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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. -
skywatcher at 18:43 PM on 6 July 20112010 - 2011: Earth's most extreme weather since 1816?
Albatross, can I just thank you for the superb post on thunderstorms at #269! Having just watched a 'Spanish Plume' breakdown in the UK and a day when a convective cap was not broken despite high dew points and lots of CAPE, I've learned a lot in the last 10 minutes. -
les at 18:15 PM on 6 July 20112010 - 2011: Earth's most extreme weather since 1816?
267 - Norman"Precipitation patterns for Mid-Atlanctic region. Look at the graphs. They show cycles. "
You have spent quote a lot of time, as 270 Dikran points out, setting very particular requirements for what is science and then make the strong statement "They show cycles" based just on the eye-ball-o-matic?!?! May I suggest this post by Tamino for how to scientifically analyse an AMO data set for cycles. That's doing science; compiling 10 or 20 links isn't.Moderator Response: [Dikran Marsupial] Link fixed -
Mark Harrigan at 18:01 PM on 6 July 2011Over the tipping point
@Jerry #4 Perhaps then you need to lobby the relevant pollies in Hawaii who want a highly visible electoral platform to get in touch with Mark Diesendorf and see if they will adopt such a program? I've no idea what the generation cost base is in Hawaii but I can see that it would, on the face of it, be a natural place as you say for geo-thermal, solar and wind. It would also seem to be highly vulnerable to a break in oil supply? Is the power utility there private or government? Who knows - Hawaii could be a great showcase for a renewables experiment? :) -
JMurphy at 17:53 PM on 6 July 2011A Detailed Look at Renewable Baseload Energy
Mark Harrigan, your plan is not bad at all. With regard to concentrated solar, though, things are moving on : Gemasolar solar power plant reaches 24 hours of uninterrupted production -
adelady at 17:42 PM on 6 July 2011A Detailed Look at Renewable Baseload Energy
Mark "I can't see ANY way forward except putting a whole lot of effort into ANYTHING that looks promising. We should rule nothing out if it can contribute. ... Okay - now tear me to pieces!" Nuh, no pieces. My view is much the same about trying absolutely everything. We'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. And the same thing goes for other technologies. We might think they're expensive now, but we haven't tried hard enough for long enough to see which of them will (and which of them won't) follow the same cost trajectory. As for coal being around for a long time ...? That's another reason for pushing renewable technologies as hard and fast as possible as soon as possible. If the climate goes truly and horribly pear-shaped without much warning*, there'll be an outcry demanding either clean coal or no coal - which will lead to ghastly impacts when some areas lose most or all of their power supply. If people demand that coal be left in the ground (think asbestos, there's still plenty of that around, it's just too dangerous to use) everyone will be much better off if we already have a range of fairly cheap alternatives on the go. *not much warning? from the pov of view of those who weren't paying attention. Think WWII. -
adelady at 17:25 PM on 6 July 2011Over the tipping point
Paul D I agree that zero emissions will always be impossible. However I don't think that zero net emissions is out of reach. It's perfectly sensible for people to complain, at the moment, that carbon offsets with tree planting schemes and the like are little more than greenwashing. However, if emissions were only the truly unavoidable ones - say liquid fuels for (some) air travel and other specialty applications, it would be pretty easy to work out the size of the block of olivine (or similar rock) you need to buy for crushing to ensure near instant absorption by weathering of the equivalent amount of airborne CO2. So a little bit of appropriate geoengineering - speeding up absorption of CO2 to exactly match the accelerated release of CO2 - would be manageable. Viola! Zero net emissions. -
Jerry at 17:00 PM on 6 July 2011Over the tipping point
Mark, I live in a place that would be perfect for such a test--Hawaii county. We have a relatively small population (185,000) with ample geothermal, solar and wind resources. Yet the vast majority of our electricity is produced from oil. It drives me crazy that this island is not self-sufficient in electrical production. The power utility thinks they are being radical by trying to produce 30% from non oil sources by 2020. Jerry -
Dikran Marsupial at 16:58 PM on 6 July 20112010 - 2011: Earth's most extreme weather since 1816?
Norman The reason that I introduced the double pendulum into the discussion was to correct your deeply misguided view of what is science and what is not. The lack of certainty or the ability to make accurate predictions does not mean something is not good science, and the double pendulum demonstrates that. Like the weather it is chaotic and hence unpredictable, even though we can write down equations that provide a perfect characterisation of its behaviour. You had been brought to the point where you could not reasonably discuss the double pendulum any further without contradicting yourself. The fact that you tried to deflect the discussion away from the double pendulum suggests to me that you know that, are not really interested in counter arguments to your position and are just trolling. This confirms my earlier prediction that further progress in discussing the science with you was unlikely. -
Paul D at 16:47 PM on 6 July 2011Over the tipping point
Zero emissions will always be impossible. Wind turbines are not zero carbon systems, they are very low carbon systems, as are most renewables and sustainable systems. Production, maintenance and decommissioning of the systems will have a small carbon footprint. We can ultimately only do our best and reduce greenhouse gas emissions to the lowest possible. -
owl905 at 16:32 PM on 6 July 2011History Matters: Carbon Emissions in Context
Quite the opposite of being a 'moral' piece, the assignment of responsibility is a core issue of this pollution problem. President Bush derailed the American response with his false escape argument about America's unfair share. The Chinese grabbed the angle, and used it at the Bangkok Conference in 2004 to claim the old western imperialist nations were responsible for 90% of all the pollution to date. Proper share is a stumbling block that derails the mitigation approach. The result isn't someone else throwing a bucket of water in the tub - it's everyone throwing a bucket of water in the tub. -
Albatross at 15:52 PM on 6 July 20112010 - 2011: Earth's most extreme weather since 1816?
Tom, Norman, EricS,and others. Gee, this thread going to get as long as the "Its not the sun" at this rate ;) I think that Dr. Masters is of the opinion that the preponderance of severe events in 2010 is consistent with the increasing trend, and a system that is increasing in sensible and especially latent energy (i.e., moisture). This post is going to focus on thunderstorms and severe thunderstorms in particular, and how they might change in a warmer and more moist planet. I have written about this at length elsewhere at SkS, so I encourage people to read the posts made here, and here. In short, the research to date suggests that severe thunderstorms will increase in intensity as the planet warms and low-level moisture increases. Some seem to think that there is a "jump" or disconnect between the observations that low-level moisture has increased (and will continue to do so) and the occurrence of severe thunderstorms. I'll show that the physics and theory support that link. First, that lightning map that Tom showed us at #258. Tom, I have to agree with Norman on this one. Lightning frequency or occurrence is not typically a good proxy for thunderstorm severity. The strongest storms are typically observed over mid-latitude land areas, not over the tropics. Thunderstorms, are of course, most frequently observed over those areas. The reason for that are simple. For a thunderstorm to form one requires the realization of three criteria (all of them, not just one or two): low-level moisture (by that we typically mean in the near surface or boundary-layer, although some storms are what we call 'elevated'), instability and a trigger to lift the air to its level of free convection (examples of triggers include surface heating, fronts, outflow boundaries, drylines etc.). These criteria are, not surprisingly, most often met over the continental tropical areas. In fact, research has shown that the the most intense thunderstorms on the planet are likely found over Argentina and the southern Great Plains of the USA. I can attest to this as someone I work with told me about how a Lear jet flying into one of the storms stalled on account of the incredibly strong updraft-- we are talking updraft speeds of 50 m/s. Now for severe weather one either requires really strong buoyancy (difference in temperature between the storm's updraft and the surrounding ambient air) and/or vertical wind shear. The wind shear has a two-fold affect on updraft-- it can organize the upraft and separate the updraft and downdraft, also it can induce non-hydrostatic pressure perturbations in the storm which can cause the updraft to accelerate. Thermodynamically, one can increase the amount of buoyancy by increasing the low-level moisture and/or by increasing the lapse rate of the environmental air. The biggest bang for you buck though in this regard is to increase the low level moisture. Now this can all be explained using theory. The moist-static energy (MSE) in the low levels is given by: MSE = gz +CpT +qL (1), where g is the gravitational constant, z the height, Cp the heat capacity of air, T the air temperature, q the specific humidity or water vapour mixing ratio, and L is the Latent heat of vapourization. Because L is such a huge term, the moisture really dominates the MSE of the air. Now a metric that is used to quantify the amount of buoyant energy in the atmosphere is the convective available potential energy (CAPE). CAPE is simply the vertical integration of the positive temperature difference between a parcel rising along the moist adiabat and the corresponding ambient air temperature between cloud base and the equilibrium level. It can be shown that the maximum updraft in a storm is given by: Wmax = (2*CAPE)^0.5 (2), Now this is a theoretical value and it ignores the decrease in the updraft strength because of entrainment of cooler/drier air into the updraft and the reduction in of updraft strength by water loading of the precipitation and other factors. Empirical observations have found that observed Wmax values are closer to 0.6-0.7 of the theoretical value. The important part. Crook (1996) showed that by manipulating equation (1)increasing the low moisture by 1 g/kg increases the CAPE by 2.5 the amount as a 1 C warming of the low-level air would. So changes in near surface specific humidity of 10% or so of typical background values can have a huge impact on the buoyancy available to a storm, and in turn the maximum updraft strength-- as found by the papers I cited in one of my posts above. Increasing low-level moisture also has another important factor, it increases the liquid water content of the updraft. For hail to develop one, in basic terms, requires strong updrafts, long residence time in the updraft (typically a longer-lived updraft), and relatively high liquid water content. As the aforementioned discussion has shown increasing the low-level moisture increases the buoyancy (i.e., updraft strength), and the liquid water content of the updraft. For a hail embryo to grow into a large stone it needs to reside in a strong (moist) updraft for a long period of time, so an organized updraft helps, and that is oftentimes (but not always as shown below) where the vertical wind shear comes into the picture. So the short of it is that increasing the low-level moisture is likely to increase the chances for more intense/severe thunderstorms, and perhaps larger hail too. Work by Botzen et al. (2010) predicts that: "Extrapolations of the historical relations between hailstorm damage and weather indicators under climate change scenarios project a considerable increase in future hailstorm damage." But what about the vertical wind shear that is supposed to decrease (note that they are not predicting it will go away) over the mid latitudes as the planet warms? Well, as the research has shown, the impacts of less wind shear are offset by the increase in CAPE. Additionally, strong vertical wind shear is not a requirement for extremely large hail. Consider this recent example from Kansas, where they had > 5 cm diameter hail on 2 July 2011. The sounding below shows that the low levels were very moist (dewpoints > 20 C), the CAPE was also near 3400 J/kg, see here. The only problem was the stable air between 900 and 800 mb (aka a capping lid)-- that had to be overcome to tap into the huge convective available energy. Note the relatively weak winds in the lowest 6 km (0-6 km AGL wind shear is often used to quantify the bulk wind shear), suggesting relatively weak vertical wind shear. To cut a long story short the capping lid was broken and this was the result:
[Source]
Hail with a diameter of near 7 cm. The huge CAPE on this day was clearly critical in permitting giant hail to be produced in an environment with relatively-low wind shear, and this case is by no means an outlier.
And a closing, but important, note on wind shear. Research has shown (see for example the work by Markett and Allen (2003)) that the precipitation efficiency of thunderstorms increases as vertical wind shear decreases. So in the future we could see a higher incidence of torrential downpours from storms having higher precipitation efficiencies arising from any decrease in wind shear. Hardly a plus.
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Mark Harrigan at 15:31 PM on 6 July 2011A Detailed Look at Renewable Baseload Energy
Oops - that's dialogue of the deaf!! under my definition of "The Problem". DOH!! -
Mark Harrigan at 15:28 PM on 6 July 2011A Detailed Look at Renewable Baseload Energy
@tom #145 and all the above Tom with due respect I do not think comments about courtesy or otherwise are helpful. I did not say anything discourteous (or if I did I apologise) My post at 142,was challenging some of your logic about mine deaths (which I think you acknowledge) and also taking issue with your characterisation of my comments about Nuclear being CO2 free in operation by which I thought was clear meant when it is in operation providing power (which is an indisputable fact) But let me pick up on some of your further points (especially at #150) which I think are very pertinent and see if I can take them further? @BDD this is I think relevant for your points too as I agree the post at #159 cannot be ignored (I can't get your link at #154 to work on the critique). This appears to be the problem that Britain is grappling with (and I suspect Australia is about to have to contend with) and I think is a real example of everyone pushing a particular barrow. I don't have the answers but maybe I can add some thoughts? We can all argue till the cows come home about the exact Nuclear CO2 life cycle emissions and safety. I think (please correct me if you disagree) that we can all agree that what matters is the comparison? If we compare nuclear with coal it wins hands down on both safety and emissions - no matter how you calculate them. So in my opinion nuclear displacing coal is a "win" If we compare nuclear with renewables the situation is somewhat more vexed. (for the purposes of this post I'll focus only on those renewables such as Solar PV, Concentrated Solar Thermal (CST) and Wind all of which have almost no geographic limitations in application) On Safety I don't want to argue the toss about someone else's data showing nuclear to be more or less safe than renewables or more or less CO2 emissions - it probably comes down to whose figures you accept and, let's face it, both the nuclear industry and the renewables industry have axes to grind and this will bias their data and views accordingly. My own personal opinion is that it would be hard to argue conclusively that renewables are inherently less safe than nuclear. I stand by my comments on risk and hazard above for nuclear at #135 and #142. The risk is tiny but the hazard is huge So score a win for renewables on safety but not a slam dunk? On Emissions So what's the situation with CO2 emissions of nuclear versus renewables? Tom makes I think the relevant points in the last paragraph of his post #145 When they are producing power it's probably a scoreless draw? On the life cycle issue they should be about equal on plant fabrication and nuclear ought to lose a peg or two on the fuel cycle issue. So score a (minor) victory to renewables on that one? But with renewables the issue comes down to what today is still an incontrovertible fact. A renewables plant by itself simply cannot meet reliable 24/7 baseload demand. The only available solution to this involves backing up renewables with CO2 producing alternatives. A problem nuclear does NOT have score a decisive victory for nuclear on that issue The Problem If you broadly accept my characterisation above then this describes pretty well for me at least what I meant in my earlier posts about the world being full of lesser evil choices. So how to pick the lesser evil? This is where I think the real problem lies that we need to solve and until we do there will continue to be a debate between nuclear and renewables advocates that too often descends into a dialogue of the death. The article that spawned this thread makes a case for getting round this real renewables problem by (my characterisation) a widely geographically dispersed generation "utility" linked together in a smart grid supported by rapid response gas/biofuel turbines to handle the "unreliability" issues of any given renewables plant. In principle this sounds feasible but the reality is we don't know as it has not been tested. The other way around this problem would be for renewables to improve their reliability. The only serious contender for this is surely CST. But it isn't viable today. But now here is the problem and where I think the wishful thinking on the part of renewables advocates lets them down. It is simply not feasible to move to 100% renewables today without considerable technical, commercial and social risk. And I don't want to ignore the real problem of nuclear hazard So how do we get from here to there? (there being the wonderful CO2 free emissions environment of future power emissions) and within our limited budgets? A Part Answer? There's no magic answer but I think we must do several things. First because I think there is no certain answer we should not bet on a single approach. So nuclear by itself is NOT the answer (and in any event won't fly politically) but neither are renewables. Whilst I don't accept BDD's limitation of 30% as being forever the fact is right now renewable are a whole lot less than that and if we don't want the lights to go out won't be higher anytime soon. I suggest the following (though not in any order of importance) 1) Invest in a realistic test of Mr Diesendorf's plan - the idea has merit - to what degree can we make it work? That implies some work on the grid which is wise 2) Replace aging goal with latest technology Gas (it's more expensive but it works, has substantially lower emissions than today and can be part of 1 ) 3) Pour more investment into CST reliability. 4) Because none of the above can happen quickly, don't take nuclear off the table anywhere but require any new nuclear proposals to be subjected to rigorous overview and assessment. 5) because of all the above Coal is going to be around, whether we like it or not, for a LONG time globally (just look at china) we need to continue to develop sequestration or other clean coal alternatives Summary Most of all I wish we'd stop arguing about alternatives as if it's one or the other. I can't see ANY way forward except putting a whole lot of effort into ANYTHING that looks promising. We should rule nothing out if it can contribute. We can use Carbon pricing (tax) to price higher emissions out of the market over time and we can use incentives (direct investment, accelerated depreciation, tax discounts) to try and get alternatives off the ground. (Direct investment for early stage, accelerated depreciation for capital requirements on large scale implementations of lower CO2 plans and tax discounts for more mature low CO2 operations). Okay - now tear me to pieces! :) -
Bern at 15:26 PM on 6 July 2011Over the tipping point
I delved into the comments over at The Drum... and now my head hurts! Comments about how arctic ice doesn't affect solar heating during the arctic winter; equating "models have uncertainty" with "models are completely wrong"; and the best one of all, quoting WUWT as an authoritative source of scientific information! That one also linked a graphic showing total global sea ice area, claiming it doesn't show any decrease. I tried to post a comment that the graphic in fact clearly shows a decline of at least 2 million km2 over just the last 30 years, which is an area as large as NSW, Victoria, and Sth Australia put together, but that hasn't made it through the ABC moderators yet. -
dana1981 at 15:25 PM on 6 July 2011Glickstein and WUWT's Confusion about Reasoned Skepticism
Don't worry Chris, all that warming is still just due to magical natural cycles.
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