonders why we bother with measurements which give 0.8mm +/-0.8mm as evidence for SLR consistent with OHC rise. When an accurate and repeatable measurement of OHC is available, then we will know the true extent of global warming or cooling. -
Riccardo at 00:00 AM on 13 July 2010Sea level rise is exaggerated
daniel, step by step things are getting clearer in my opinion and your last graph is very helpful. Now, in light of this new graph, could you tell what should drive these sudden accelerations in the past? Known science can tell just for the last one, the one in the last century, it's mainly ocean thermal expansion and land ice melting. It's up to who's trying to cast doubts on the accepted explanation to provide evidence and reconcile it with other data that support his hypothesis. -
Ned at 23:04 PM on 12 July 2010Hotties vs Frosties?
I admit I haven't been following this thread, partly because I've been traveling and partly because I'm not all that interested in these kinds of "meta" discussions. But I was surprised to discover that Berényi Péter is still making incorrect allegations like this: Furthermore, there is the (not well advertised) issue of different adjustment procedures being applied to US data and the rest of the world. The differences in processing between the USHCN and non-US stations in GHCN are discussed in many places, including in the primary description of the GHCN v2 data set, right here: Peterson, T. and R. Vose. 1997. An Overview of the Global Historical Climatology Network Temperature Database. Bulletin of the American Meteorological Society, 78(12): 2837-2849. Less than two weeks ago I pointed this out to BP in another thread, where he was discussing the same issues: Are surface temperature records reliable? I suppose he must have stopped following the discussion there and then decided to bring it up again here. In any case, it is completely wrong to suggest either that the GHCN data are "tampered with" or that the difference in adjustments between USHCN and GHCN is "not documented" (his emphasis). He appears to have never bothered to read even the basic introductory paper about GHCN (Peterson and Vose 1997) before flinging around accusations of "tampering". I would urge people to go back and reread the discussion of this issue in the previous thread. I'd also urge people to keep the following in mind: * The net effect of the GHCN adjustment is small, slightly increasing the trend in the early 20th century but actually decreasing the trend over the past three decades. As I wrote in the other thread: Using a gridded analysis, the actual difference in the trends is 0.04 C/century over the last 90 years. Over the last 30 years, the difference in trend between the raw and adjusted data is 0.48 C/century ... with the adjusted trend being lower than the raw trend. In other words, the "tampering" that BP has detected is, over the past 30 years, reducing the magnitude of the warming trend. * The unadjusted data are available and can be (and are) used in many of the new, independent temperature reconstructions. * You cannot evaluate the actual effect of the GHCN v2 adjustments on the global temperature trend without using some form of gridding or other method to compensate for spatial dependence in the adjustments themselves. Again, as discussed in the other thread, Treating the rest of the world as homogeneous will not yield an unbiased estimate of the global mean adjustment unless either (a) the stations are distributed approximately uniformly in space [and] time, or else (b) the expected value of the adjustment for station X in year Y is independent of that station's location. * Land represents only 29% of the earth's surface, so any artifacts present in the GHCN data (due to adjustments, UHI, or anything else) will have only a small impact on the global trend as a whole. * Finally, surface temperature analyses using GHCN (whether adjusted or not) are generally similar to those based on satellite measurements of the lower troposphere. In addition, a new analysis by Ron Broberg and Nick Stokes shows that the GHCN temperature trends are virtually identical to those from a completely different surface data set based on GSOD. The GSOD data include a larger number of stations, better coverage of the Arctic and other remote regions, and no decline in station numbers in recent years. At this time, there is really very little point in arguing about the surface temperature trends. They've been confirmed over and over again; none of the various criticisms leveled at them has been shown to have any substantial impact at all on the final outcome. -
JMurphy at 23:04 PM on 12 July 2010The Dunning-Kruger effect and the climate debate
Mr_Obvious wrote : Hanson was a good example of having credentials, being well respected, and getting it wrong, repeatedly. Well, that statement may seem like an obvious fact to you but could you at least back it up with some examples, please, for those of us who don't just accept that claims are the same as facts ? -
Mr_Obvious at 22:37 PM on 12 July 2010The Dunning-Kruger effect and the climate debate
Just an after thought follow up. Credentials do not in and of themselves guarantee wisdom, understanding, or even an applicable skill set. Hanson was a good example of having credentials, being well respected, and getting it wrong, repeatedly. Gore can be more easily written off as he has no real credentials; yet, Hanson was just as far off as Gore, who based his movie - in part - on Hanson's predictions. -
Ned at 22:24 PM on 12 July 2010Temp record is unreliable
Ron Broberg and Nick Stokes have created an entirely new gridded global surface temperature analysis that is independent of GHCN. It is based on the Global Summary of the Day (GSOD) records for a very large number of stations, available here. The main advantage of this is that it provides a semi-independent confirmation of the GHCN-based analysis that has been used for most of the surface temperature reconstructions up to this point. Other advantages include a larger number of stations, more stations in the Arctic and other remote locations, and no decrease in station numbers in recent years. Ron developed tools to acquire and reformat the GSOD data, and Nick then ran it through TempLS, his global temperature analysis program. The results are very similar to those from previous reconstructions using GHCN:
Over the past three decades, both data sets (GHCN and GSOD) show similar trends (+2.5C/century) in Nick's analysis.
If you find this all a bit confusing, the bottom line is that this is a radically new way of confirming the reliability of the existing surface station temperature analyses from GISSTEMP, HADCRU, etc.
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Mr_Obvious at 22:22 PM on 12 July 2010The Dunning-Kruger effect and the climate debate
It seems The Dunning-Kruger effect is alive and well on both sides of the debate. And the CO2 levels remain an example even now, and to, at least some extent, perhaps, may even be effecting the author of this article. The various posts above seem to abound with seemingly objective; but, in many cases, clearly slanted view points. In nearly every post (including the article) some, often obvious, detail was omitted that might have impacted the conclusion. Perhaps we could all take some extra time to refine our thoughts and triple check our facts before posting. By the way, something I noticed long ago, and posted on on a number of forums; but, have get to get a well validated response to: O2 and CO2 have nearly the same IR absorption spectra / levels. Why is O2 not considered a green house gas when CO2 is? (If your planning on making the narrow band argument, please have something verifiable to back it up) -
CBDunkerson at 22:09 PM on 12 July 2010Hotties vs Frosties?
Geo Guy #94 wrote: "...and yet we can emphatically state that AGH's [sic] are THE driver to rising global temperatures??...I think not." 'THE' only driver? No. 'THE' most significant driver? Based on both the paleoclimate record and measurements of current warming I don't see how anyone can dispute it. We can see from the paleoclimate record that major warming and cooling shifts have continuously corresponded with GHG shifts. We can measure GHG and radiation changes and compute (not guess, not model, not estimate... but compute from proven values and formulae) that they account for most of the measured warming observed thus far. In short, we know that CO2 is the primary driver of current warming because we can do math; Even most 'skeptics' now seem to accept that a doubling of CO2 by itself would cause about a 1 C (actually just under) increase in global temperature... this is computed from the measured radiation absorption spectrum of CO2 and the formula Arrhenius came up with over a century ago. If that is taken as accepted, as all but the extreme fringe of skeptics seem to agree, then we can compute expected 'GHG only' warming for other CO2 levels; In 1998 the CO2 level was 365 ppm, but with changes in other GHG levels factored in the 'CO2 equivalent' was 412 ppm. The historical level generally used is 278 ppm. Thus, IF 'x*ln(576/278) = 1 C' (i.e. 1 C increase from CO2 doubling) THEN, 'x*ln(412/278) = 0.57 C' The measured warming through 1998 was about 0.75 C above what it was back when GHGs were at 278 ppm. Thus, 76% of the observed warming can be explained by the warming we know the increase in GHGs should have caused. That makes GHGs the primary (76%) driver of the observed warming... and the remaining 24% shows that feedback effects have been positive, not negative. We only then get into models with the expectation that feedback effects will accelerate as time goes by and estimating the end result. This is why you no longer find 'skeptic' scientists claiming warming of less than 1 C for a doubling due to negative feedbacks... we KNOW net feedbacks are positive. The only remaining refuge of 'skepticism' is that these net positive feedbacks will be less than the majority of scientists believe. Disclaimer: The math above is greatly simplified in that it computes temperature anomalies directly rather than radiative forcings and then the temperature anomalies those would cause AND ignores changes in atmospheric density as composition changes (which would only be significant for MUCH greater atmospheric changes than we are looking at and would then lead to MORE warming). That said, it's precise enough for illustrative purposes... most of the observed warming is due to GHG increases. -
Berényi Péter at 20:31 PM on 12 July 2010Hotties vs Frosties?
#87 Philippe Chantreau at 01:44 AM on 12 July, 2010 The point was not about the data, it was about your attitude. Stop ranting about my attitude, please and let's focus on data instead. If you show my reasoning to be faulty by uncovering the specific error, I am quite ready to accept it. On the other hand if you try to find flaws in my attitude, that gets us nowhere. BTW, your attitude of surmising an error is something to be ashamed of instead of to be corrected is highly questionable. At least I refuse to take this attitude as a valid and fruitful one. What about actually doing some work by trying to understand things on your own? It would have the advantage of promoting public understanding as well. -
daniel at 20:01 PM on 12 July 2010Sea level rise is exaggerated
To Riccardo #89 Ok Riccardo again I'l answer a bit more directly. Do we have any real evidence that the 1mm/yr trend existed without short term variations from the paleo data? How can we know if drivers existed or not when the links of SLR to temperature fluctuations are so poorly achieved using paleo data? What do other data sets say Riccardo? Post some links we can discuss it. Here's a graph of Donnelly's data with sample 11 reassigned to the younger date range which was never adequately constrained by Donnelly in the first place. (But he was happy to fit the older date range to suit his trend).
Are you sure it's not possible for the recent sea level trends, or very similar slightly less severe uptrends, to have existed in the past given the uncertainty in the paleo data? Does this make the recent uptrend look less alarming? Is all of pro AGW science done this way? You wanna discuss drivers? Post some links.
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MP at 18:37 PM on 12 July 2010Hotties vs Frosties?
John Brookes @ 96 “Thanks for the comments. I don't favour delay. I would like to see a carbon tax implemented now, and steadily increased. Only if the weight of evidence starts to turn, would I want the carbon tax to be removed.” One has to question whether this is the most appropriate and robust strategy in terms of being applicable to more than one possible scenario. In this regard, it would appear that the different possible scenarios for climate change that have been advanced by various interest groups can essentially be simplified as being: 1. Continual warming with no prospect of a further glacial period; 2. Warming in the short to medium term before the onset of cooling that precedes a new glacial period; 3. Temperature equilibrium in the short to medium term before the onset of cooling that precedes a new glacial period; and 4. Cooling in the short term to medium term preceding the onset of a new glacial period. Both continual warming and the onset of a new glacial period in the future will have a significant impact on the sustainability of the human population which is already being impacted by a shortage of resources, particularly food, water and energy, to even meet basic needs let alone the lofty goals of narrowing the disparity in global living standards which is becoming an increasing source of conflict. Based on the premise that GHGs are contributing to warming, it is evident that attempts to control one of one of these gases, CO2, via the suggested further carbon tax (carbon taxes already exist, i.e in many countries petroleum products are currently heavily taxed) is only applicable to addressing scenario 1, as the impacts from another glacial period outlined in scenarios 2 to 4 could be beneficially mitigated by the warming afforded by GHGs. In addition, within the context of the dynamic natural processes affecting both the earth and the universe, as no one appears to have been able to accurately determine the appropriate level of CO2 in the atmosphere for the earth’s current and future situation, one must pose the question, what happens if we get it wrong and we create a reverse tipping point by reducing too much CO2 and accelerate the onset of the next glacial period? Within this context, the most robust strategy that is able to respond to the four possible scenarios of climate change and the inability of the earth’s resources to currently provide every human being with a globally accepted living standard, sadly remains placing limits on population growth. It is contended that this strategy could even be more effective in reducing CO2 than the proposed carbon tax due to the cumulative impact of a reduction in the demand for goods and services and governments would still have the option to review and relax controls to order to respond to changing circumstances in the future, and even increase CO2 emissions to mitigate the effects of a new glacial period should the weight of evidence suggest this to be necessary and appropriate. Finally, just as the Stone Age ended, not because the earth ran out of stone or a stone tax was introduced, the carbon age will end because humans will find more appropriate or cheaper alternative sources of energy rather than being subject to further arbitrary carbon taxes that generate revenue that is more likely to be used to try and address sovereign debt rather than facilitate the research and development of alternative sources of energy. -
JMurphy at 17:57 PM on 12 July 2010Hotties vs Frosties?
Geo Guy wrote : As scientists we must continually question the “status quo”. If we stop doing so, our understanding of science will cease to evolve. Hence despite what the “science” may tell us, there is a definite role for taking a contrarian position. Science is rarely definitive. The application of science is what changes over time and is the basis upon which we evolve as a species. So, Creationism (which continually questions the status quo, takes a contrarian position and likes to show that the Theory of Evolution is not definitive) is a valid position to take, is it ? Perhaps the answer lies "somewhere in the middle" - we're not talking about "irrefutable proof" after all, are we ? -
daniel at 16:33 PM on 12 July 2010Sea level rise is exaggerated
Riccardo at 16:26 PM on 12 July, 2010 You tell me. Donnelly can't. -
Riccardo at 16:26 PM on 12 July 2010Sea level rise is exaggerated
daniel, here the discussion becames circular and I can only repeate what i wrote in #78. Do we have any evidence of such "short" (one century and a half) term variations in the past or are they just hypothetical? What should have produced these accelarations? What do other datasets say? -
John Brookes at 14:37 PM on 12 July 2010Hotties vs Frosties?
owl905 @79 - Thanks for the comments. I don't favour delay. I would like to see a carbon tax implemented now, and steadily increased. Only if the weight of evidence starts to turn, would I want the carbon tax to be removed. I do favour civilized debate. As I said in a comment above, there is no point in assuming that people with opposing views to your own are arguing in bad faith. Some are, but you won't sway them. Rather than polarise people into the two camps of hotties and notties, I'd like to think that there is a third camp who are more interested in finding out exactly what is going on. There is of course a 4th camp, by far the biggest, which is people who don't know, and are smart enough to know they don't know, and who will leave it to others to work it out. These people will decide elections and policy. I think it is unwise to tell such people, "If you aren't with us you are against us". Faced with a perceived need to take sides, they might go all notty on us. For these people, the precautionary principle (you could take a chance and bet that all those scientists are wrong...), together with reassurance that the change to a low carbon economy will not be the end of the world as we know it, should be enough to see them support action. Trying to "prove" that global warming is real and dangerous could be counter productive. If they have kids, they might like to think of their future - after all, parents will happily incur the large financial penalty of private schooling in the hope that their kids will have a better life. A much smaller investment in the environment would seem like a sensible thing to do. -
scaddenp at 14:22 PM on 12 July 2010Hotties vs Frosties?
geoguy - the point about drivers is not that we know them but that you cannot have proof in science. Testing models against data is at the heart of science. I really dont know how else you pursue the subject. (Not that I think anything "new" about cosmic radiation or ocean currents has changed any picture of the earth heat budget). The models are very good at not only predicting temperature but also the pattern of warming - and they spring from a basic physics. A conclusion that 3.7Wm/2 of radiative forcing is NOT going to cause warming requires some as yet undiscovered negative forcing. Is this measurement of GHG forcing not direct enough for you? Oh and models in the scientific sense ARE the theory. The computersdo the numerics for the model. If comparing their prediction to data is not the way to test the model, then what is? I am not really sure what point you are trying to make with the Jun paper. But for further analysis on the use of model ensemble, see Annan et al "Consequently you have every reason to reject the model if you are wanting to come to a specific conclusion. " This statement just does not make sense. Please lets hear your alternative theory of climate that is making better predictions. Some numbers not hand-waving would be good. -
Geo Guy at 13:38 PM on 12 July 2010Hotties vs Frosties?
scaddenp - # 91 - knowing the drivers is one thing; knowing completely how they interact with one another to affect our climate is another. We are learning new things about our sun each day, the sun that sends the heat to earth. We are also learning new things about cosmic radiation and how it affects our climate. We know that ocean currents are a big determinant of climate yet we do not fully know to what extents. We know that episodes of el Nino and el Nina have profound effects on global temperatures yet we do not fully comprehend how those episodes occur...and yet we can emphatically state that AGH's are THE driver to rising global temperatures??...I think not. Models tend to have their own built-in bias. http://www.stat.tamu.edu/~mjun/paper/A06624R1.pdf Furthermore models are only as good as the input parameters, including the interaction of parameters that drive our climate. Models are not proof of a theory, only evidence how the theory may act under specific parameters. Consequently you have every reason to reject the model if you are wanting to come to a specific conclusion. -
johnd at 12:51 PM on 12 July 2010An account of the Watts event in Perth
JMurphy at 08:12 AM, the correct terminology should probably have been "reappeared" as technically I understand they first "appeared" in Perth enroute to their scheduled presentation at Narrogin the previous day. It's a small point but in the spirit of the precision being demanded, perhaps a valid one. ;-)
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