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thepoodlebites at 03:05 AM on 7 July 2011Increasing CO2 has little to no effect
#51 KMurphy Ulterior motives? Surely you're joking Mr. KMurphy. Justed wanted to access precisely what scaddenp referenced, so there would be no misunderstandings. I'm now visiting the website now, for the first time. Wow, what big error bars you have, +-0.4C. -
thepoodlebites at 02:51 AM on 7 July 2011Increasing CO2 has little to no effect
#50 belay my last: too many nots, sorry. My guess is that the model temperature predictions based on CO2 rise alone will not match the observed temperature record since 2000. If that is the case then the radiative forcing components that Meehl used in 2004 were not accurate and that forcing from natural climate variability has not been properly accounted for. Or to put it another way, the temperature record for the last decade can not be reproduced in the model with anthropogenic forcing alone. -
skywatcher at 02:33 AM on 7 July 2011Climate's changed before
Turns out I'm not first with the word (bah!) - a google search on 'climastrology' comes up with all sorts of nasty anti-Gore, anti-science stuff. But I would certainly say it fits very well for people who think they can predict climate using some flavour or combination of 'cycles' rather than the well-understood and well-verified radiative physics, just like your example Sphaerica. -
ranyl at 02:31 AM on 7 July 2011Over the tipping point
Wonder what weather changes the rapid loss of arctic summer ice will bring?
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Philippe Chantreau at 02:23 AM on 7 July 2011The Last Interglacial - An Analogue for the Future?
That's a very long and wordy post that seems to be tending in the direction "we don't know" and "it's natural cycles", although this is actually not clearly stated nor defended in the post. I'm sure some will find your mini lecture on D.O. events informative but there are better sources for that. The same applies to the other types of events mentioned. I'll restate that there has not been a D.O. event in over 20K years. The periodicity of Bond events has not been established. Bond argues of approximately 1500 years, +- 500 years. It is not clear whether there actually is a cycle. If the timing of Bond event #1 is correct (450AD), then another should be underway now, or should be/have been, anywhere between 500 years ago and 500 years from now. But how much would that concern us? It is possible that the LIA was a Bond event (they are cold episodes), but perhaps it was not. If it was, it would confirm the lack of a global character of these events. The vast majority of them do not correspond to any clear climate signal, especially on a global scale. There is little indication that the LIA was a global event. Milliken, for instance, failed to find a clear signature for it in the SHALDRIL cores. I find that these purported cycles are of little to no relevance to the current warming event. I don't see how you demonstrate otherwise. -
dana1981 at 02:18 AM on 7 July 2011Lessons from Past Climate Predictions: Syun-Ichi Akasofu
thanks CBD, figure numbering corrected. I agree, "LIA recovery" is one of my favorites because it's just so ridiculous, like the climate just bounces around some natural equilibrium for no apparent reason. As I noted in the rebuttal to "LIA recovery" linked in the post, the factors which caused LIA cooling are not currently causing warming, so again, it's a completly unphysical argument. -
dana1981 at 02:15 AM on 7 July 2011Lessons from Past Climate Predictions: Syun-Ichi Akasofu
rand15 - you're free to object, but the fact is that Akasofu's prediction is not based on physics at all. "Recovery from the LIA" is not physics. Akasofu did not even attempt to identify the physical cause of the warming trend, other than a throwaway reference to cosmic rays in the published version of the paper. -
CBDunkerson at 02:14 AM on 7 July 2011Lessons from Past Climate Predictions: Syun-Ichi Akasofu
You've got two items labelled as 'Figure 4'. Last two images should be changed to 'Figure 5' and 'Figure 6'. I always love the 'recovering from the Little Ice Age' explanation... as if it were completely reasonable to identify an effect without a cause. -
Steve Brown at 02:12 AM on 7 July 2011The Last Interglacial Part Two - Why was it so warm?
#9 - The paper you link to just provides further confirmation that some regions had continental climates during the Eemian due to the orbital configuration and Arctic sea-ice / albedo feedback. I touched on this in Part 1 of the series. I'm afraid it doesn't provide any support for #1. -
_rand15_ at 02:03 AM on 7 July 2011Lessons from Past Climate Predictions: Syun-Ichi Akasofu
@dana1981 [dana1981] No you're missing the point. Akasofu's prediction is inaccurate because it's not based on physics. I really object to this notion. A prediction can be perfectly accurate without being based on any specific theory. And a prediction can be inaccurate even though based on "physics", if it is based on a faulty analysis or if some important factor has been omitted. Should a prediction turn out to be inaccurate, you can then say "oh, well, what do you expect? It wasn't based on physics." Should it turn out to be accurate, then you want to find out why, which may be coincidence or may be new physics, or previously overlooked factors. -
JMurphy at 01:29 AM on 7 July 2011Increasing CO2 has little to no effect
thepoodlebites wrote : "When you get a chance, can you please point me to RC’s regularly updated model-data comparisons?" You obviously have some ulterior motive for asking that because a few seconds of searching found this, up to the end of 2010 : Real Climate 2010 updates to model-data comparisons Were you looking for something else ? -
BBD at 01:27 AM on 7 July 2011A Detailed Look at Renewable Baseload Energy
CBDunkerson 1) Shutting down nuclear plant if there are demonstrable safety concerns is a Good Thing. In the wake of Fukushima, this may accelerate, and that would be a Good Thing too. What is not a good thing is when arguments based on accidents at old plant (Chernobyl and Fukushima) are used to try and prevent construction of Generation III plant. That's illogical. Remove logic and what is left? 2) See #96.SEGS: - 1,600 acres of the Mohave - best insolation in US - Capacity 354MW - Output (unverified) 75MWe - Load factor 21% See the problem? You aren't going to power the planet with solar. It's wishful thinking.
You did not respond. The footprint of low-density energy technologies is a serious constraint on solar and wind. Interconnectivity and security of same over wide areas is another (even for the US, long-distance HVDC interconnectors represent a security of supply risk). Variability is another. See also Mark Harrigan at #171. Actual insolation is another (thanks again, Mark Harrigan; you said it for me). We've been through the European DESERTEC handwaving upthread. It was not resolved satisfactorily eg #81 ff. You say:The fact that one power company says it does not make it true.
Well, who do we listen to? The chief exec of E.ON UK (and every other energy expert who says the same), or you? Especially since your response rests on SEGS, which as MH has helpfully pointed out, is an irrelevance for the UK. Solar is an irrelevance at mid/high latitudes generally. Huge pumped hydro resources are the best bet, but you are in trouble if they do not exist and you are forced to engineer them. Again, we've been through all this earlier in the thread. At what point do proponents of renewables finally concede that their case is actually weak and unpersuasive? Perhaps after reading the critiques of Jacobson & Delucchi? -
Mark Harrigan at 01:23 AM on 7 July 2011Lessons from Past Climate Predictions: Syun-Ichi Akasofu
If you are a Scientific American subscriber you might want to look at this article from July Scientific American Paleocene-Eocene Thermal Maximum (actually the link works even if you're not a subscriber) which reports a new study from this period that shows how over a period of about 20,000 years natural events contributed to huge greenhouse gas emssions that raised global temps by almost 8 degrees C. Have a look at the graph on the 4th page of the article. It draws a precise analogue with the amount of CO2 we are injecting into the atmosphere today in a tiny fraction of that time. If we keep doing business as usual it suggests if anything current warnings are a gross UNDER estimate of what might happen. Worth a Read - and very sobering. So denialist models like Akasofu's be damned - here is solid evidence what happens if the CO2 levels go up like they are -
thepoodlebites at 01:12 AM on 7 July 2011Increasing CO2 has little to no effect
#49 scaddenp So the statement “model parameters can be adjusted to match any set of temperature observations" is not true? I don’t consider “put up or shut up” or “do it yourself” as compelling arguments in a debate on the scientific issues. And for the record, I have never said that CO2 is irrelevant. The question remains climate sensitivity to CO2 rise. I was specifically addressing the radiative forcing components that Meehl used. The conclusion that “the negative and positive forcings are roughly equal and cancel each other out, and the natural forcings over the past half century have also been approximately zero” to be extremely convenient. So if “radiative forcing from CO2 alone gives us a good estimate as to how much we expect to see the Earth's surface temperature change,” why not run Meehl’s 2004 model again with the same forcings and include observations from the last decade. My guess is that the model temperature predictions based on CO2 rise alone will not match the observed temperature record since 2000. If that is the case then the radiative forcing components that Meehl used in 2004 were not accurate and that forcing from natural climate variability has not been not properly accounted for. Or to put it another way, the temperature record for the last decade can not be reproduced in the model with anthropogenic forcing alone. When you get a chance, can you please point me to RC’s regularly updated model-data comparisons? -
Eric the Red at 01:01 AM on 7 July 2011Lessons from Past Climate Predictions: Syun-Ichi Akasofu
cynicus, I agree that including a new average is inconsistent. The 5-year moving average (centered around Jan., 2000) shows a very slight decline from 0.43 in 2000 to 0.41 today (5 years averaged around Dec., 2008). The CRU 5-year moving average reached a maximum of 0.46 in mid 2004. Since the most recent moving average is only tabulated to the end of 2008, Figure 5 is quite accurate so far. Any claims of an inaccurate prediction are premature. We need to wait another few years to see if it holds.Response:[dana1981] No you're missing the point. Akasofu's prediction is inaccurate because it's not based on physics. As I noted in the article, even if Akasofu gets lucky and his prediction turns out to be close to the actual temperature change, it won't be because he was right, it will be because he was lucky.
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Bob Lacatena at 00:43 AM on 7 July 2011Climate's changed before
176, skywatcher, 177, les, Climastrology I like it. It's actually better than mathturbation, and more appropriate (in that mathturbation is clearly an important "skill" needed by climastrologists, but doesn't describe the overall, full version of alchemy in which they indulge). I'd personally like to recommend that we begin using the word where ever it applies... today's post by Dana on climastrologist Syun-Ichi Akasofu being a perfect case. -
DSL at 00:38 AM on 7 July 2011History Matters: Carbon Emissions in Context
Daisym, you don't really want a number, do you? There are plenty of numbers out there. I suspect that you'll argue with the basis of whatever number you get--argue to the point of convincing yourself that it's not accurate enough. But this is not about getting what you pay for. It's about paying for what you already have. This is a problem that extends beyond the average lifespan of an individual human. That makes it fair game for middle-class denial. After all, why should you personally pay for something that will primarily benefit future generations, living long after you're ashes or in a box in the ground? Why? If your morality is based on social justice and general human welfare, the answer is obvious. However, if your morality (or perhaps ethics in this case) is based on contracts and market responsibility, then you are now confronted with two problems. One, your current quality of life is largely based on over a century's worth of cheap fossil fuel use. All of the debt that can be paid for this use (setting aside the quite serious post-colonial reparations argument) is and has been paid, excepting one critical externalized cost. Aerosol pollution is an externalized cost that is being and has been paid for through regulation and the resulting market mechanics, and you'll probably agree that life is better without lead, SO2, and mercury raining down on us, even if we can't place an accurate number on the benefits. CO2 is the external cost that has not been paid for, has never been paid for. We've been cranking it out for the last century, and no one has taken responsibility for it. Ultimately, you'd have to agree, the responsibility lies with us to clean up the mess our irresponsible ancestors left us. They've given us wonderful things, but there's a skeleton in the closet--and it's beginning to move, and it has a baseball bat in its grip. That leads us to number 2: if you decide to pass on the responsibility, then you become irresponsible. If you decide to continue with business as usual, refusing to recognize the CO2 external cost, then you are buying something without fully paying for it. Basically, the modern world has had a free lunch for a century, and you're now being asked to pay for it. And now you want the same free lunch and want to make my grandchildren pay for it? Nope. And the longer the check remains unpaid, the more expensive it gets. -
Bob Lacatena at 00:31 AM on 7 July 2011Antarctica is too cold to lose ice
5, Steve, Just to highlight the obvious to anyone, in case it's not... what all of this means is that the IPCC AR4 underestimated sea level rise, because it counted on a negative rather than a positive contribution from Antarctica. This means that things are, once again, worse than expected, and the IPCC was too conservative (= non-alarmist) in its projections. -
cynicus at 00:19 AM on 7 July 2011Lessons from Past Climate Predictions: Syun-Ichi Akasofu
Dana, why are you changing from HadCRUT to WoodForTrees Index during the article while Akasofu uses HadCRUT? As a sidenote: HadCRUT does show 0.05°C warming over the 2000-2011 period although I immediately add that only 10 years of temperature data is way too short to have confidence in this linear trend. Also, HadCRUT does not include the Arctic which might cause it to underestimate the (warming) trend. But my main point is that I think you should stick with a single record throughout the article next time to maintain consistency. Or have you choosen the WfT Index because you think it is more accurate (if so, do you have a link to a discussion about this)?Response:[dana1981] Using HadCRUT is a cherrypick. It shows the least amount of warming since 2000 because it excludes the Arctic. Frankly I'd prefer to use GISTemp because I think it's probably the most accurate, but then 'skeptics' would accuse me of cherrypicking as well. I chose the WfT Index because it's a composite of the four most popular global temp datasets. Using a composite eliminates all accusations of cherrypicked datasets.
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Mark Harrigan at 00:15 AM on 7 July 2011A Detailed Look at Renewable Baseload Energy
@ CBD #170. I really don't think your rebutaal of BBD at #169 stands scrutiny. 1st because the example he is talking about is Wind as a reliable renewable and your example of SEGS is solar (CST). Second I'd like to see evidence that SEGS can provide baseload 24/7 for 365 because I don't think it can yet, The link on this site SEGS performance suggests it can only operate reliably for 65% of the year - that doesn't really cut it? But if you can source a link that shows otherwise would love to see it - so I would like to challenge your "Only 10% of the baseload power it supplies comes from natural gas backups" figure? It doesn't seem credible to me? (happy to be proven wrong though) finally - BBD is talking in the context of the UK - where solar is not nearly so viable an option and wind is the "viable" UK alternative. So, really, I think you are comparing your apple with his orange and the comparison is flawed (not to mention that I think your apple is a little bruised by exaggeration) -
les at 00:03 AM on 7 July 2011Climate's changed before
176 - skywatcher... "climastrology" :-D Tamino should add that to this discussion. Anyway, I have the strong suspicion that 174 is spam... but if you get a reply, it's probably because Mars is exerting a strong influence. -
Arkadiusz Semczyszak at 23:35 PM on 6 July 2011The Last Interglacial Part Two - Why was it so warm?
Interesting facts to prove what is written in a post 1. The Inconvenient Skeptic; I found here: Evolution of the seasonal temperature cycle in a transient Holocene simulation: orbital forcing and sea-ice, Fischer and Jungclaus, 2011. -
John Bruno at 23:31 PM on 6 July 2011Great Barrier Reef Part 1: Current Conditions and Human Impacts
Fair point DLB. It is a tricky subject, due in large part to the fact that the science budget for biological monitoring is a tiny little fraction of what is spent to monitor physical parameters. The evidence that has really persuaded me is recent - sadly as yet unpublished - work in John Pandolfi's lab at UQ: they are finding lots of evidence of coastal reefs that were buried by sediment around the time Queens was deforested. -
skywatcher at 23:29 PM on 6 July 2011Climate's changed before
#174: would it be like these 60-ish year and non-significant fluctuations, discussed by Tamino? There's a good discussion of periodicity and the detection of cycles within. People can pretend that the world's climate is driven by something nicely uncontrollable like planetary movements (climastrology?), but back in the real world, it's the radiative forcings that dominate, and the biggest forcing factor is indeed 'controlled' by humans. -
CBDunkerson at 23:18 PM on 6 July 2011A Detailed Look at Renewable Baseload Energy
Tom Curtis #152: I agree that it's a Catch-22: They can't get newer power plants built because of public fears over accidents at outdated power plants... and they can't shut down the outdated power plants because they can't get new ones built. However, that's the reality and the only way they are going to break out of the cycle is to shut down those older plants. Yes, they lose their revenue stream in the short term... but then have the opportunity for much greater revenues in the future. BDD #169: The fact that one power company says it does not make it true. Again, SEGS. Largest solar plant in the world. More than 20 years old. Only 10% of the baseload power it supplies comes from natural gas backups. Ergo, E.ON's claim that renewable energy can't provide baseload power without 90% fossil fuel backup is directly contradicted by established reality. -
Dikran Marsupial at 23:06 PM on 6 July 20112010 - 2011: Earth's most extreme weather since 1816?
Eric@276 All of the indices are correlations between actual observations and the downscaled results from the GCM runs, so all are comparing the model with reality. While pav and pint are indeed "merely daily rainfall", flood events in most parts of the UK are multi-day events, so the ability to predict day-to-day rainfall is actually quite helpful in predicting extreme events leading to floods. Pq90 is a test of the ability of the system to predict the 90th centile of precipitation. In other words, it is a test of the ability of the system to model the upper tail of the distribution of rainfall. As I said, multi-day rainfall events are important for most (but not all) parts of the UK, so the relevance of px5d is faily obvious, it is those sort of events that will lead to flooding. Pnl90 is not *that* interesting - how many extreme events do we get in one season? Note for pfl90 if you have a very wet season, with rain on most days, then the fraction of rainfall due to extreme events will be lower than in a more normal season, even if the extrem events are the same. Pxcdd is a measure of the ability of the downscaled model to predict the maximum number of consecutive dry days. This is reasonable as the most extreme drought in any season will be the longest one (that is pretty much the definition of a drought). If the model predicts a maximum dry spell of a couple of days, and the observations have 10 or 20 days, then you will get a low value for the pxcdd statistic, which is exactly what you would want to see how good the model is at predicting extreme droughts. There is a good reason why all of the statistics were used in the study; they are all relevant, and it is a mistake to pick and choose as it ignores important context. I should also note that only one of the models was deliberately designed for predicting extreme events on a day-to-day basis, namely MLPR, but none of the indices used are really intended for that sort of resolution (because it isn't important in climatological studies, where it is the longer term statistcs that are of interest). -
CBDunkerson at 22:59 PM on 6 July 2011Over the tipping point
The PIOMAS ice volume model results were recently updated through the end of June and now show an anomaly of about -9800 km^3... breaking the previous record low anomaly set last year by about 600 km^3. If volume loss from now through September followed the long term average, such that the anomaly remained -9800 km^3, that'd result in a September monthly average of just 2500 km^3... well below even last year's (record low) one day minimum of 4400 k^3. To me this suggests that the sharply falling volume trend of the past five years or so has not been 'just an anomaly' or 'caused by export of thick ice'. Rather, it suggests that alot of the volume loss has been due to ice melting in situ due to warmer ocean waters... which if correct would mean that the trend should only continue to accelerate (rather than reversing if it was a statistical anomaly or leveling off if it was due to export of thick ice which no longer exists). This would also suggest that 'the ice stays gone' view is more likely correct than the 'comes and goes' idea from Amstrup's 2010 study in Nature. Interestingly, while the volume is currently about 3300 km^3 lower than at the same point in 2007 the ice extents are nearly identical. This demonstrates how great the disconnect between the two measurements can be. That said, zero volume perforce means zero extent... so as we get closer to zero volume we should start to see extent dropping dramatically. -
Marcus at 22:58 PM on 6 July 2011Glickstein and WUWT's Confusion about Reasoned Skepticism
What temperature dip in the 1970's? The anomaly at the start of the decade was +0.03 degrees, & the decade ended on +0.08 degrees. In between times the temperatures just kind of bobbed up & down-though there was an overall *warming* trend for the decade of +0.06 degrees. Seriously, does Watts *always* just make stuff up as he goes? -
Tor B at 22:55 PM on 6 July 2011Database of peer-reviewed papers: classification problematics
A discussion over at Real Climate.org - see comment #24 - identifies a website with information about debunked anti-AGW publications (agwobserver.wordpress.com). A subsequent post by deconvoluter included “I think it is a mistake to include a minority of papers classified with a little (M) meaning a misunderstood main stream paper. They should be put into a separate list to avoid confusion. Otherwise it won’t be long before you see the authors of such (M) papers claimed by contrarians as supporting their position.” This information may be useful here. I have only superficially checked the referenced website, but it looks credible - like I'm the expert :) -
Eric (skeptic) at 22:26 PM on 6 July 20112010 - 2011: Earth's most extreme weather since 1816?
Dikran, I will try to pay more attention. Obviously I am still learning this area, but I think there is a forest and trees issue here (a region is still just part of the forest). Looking at each statistic from table 1, and ignoring any results: pav and pint are merely precipitation. I am not sure what pq90 means. px5d appears to be a measure of extremes, except that it is only the excessive px5d's that matter. We would need to measure separate statistics for those. pxcdd is a good measure for drought provided we compare the excessive pxcdd from the model to reality. Showing there is a good match for pxcdd for a few days does not necessarily mean there is a good match for pxcdd for 10 or 20 days (or whatever might be considered a drought). Both pf90 and pnl90 appear to be good indications of extremes or a proxy for extremes. -
BBD at 22:25 PM on 6 July 2011A Detailed Look at Renewable Baseload Energy
adelady #160 I'm open to the idea of using the combined electric fleet as backup for renewables intermittency. Some claim this is feasible with smart chargers; others that it is yet more evidence of the fundamental 'perpetual motion machine' fallacy at the heart of all high-renewables projections. In other words, there's never enough energy to go around in the long run and catastrophic capacity shortfalls will occur. In the UK, current planning is for an installed capacity of ca 33GW of mainly offshore wind by ca 2020. The 'battery sceptics' point out that winter anticyclones can effectively stop national wind production for several days. The national electrified fleet might be a workable energetic reservoir for short bursts of backup but it could not cope with this. This is why policy currently leans strongly towards new gas-fired plant as spinning reserve for installed wind capacity once it exceeds 10% of the national energy mix. This is part of the background that informs this short but very revealing piece in the Guardian (see originally #124):One of Britain's leading energy providers warned yesterday that Britain will need substantial fossil fuel generation to back up the renewable energy it needs to meet European Union targets. The UK has to meet a target of 15% of energy from renewables by 2020. E.ON said that it could take 50 gigawatts of renewable electricity generation to meet the EU target. But it would require up to 90% of this amount as backup from coal and gas plants to ensure supply when intermittent renewable supplies were not available. That would push Britain's installed power base from the existing 76 gigawatts to 120 gigawatts. Paul Golby, E.ON UK's chief executive, declined to be drawn on how much the expansion would cost, beyond saying it would be "significant". Industry sources estimate the bill for additional generation could be well in excess of £50bn. E.ON's calculations are part of what the company calls its energy manifesto - designed to draw attention to what Golby described as Britain's "trilemma" - balancing the priorities of carbon, costs and energy security. "We are calling for a new balanced and honest debate about the UK's energy needs, one that truly assesses the consequences in terms of carbon, cost and security of our energy choices. E.ON is investing or has plans to invest in a series of new generation projects including wind, marine, gas and coal and has indicated interest in new nuclear stations. Golby said he wanted to to confront single-issue campaigners. "It is easy to say 'no' to coal, easy to say 'no' to nuclear. I'm quite interested in what they are going to say 'yes' to."
As an end note, that's a significant spinning reserve, and it will emit significant amounts of CO2. -
Dikran Marsupial at 22:03 PM on 6 July 20112010 - 2011: Earth's most extreme weather since 1816?
Eric (skeptic) Pfl90 is not a measure of ability to predict "bona fide" extreme events, it is the fraction of total precipitation due to predicted events over the observed 90th centile. You are just cherry picking the statistic to find one that gives you a reason not to accept the utility of statistical downscaling. Care to explain why the fraction of total rainfall due to events over the observed 90th centile is more informative than the prediction of the 90th centile itself (pq90)? Also for floods on the SE England, five-day precipitation is what causes floods, so why not look at px5d? I have already explained, repeatedly, that return periods can be constructed for regions as well as particular locations. It is also possible to detect trends in return periods using well understood statistical methods (Extreme Value Theory) Thus your second paragraph is (a) wrong and (b) inidcates you are not paying sufficient attention to my posts. -
JMurphy at 21:53 PM on 6 July 2011History Matters: Carbon Emissions in Context
daisym wrote : "Money should never be spent on any CO2 reduction scheme unless and until taxpayers are informed of the quantifiable benefit that would result. Ironically, this isn't happening and will never happen, will it?" With regard to Australia, you could do worse than start here for further information : Carbon Pollution Reduction Scheme -
Mark Harrigan at 21:28 PM on 6 July 2011A Detailed Look at Renewable Baseload Energy
@BBD #166. Thanks for the link BBD - no apology necessary - I understand (believe me!). I'm disappointed :( - but not surprised alas - at the comprehensive torching this link gives to yet another wishful thinking 100% renewables plan. I wish advocates of renewables would try and be more realistic - ultimately they do the case for moving to lower emissions more harm than good by proposing unrealistic feelgood wishful thinking scenariois that can be so comprehensively shown to be impractical. Because then what ends up happening is that any "good" bits get ignored too. I think I stand by my post #161 above - we need to acknowledge that the reliability and cost of renewables remain a significant challenge. Let's focus on how to address that issue rather than pretending it doesn't exist. @adelady #163 - I have to agree with BBD somewhat - if you examine the real cost of Solar PV and Wind they are currently some of the MOST expensive ways to abate CO2 emissions available - do a bit of googling and you will see what I mean. That doesn't mean I reject them as alternatives - only that we need to be realistic about what they can do. Yes improved volume will help but the cost curve reduction is not linear - there are limits. Mind you - there are some other options emerging Paint on Solar But there's a LONG LONG road to commercialisation -
Arkadiusz Semczyszak at 21:23 PM on 6 July 2011The Last Interglacial Part Two - Why was it so warm?
General note: sentient in the previous post “talked” about the MIS 11. It is worth noting that most researchers believe that: “MIS 11 can be considered an analogue for future natural climate changes.” ( Loutre, 2003.) Not Eemian. Rohling et al., 2010.: “MIS-11 is often considered as a potential analogue for future climate development because of relatively similar orbital climate forcing ...” “However [even the here], there is an obvious difference in that the current interglacial (Holocene) spans a single insolation maximum (summer, 65°N), while MIS-11 spanned two (weak) astronomical precessiondriven insolation maxima separated by a minor minimum (due to coincidence of a minimum in 400-ky orbital eccentricity with a maximum in the Earth's axial tilt ...” “In itself, this additional warming from the Sun is too small and too regional to fully explain all the observed warming during the period. It's likely that lowered albedo, increasing CO2 and other carbon feedbacks have amplified this warming from the orbital pacemaker.” Effect of CO2 can explain temperature changes during interglacials, but it is a relationship far more complicated than we think. “It is only when insolation and CO2 act together towards a cooling, i.e. they both decrease together, that the climate enters quickly into glaciation and that the interglacial may be short. Otherwise each forcing alone is not able to drive the system into glaciation and the climate remains in an interglacial state. The same situation applies for the future. However, we already know that CO2 and insolation do not play together. (Loutre, 2003.). By Rohling et al., 2010. “more controversial” is the possibility “variability in the planetary energy balance during Pleistocene glacial cycles was dominated by greenhouse gas and albedo related feedback mechanisms, and that the role of insolation was limited to only triggering the feedback responses (Hansen et al., 2008).” Why "more controversial" - could it be for the reasons referred here ( Schwartz et al., 2010 )? Is worth to draw attention - Rundgren et al., 2005. - on Figure 4 - "raw" data. Together with a possible range of deviations - fluctuations of CO2 are possible (and in a relatively short time) between 160 and 350 ppmv CO2. Changes in the Eemian p.CO2 may thus be significantly underestimated. Only by adopting this latest conclusion, We can answer the question of the Eemian - Why was it so warm? just like Hansen: “... greenhouse gas and albedo related feedback mechanisms ...” -
Eric (skeptic) at 21:22 PM on 6 July 20112010 - 2011: Earth's most extreme weather since 1816?
Dikran, I finally read through the paper in your post 224 It is pretty clear that downscaling does not work well for extremes. There is poor correlation in the bonafide extreme events (e.g. pf90) particularly during the times of year that they matter (spring and summer). In fact almost no correlation between the model downscaling and reality. Furthermore, no matter how many times you insist, the return period statistics are not a valid analysis of increasing risk of extreme events. Sure, they are great for any particular flash-flood or river flood prone area. But to conclude anything about a broader trend in extreme events requires looking at every single possible extreme area statistic. Anything less is a cherry pick. For example, we were briefed on the Toowoomba flash floods above, and a return period statistic may inform the Toowoombians. But what about all the other places that didn't flash flood? Without adding their return period statistics (which may be decreasing) into a whole, there can be no conclusion about any trend. That is why Master's post above comes up short. Sorry to be so blunt, your statistics are strong and I appreciate your criticism of my errors. But in this particular case, I believe you are incorrect. -
Steve Brown at 21:21 PM on 6 July 2011The Last Interglacial Part Two - Why was it so warm?
The global average temperature during the Last Interglacial was likely no higher than 1C. The figure of 5C of warming only applied to high northern latitudes due to the relatively high insolation. This is discussed in part 1 of the series. There is evidence for around 2m of sea-level rise contributed by the melting of the West Antarctic Ice Shelf. It's unlikely that the WAIS would have melted only because of higher insolation at 65N. I totally agree with you that orbital forcing and insolation has been the main driver behind the recent glacial/interglacial cycles, but it's not sound science to exclude all of the feedbacks and processes that would have amplified and distributed the warming around the globe. Reduced albedo, heat uptake by the sea and ocean currents played their part. The orbital forcing behind the last glacial termination peaked with the Holocene Climatic Optimum. For the past few thousand years our orbital configuration has been moving into a cooling phase, yet global temperatures are on the increase. -
hfranzen at 21:09 PM on 6 July 2011OA not OK part 2: Thermodynamic duo
Equation 1 is not sufficient. The correct approach depends upon the model system. Taking a solution of dissolved carbon dioxide, bicarbonate, carbonate, calcium ion and water (containing as always hydrogen ion and hydroxide ion) to be in equilibrium with solid calcium carbonate and gaseous carbon dioxide we can ask what happens when the partial pressure of caron dioxide increases? First the equiulibrium between gaseous and dissolved molecular carbon dioxide is determined by the Henry's Law constant and the concentration of dissolved cabon dioxide increases independent of what happens to the other chemical species. Secondly the product of the carbonate ion and calcium ion concentrations is a constant (the solubility product) and since in this model calcium ion is fixed the concentration of carbonate remains fixed. That leaves the bicarbonate ion concentration to be considered. This concentration will increase and, by electrical neutrality, the hydrogen ion concentration will increase as well (unless it is determined by other reactions not involving carbon dioxide species). The hydroxide concentration will decrease according to the ion dissociation constant for water. When all of these constraints are considered the net result of increasing the carbon dioxide pressure (say according to the Keeling curve): 1. dissolved mo;ecular carbon dioxide concentration increases, 2. dissolved bicarbonate ion concentration increases, 3. pH decreases, 4. carbonate ion concentration remains fixed, 5. calcium carbonate precipitates. This discussion can be modified for the case of "buffering". i.e. nearly fixed hydrogen ion concentration in which case the molecular carbon dioxide concentration increases (Henry's Law), carbonate is fixed by the calcium carbonate solubility product, bicarbonate is fixed by electroneutrality and calcium carbonate precipitates. -
les at 21:08 PM on 6 July 2011Climate's changed before
174 - DougCotton And if anyone says there is no physics basis for planetary orbit driven cycles, and cycles within cycles... just show them this -
Eric (skeptic) at 21:07 PM on 6 July 20112010 - 2011: Earth's most extreme weather since 1816?
#269, Albatross, thanks for that post. A couple of questions though, why are the Great Plains and/or Argentina considered continental tropical areas? Or is that not what you meant? The subtropical parts of the U.S. have the most thunderstorms (Orlando Florida), but not the most severe. Typically the missing ingredient there is cooler and/or drier air aloft. Also my question to Tom in 259 applies, where is global-local connection? You pointed out that more moisture in the low levels is a big contributor to instability. But the increase in moisture is a worldwide average, not necessarily some local area prone to thunderstorms. For example there is currently an anomalous increase in moisture in the U.S. desert SW (a weather pattern). Some storms and dust storms have resulted. But that doesn't mean there is more or less moisture anywhere else in the U.S. The patterns dictate the moisture levels, not the GAT. -
DougCotton at 20:59 PM on 6 July 2011Climate's changed before
There is now statistically significant Fourier transform analysis which detects 60 year cycles in temperature data. There are also obvious other cycles, notably one of about 934 years. These cycles also correlate with planetary orbits as I have explained at earth-climate.com and so we now have proof that gravity from the sun and planets affects Earth's climate. Predictions are for slight cooling till 2028, then warming to 2059 then long-term (934 year) cycle is at maximum and so a long term decline to Little Ice Age conditions about 450 years after that. There is a detailed explanation and reasons on my site. I am happy to answer questions to my email address thereon. -
BBD at 20:58 PM on 6 July 2011A Detailed Look at Renewable Baseload Energy
adelady #163We've already seen how far and how fast the price of solar PV and of wind can come down. Without pushing them further, we'll never know just how cheap they can be.
This is baffling. Please see the article by Helm I quote at #159. For example:Take wind. Britain has one of the most expensive support packages in the developed world. Customers have to buy a proportion of energy from renewable sources, paying the usual price and a premium that the Government guarantees. And that has been doubled for offshore wind. The costs are far greater than conventional technologies, and make even nuclear look cheap. If, as a result, overall emissions were cut on a significant scale, it would at least meet the carbon objective. But because the wind does not blow all the time, there has to be back-up — carbon-emitting coal and gas.
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The Inconvenient Skeptic at 20:40 PM on 6 July 2011The Last Interglacial Part Two - Why was it so warm?
Steve, I am aware of the situation with CO2. You are trying to get off topic. The topic is about the high temperatures of the Eemian and the high 65N insolation. Since you bring up CO2. I will clarify to other readers the situation and why the Eemian is so bad for the theory of global warming. The Eemian was 5C warmer than the Earth currently is with a max CO2 level of 285 ppm and it was really 270-280 for most of the time. But it had a temperature that the theory of global warming associates with almost 2 full doublings of CO2. So lets say the CO2 level for that temperature is 1150 ppm. The Holocene had basically identical pre-industrial CO2 levels, but a temperature that was 5C lower than the Eemian. So the purpose of the above article is to try to explain how the Earth was much, much warmer with CO2 levels that are lower than they are today. The reasonable and simple explanation is that 14% higher solar insolation is the cause. The problem is that the theory of global warming has discounted 65N insolation as being capable of causing the glacial/interglacial cycle. I am glad that you recognize the importance of this Steve. Many would not fully comprehend the significance of the very warm Eemian. I am pretty sure that this website very often uses the CRU temperature as an indication of warming. Even one of the articles that you linked to uses the CRU as 'evidence.' There are other methods, but throwing up a CRU temperature plot is very common and hence would be a standard measure of the Earth's temperature. You still have not discussed the issues I brought up in #4 about the high degree of correlation between insolation and temperature between the Holocene and Eemian. Which I point out might indicate that insolation plays a larger role than you are willing to allowing. -
BBD at 20:40 PM on 6 July 2011A Detailed Look at Renewable Baseload Energy
Mark Harrigan Apologies - not the only bad link I posted yesterday. This is the problem with rattling out comments, late at night, when dog tired. Sometimes I consider giving up on HTML tags and going back to the old ways... It may not have been pretty, but it worked. Anyway, here's the link to the critique(s) of the J&D paper. -
Mark Harrigan at 20:16 PM on 6 July 2011A Detailed Look at Renewable Baseload Energy
@JMurphy #164 - thanks for the link - good to see this is continuing to improve. But I think we must acknowledge there is still a long way to go. It's now got to be able to do 24hrs for 365 days a year - a goal so far not yet achieved anywhere - and 20MW is tiny compared to what we need. And it (ultimately) needs to do so without high subsidy. I think what this demonstrates is validation of my point 3- that CST is the most promising reliable renewable alternative and we should be continuing to invest in it but we should not pretend that is yet able to provide the full solution. It will take many years to scale up to a decent generation size and to provide a 24/7 solution. I'd love to see an example of CST in use as part of a "test" network of wind and possible gas turbine along the lines Diesendorf's plan suggests. I'm told on another post that Hawaii might be an ideal place to do this as it has abundant geothermal, solar and wind capacity. I wonder are there forums where these ideas can be communicated to those in the actual industry and if they read blogs like this? After all just talking amongst "ourselves" is fun but how do we get the message to those that can actually implement these things? -
JMurphy at 19:38 PM on 6 July 2011How would a Solar Grand Minimum affect global warming?
Looks like the UK could be in for some more regular cold Winter spells : UK faces more harsh winters in solar activity dip Among the so-called skeptics, this will obviously result in two responses - 1) New Ice-Age coming; 2) This 'proves' that it's all down to the sun, so AGW doesn't exist. -
ranyl at 19:12 PM on 6 July 2011Over the tipping point
Considering it is the total amount of CO2 that is put in to the atmosphere that counts for global warming outcome and taking the precaution of wanting a 95% chance of keeping to ~2C (that is at most 350ppm by 2100) then isn't zero emissions just the starting point and aren't all the CO2 used to employ any new energy system CO2 that will have to be re-removed from the atmosphere again? To be safe from latest predictions means 350ppm asap and that means a massive carbon sequestration effort or many years of human activity resulting in carbon sequestration or negative carbon emissions. Peak 400ppm, that means 20% reductions in emissions to 2017 and carbon sequestration is necessary to get to 350ppm by 2100 and that is being optimistic about the carbon cycle! This is never going to happen of course as it means the west would have simplify its lifestyle, so what does unsafe CC mean and will it matter how many renewables there are? -
DLB at 18:50 PM on 6 July 2011Great Barrier Reef Part 1: Current Conditions and Human Impacts
Osborne and Sweatman collected lots of cherries from the tree between 1986 and 2009 indicating little change on the reef over the last 24 years. Prior to 1986 there were less cherries left on the ground to pick. Therefore I would be cautious about making any judgement on what the reef health was before 1986. And besides doesn't fruit always taste better in the good old days :) -
Steve Brown at 18:50 PM on 6 July 2011The Last Interglacial Part Two - Why was it so warm?
#4 - Your hypothesis will only work if you can provide a case that falsifies our knowledge of the radiative cross-section of CO2, Methane etc, as well as fundamental physical properties such as the specific heat of water and Planck's Law. If Earth's temperature is dependent on the seasons, why are winters warming faster than summers? Also, the standard measure of the Earth's temperature is not just the atmosphere, but the total heat content anomaly of the oceans and atmosphere. How we know global warming is still happening - Part 1 How we know global warming is still happening - Part 2 The human fingerprint in the seasons -
les at 18:46 PM on 6 July 2011OA not OK part 2: Thermodynamic duo
3 - Rob Painting of course food is going to come into the argument sooner or later. It's what all 'real' scientists know; chemistry is just cooking. "thermodynamics" == oven temperature "equation" == recipe etc.
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