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Fred Staples at 19:43 PM on 21 June 2012Simply Wrong: Jan-Erik Solheim on Hansen 1988
Dana, statististical significance for a trend does not depend on the length of the time scale. It depends on the probability (usually 1 chance in 20) that the observed trend is different from zero. This depends on the signal (if any) to noise ratio. More precisely, on the variance explained by the regression divided by the residual variance. For example, Tamino in his post on diminishing Arctic sea-ice claims significance for 10 year data. My "moderated" posts are all based on original data, scrupulously tested courtesy of Excel. What has this to do with Hansen's predictions/projections? Very little. His projections are the nearest thing we have in Climate Science to an appropriate test in the Popperian sense. He makes predictions based on his theory, which can be tested by events. It is the temperatures that matter, Tom, not the CO2 predictions. Clear your mind, Dana, and look at the Real Climate Chart. The A line temperatures climb steeply after 1990, and head off the page. It was originally the "business as usual" but is now disowned. The B line, which Real Climate claim as the "real" prediction diverges sharply from both the C line and the actuals after 2006. To date the divergence is almost 0.5 degrees C. Actual temperatures are somewhat behind the "C" line, comprehensively contradicting the projections, and the science behind them. Now of course this may change. The "C" and "B" lines must continue to diverge, but the actual temperatures may change direction and move close to the "B" line. If this happens I will change my mind on AGW. If it does not happen, Dana, what will you do? -
MarkR at 18:57 PM on 21 June 2012Adding wind power saves CO2
#11 jimvj: it's worth bearing in mind that Kubiszewski brought together studies from as far back as the '80s and that for newer technologies, the probability of big leaps in EROI is higher. Sherwani et al 2010 considers mostly post-2000 solar PV reports and gets values of energy payback time of 1-3 years in most cases. Since the panels tend to last for decades, it seems realistic that modern solar PV could be somewhere around 10-30 EROI depending on how sunny your area is. Production efficiency, reduction in silicon use and higher efficiency panels needing less materials (double efficiency and you half the panel mass and all the framework etc) probably explain most of the advances since then. Whether there have been similar improvements in CSP I don't know. I have only really read about wind & solar because my country is building lots of wind farms, and my masters was on new electrical contacts for solar cells based on quantum tunnelling. Solar PV is just more fascinating to me! -
scaddenp at 17:59 PM on 21 June 2012Newcomers, Start Here
1-2ppm is not that significant, but 50-100 is and it adds up year by year. Adelady has given you a start but look at The Big Picture. It gives you lots of links and note also the sections on solutions. Your "90% is industry" is a false dichotomy. Who uses the power? A better and highly readable breakdown can be found at Sustainable energy without hot air. The effect of GHG on the radiative properties of the atmosphere has been known since Arrhenius, but the foundational physics can found in Ramanathan and Coakley 1978. Note that the model applies to any rotating planet not just earth. -
Thomas1 at 17:33 PM on 21 June 2012Adding wind power saves CO2
@bmac3130, The number of peer reviewed papers making up the body of evidence of AGW is significant. In order to find some guidance for an obvious novice like yourself I would recommend to use this website's Resources section: http://www.skepticalscience.com/resources.shtml where you will find all the science you will need for a good start on your quest. BTW: Since the industrial revolution we have gone from 280ppm to just about 400ppm now and are on a clear path to DOUBLING the CO2 content of the atmosphere in as little as a century and a half with significant implications to the climate, the ocean acidity and the future of our civilization. -
adelady at 15:58 PM on 21 June 2012Newcomers, Start Here
You could start with Climate Myth Number 30 Some good graphics extracted from a couple of papers and you can follow the research references from both the Intermediate and the Advanced versions. There's also the Intermediate version of Myth 33 Have a look at the whole list of Climate Myths and see if you can spot others that might give leads to the sort of thing that could help you. -
bmac3130 at 15:39 PM on 21 June 2012Newcomers, Start Here
I need help and am not sure where to ask this question, so I will ask the question here and if someone can redirect me it would be appreciated. I am in an online discussion on Amazon about climate change and I recently have received this post. It is the first one I have not known how to answer. Here is the posters question, any advice would be appreciated. "A couple of years ago I surveyed some of the scientific literature on global warming. (The actual scientific literature, not the NYT Science Column or something of that nature.) Now, we know that the earth warms and cools in natural cycles, and the question is "Has human activity been speeding up the warming, and has it done so to such an extent that it will overpower those natural cycles and create a run-away greenhouse effect?" The atmosphere is about 360ppm, that's parts-per-million, carbon dioxide. Due to human activity, this number is increasing by about 1-2 ppm per year. Over 90% of that increase is from industrial processes, and less than 10% is from the day-to-day activities of people, such as driving cars. So we would have to devastate industrial production, including agriculture and electrical generation to make a dent in that 1-2 ppm increase per year. Now, here is my question. Can you cite me some scientific literaure that would support the idea that a 1-2 parts-per-million increase in carbon dioxide would have a significant impact on the thermodynamic properties of the atmosphere? I don't want to hear "but all the scientists who receive large grants from the EPA agree", I want an actual reference to something published in a peer-reviewed journal that would support that statement about the thermodynamic properties of the atmosphere. Will you (or anyone else) please send me that information?" Thoughts? Or peer-reviewed articles which address this topic? -
bmac3130 at 15:38 PM on 21 June 2012Adding wind power saves CO2
I need help and am not sure where to ask this question, so I will ask the question here and if someone can redirect me it would be appreciated. I am in an online discussion on Amazon about climate change and I recently have received this post. It is the first one I have not known how to answer. Here is the posters question, any advice would be appreciated. "A couple of years ago I surveyed some of the scientific literature on global warming. (The actual scientific literature, not the NYT Science Column or something of that nature.) Now, we know that the earth warms and cools in natural cycles, and the question is "Has human activity been speeding up the warming, and has it done so to such an extent that it will overpower those natural cycles and create a run-away greenhouse effect?" The atmosphere is about 360ppm, that's parts-per-million, carbon dioxide. Due to human activity, this number is increasing by about 1-2 ppm per year. Over 90% of that increase is from industrial processes, and less than 10% is from the day-to-day activities of people, such as driving cars. So we would have to devastate industrial production, including agriculture and electrical generation to make a dent in that 1-2 ppm increase per year. Now, here is my question. Can you cite me some scientific literaure that would support the idea that a 1-2 parts-per-million increase in carbon dioxide would have a significant impact on the thermodynamic properties of the atmosphere? I don't want to hear "but all the scientists who receive large grants from the EPA agree", I want an actual reference to something published in a peer-reviewed journal that would support that statement about the thermodynamic properties of the atmosphere. Will you (or anyone else) please send me that information?" Thoughts? Or peer-reviewed articles which address this topic? -
Bob Lacatena at 13:56 PM on 21 June 2012Medieval Warm Period was warmer
Eric,I am not a scientist, so your complicated graphs and explanations mean very little to me.
Then you shouldn't have an opinion on the subject -- or rather, any opinion you hold is by your own admission an entirely uneducated one.Explain to me the definitive proof that shows there is a cause and effect scenario with CO2 and rising temperature.
And how are we to do that, when our "complicated graphs and explanations mean very little to" you? Sort of a Catch-22, isn't it? But everything you need is already here. All of the answers are here, if you're willing to look for them. You should spend less time lecturing, founded on an ignorant opinion, and more time studying. Or you can just go on believing what you'd like to believe, simply because that's in your comfort zone. That's where you're at now, that's where all deniers are (yes, all), and I rather suspect that that is where you're going to stay. Actual facts mean nothing to you. It's much easier to accept the (false) declarations that fall nicely in line with your predetermined beliefs than to work through all of those "complicated graphs and explanations." -
SoundOff at 11:03 AM on 21 June 2012Adding wind power saves CO2
A study questioning the need for back-up generation for wind power Wind power plants have been installed in the United States for long enough that detailed studies have been completed on the impacts and costs of its intermittency. A recent study concluded that, “...the results to date also lay to rest one of the major concerns often expressed about wind power: that a wind plant would need to be backed up with an equal amount of dispatchable generation. It is now clear that, even at moderate wind penetrations [up to 20%], the need for additional generation to compensate for wind variation is substantially less than one-for-one and is often closer to zero. … While wind power does have some costs associated with grid operations, it also has some advantages from the utility’s point of view, including short construction lead times, modularity, no emissions, and higher customer approval” - Utility Wind Interest Group (UWIG) “Wind Power Impacts on Electric-Power-System Operating Costs, Summary and Perspective on Work Done to Date, November 2003” [UWIG is a consortium formed by of a number of US utilities] http://www.scribd.com/doc/77535536/UWIGOpImpFinal11-03 -
DSL at 11:01 AM on 21 June 2012Medieval Warm Period was warmer
Let me briefly add to what scaddenp says: if you haven't read the science, and you claim to be a skeptic, then you shouldn't have any opinion on the science. Actual skeptics use evidence-based reasoning to establish event probabilities. With that having been said, my advice is to back away from the foregone conclusions and actually engage the science. Spend time with it. If you took the time to write on this blog, you must feel somewhat strongly about the issue. If you do feel strongly, make no assumptions, start with the basics, and ask questions. There are plenty of posters here willing to answer questions. Also, as scaddenp indicates, proxies are based on testable physics. Proxy data rules out a great deal of uncertainty. When astrophysicists determine the type of newly discovered extra-solar planets, they do not get clear resolution. They get a rough approximation. Yet even a rough approximation tells them that what they are looking at must fall within a certain range of physical phenomena. They're not looking at a dog or a beer can. Same goes with paleo studies. Because proxy studies are cross-referenced and anchored to known physics, the range of physically possible scenarios for a given point in time gets very slim. -
Tom Curtis at 10:56 AM on 21 June 2012Medieval Warm Period was warmer
Eric from Indiana @126: 1) The article does not say that all, or even nearly all deniers use this argument. It merely says that it is "one of the most cited arguments". Indeed, when I check the list of 173 denier arguments listed by frequency of citation, I find the closely related argument that that global warming is not anthropogenic because "Climate has changed before" is first on the list. The also related argument that "The Hockey stick is brocken" is 16th, and this argument is 30th. That certainly makes it one of the most frequently cited denier arguments. So, the claim in the article is accurate, and it is you who are being unfair "almost to the point of dishonesty" by putting words into others mouths. That, however, is a side issue for me. What I wonder is, do you argue against these claims when you see your fellow deniers make them? If you think the argument absurd, but sit in silence while fellow deniers make these claims, you show that truth is not what you are interested in. 2) No scientist has set out to expunge the MWP from the record books. Nor have scientists made conclusions based on very limited and dubious data. As an example, consider the following graph:
The important line for this discussion is the greenline, which is a temperature reconstruction excluding all tree ring data, and all data from proxies that have been considered dubious by deniers. It still shows a MWP that is cooler than current temperatures. The myth (and it is a myth) that you have been fed saying the temperature reconstructions are based on just one tree in the Yamal series are false. (The easiest clue that it was false was that it was made on a denier site.)
3) If you want proof that increasing CO2 increases temperature, read this post. Having done so, please point out the flaw in the logic. If there is no flaw, than increasing CO2 increases temperature.
Note, posting on Skeptical Science is a privilege based on your compliance with the comments policy. You have already violated several comments policy, and continuing to do so may well result in portions, or the entirety of future posts being deleted.
Finally, I have referred to you as a "denier". You may object to being classified by a stereotyped and negative description. You may even find it offensive. However, you yourself are using stereotyped negative descriptions ("alarmist") in your post, so I figure, "Sauce for the goose is sauce for the gander".
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scaddenp at 10:40 AM on 21 June 2012Medieval Warm Period was warmer
Whoops - forgot the link. Start with the Big picture -
scaddenp at 10:38 AM on 21 June 2012Medieval Warm Period was warmer
Eric, I'm a little unsure on where to start here. You are saying that your "your complicated graphs and explanations mean very little to me" so how much are you prepared discuss this really? Oddly, you readily swallow "that used only 12 trees in your tree ring data, including one freak tree to bend the graph favorably in your direction." How skeptical were you of that claim? What about proxy reconstruction that dont include trees? (and yet give same picture) As has already be pointed out, MWP is a/ different from today in that it occurred in different places at different times, b/ something that climate models reproduce from known forcings. This is not proof, but you cannot have proof in science, only in mathematics. What we do have is observation that are consistent with the predictions of climate theory. Furthermore, note that if it was hotter globally (little evidence to support this) than today, then this is evidence for high sensitivity and you should be more worried. "Explain to me the definitive proof that shows there is a cause and effect scenario with CO2 and rising temperature." Warning - this involves understanding some science but I doubt you would be visiting this site unless you had some interest in what the truth was. Start with -
michael sweet at 10:21 AM on 21 June 2012Adding wind power saves CO2
This newspaper article describes severe coal shortages in India. I have seen articles saying private companies in India are installing solar PV because it is the cheapest source of power during blackouts (which are usually during the day). New sources of coal for the life of a power station are difficult to obtain even in the US. Perhaps we will get lucky and coal will run low before we fry from AGW. Wind looks good now. The problem with wind is long transmission wires to bring it to many major cities. In the USA we have large resources for both solar and wind. I would be interested in seeing a study comparable to the OP that looks at Spain. Spain has installed a lot of wind recently. In February Spain generated 22% of its electricity from wind. They have reached peak output of over 50% of electricity from wind at times. The linked newspaper article claims they saved a lot of money (power is apparently cheap in Spain) and didn't emit as much CO2. -
Composer99 at 10:19 AM on 21 June 2012Medieval Warm Period was warmer
Eric from Indiana: Suffice it to say, it doesn't strike me as properly skeptical behaviour to make claims of scientific incompetence or even malfeasance with regards to studies of the medieval climate anomaly without substantiation. -
Eric from Indiana at 09:37 AM on 21 June 2012Medieval Warm Period was warmer
"One of the most often cited arguments of those skeptical of global warming is that the Medieval Warm Period (800-1200 AD) was as warm as or warmer than today. Using this as proof to say that we cannot be causing current warming is a faulty notion based upon rhetoric rather than science." This is not fair. Almost to the point of dishonesty. I am a skeptic by nature. No, the Warm Period does not PROVE that the warming is not caused by man, but at the same time all the alarmists models do not prove that it is. You are putting words into half our mouths by claiming that all of us skeptics use this as evidence that definitively proves our point. That is far from the truth. The alarmists do themselves a great disservice to their cause by ridiculing their opponent for not jumping onto their bandwagon. You just make it more difficult for us to agree with you when you do this. You all were the ones that excluded the Warm Period to get more drastic results. You were the ones that used only 12 trees in your tree ring data, including one freak tree to bend the graph favorably in your direction. Why is it that the Medieval Warm Period is excluded as being an anomaly, yet this freak tree is considered good scientific evidence? Don't treat us skeptics all the same. We have different ideas and mindsets. I am not a scientist, so your complicated graphs and explanations mean very little to me. Because even with my limited knowledge of astrophysics, I know that all it takes is 1 little miscalculation to throw everything out of whack. Accurate temp records have only been kept for the last 100 years. So when you point to ice core records that shows "accurate" records over the last million years, forgive me if I don't jump to a conclusion from them. Explain to me the definitive proof that shows there is a cause and effect scenario with CO2 and rising temperature. Because I could just as easily do the same thing as this author did and point out the flaws in the logic of showing the rise in CO2 leading the rise in temperature during the 80's, and saying that is proof of cause and effect. Of course CO2 is going to continue to rise even if the temperature drops if the temperature had been relatively high for the previous 80 years. Yes the warming may have started around the same time as the Industrial Revolution, but this is also when accurate temperature recordings were beginning to be kept, as well as it was the same point in time when we began moving out of a 500 year cold period, which had been the coldest period in the last 10,000 or so years. Like I said, I am not a scientist. But I do understand the scientific method, and what I see with these models, and the definitive conclusions being made from them, goes against everything I been taught about the scientific method. -
Tom Curtis at 08:56 AM on 21 June 2012Simply Wrong: Jan-Erik Solheim on Hansen 1988
thepoodlebites @16, here are Hansen's projections for various GHG concentrations in 2011, and the current (2011) annual concentrations for those gases: Year: 2011 Actual Scen A Scen B Scen C CO2 (ppmv) 390.5 393.74 391 367.81 NO2 (ppbv) 322.5 334.1 329.94 313.93 CH4 (ppbv) 1810.5 2617.77 2234.52 1915.84 CFC11 (pptv) 240 1220.89 553.99 275.49 CFC12 (pptv) 533 2096.56 960.92 523.59 You will notice that for all values,the closest value is either Scen B or Scen C, and that only three values (CO2, NO2 and CFC12) exceed scenario C, with none exceeding Scenario A. There is no basis for being skeptical about actual emissions being closer to B other than a determination to ignore the evidence. -
Paul D at 08:23 AM on 21 June 2012Adding wind power saves CO2
Re comment 1 (cynicus). I think Bart Ummels was a post grad student when he wrote that report?? It did get a lot of publicity. Has he continued research in wind energy since then? -
Bob Lacatena at 08:09 AM on 21 June 2012Simply Wrong: Jan-Erik Solheim on Hansen 1988
It is just amazing to me that "skeptics" can't understand something as utterly simple as this, and that "skeptic-wannabees" latch so readily onto arguments like this one, without the slightest trace of skepticism (because if they had, they'd immediately see how silly this position is). Why is it that we never, ever see the skeptic sheep step up and say "wait a minute, that's not right." I mean, with all of the ridiculous arguments that are out there, how come not once do the skeptics go "wait, this is embarrassing." Everything from this constant attack on 1988 Hansen, to attacks on 1999 Mann, to Postma's nonsense... Really? Skeptics can't take any of these laughable arguments to task? Not one? -
Bob Lacatena at 07:36 AM on 21 June 2012Arctic sea ice takes a first nosedive
I have looked at this incessantly (really, I should get help) for years now. I have a list of bookmarks a mile long. I glance at but ignore the charts. I instead look at a number of different sites that show concentration and thickness. I also tend to try to watch the animations, to get more of a temporal/spacial sense of the change. And this year is NOT your father's Arctic ice melt. The starting point was very, very different, not in extent but in thickness, and the progression has been very different. I will not be at all surprised if the bottom completely drops out this year, but if it doesn't, it's only because it's laying the groundwork for the bottom to drop out next year. Two things matter (IMO): 1) The ice is now so thin and fragmented that wind and currents are making a major contribution to the process. This wasn't possible 20 years ago, because the ice was too thick and interconnected until too late in the season. 2) What really matters is each year's "annual progress" on the thick, mostly permanent ice off the north coasts of Greenland, Ellesmere Island and the Queen Elizabeth Islands. That ice looks to me like the foundation on which everything else rests. The end will come quickly when that fragments enough to drift out and be carried physically, by wind and current, in fragments, to places where it can more easily melt away. This year looks like it could be "that year." -
vrooomie at 06:53 AM on 21 June 2012Adding wind power saves CO2
Apologies to the moderator: I'm STILL not gettin' the hang of hotlinking. I *am* a geologist, after all...;) -
vrooomie at 06:47 AM on 21 June 2012Adding wind power saves CO2
Some of the naysayers of wind energy remind me--sadly--of the first cartoon on this website. http://info.ussolarinstitute.com/blog/bid/59854/Top-10-Solar-Energy-Cartoons I live almost within sight of one of Colorado's largest wind farms, Cedar Creek, and I think they are a *wonderful* resource that is steadily coming into its own, as an viable energy source. It's not really a matter of *if* we utilize the technology, it's that we *must* utilize it, where feasible.Moderator Response: [Sph] Hot linked for dumb, techno-incompetent geologist. -
Neven at 06:42 AM on 21 June 2012Arctic sea ice takes a first nosedive
I forgot to say: anyone who wants to compare current ice cover to that of previous years, can have a look at the concentration maps on the Arctic Sea Ice Graphs website. It's a quick way to see how weird or unusual something really is, or just which regions are melting out faster or slower compared to previous years. -
Rob Honeycutt at 06:29 AM on 21 June 2012Adding wind power saves CO2
Larry... Exactly. That's about what I would expect to see. It takes a lot of money to build these things and the ROI is so long, and the cost of renewables is going down while the cost of extracting coal is going up... I just imagine the people who usually finance these things are saying, "I'm not seeing how this can work long term." And with those sums of money people are very, very risk adverse in their investing. That would be really good news if we are now seeing the last coal plant built. That plant will be with us for the next 30-40 years but at least it's the right direction. -
LarryM at 05:57 AM on 21 June 2012Adding wind power saves CO2
Rob @ #8: The Union of Concerned Scientists has a good analysis explaining why new coal plants are no longer a prudent investment. It's called A Risky Proposition (click on "Executive Summary"). With the new EPA regulations, it's very possible that the last new coal plant has already been built in the U.S. (but many will still be retrofitted with pollution controls and be with us for decades). -
jimvj at 05:37 AM on 21 June 2012Adding wind power saves CO2
The other real eye-popper is how bad solar thermal is. If so, why are so many companies opting to put huge solar thermal farms in the US southwest? Is it all tax incentive based? Solar thermal, I think, is more efficient at converting solar radiation into electricity than solar PV (at least outside of a lab environment). Obviously the embedded energy costs of the steam turbine plant, the mirrors, the land prep, etc must be really high. Is there a breakout of these costs available online? -
KR at 05:36 AM on 21 June 2012Simply Wrong: Jan-Erik Solheim on Hansen 1988
As an interesting side note, while Hansen 1988 has rather too high a sensitivity, and somewhat overestimates the actual warming trend based on actual emissions, Hansen et al 1981 underestimated those trends by ~30%, and still beat "no-change" or "linear trend" predictions. By no means were either the 1981 or 1988 models perfect - which, if you actually read the papers, Hansen states repeatedly. Aerosols are an ongoing issue, as is the exact level of cloud feedback. But making comparisons to the 1988 Scenario A (as Solheim did) is a complete strawman fallacy, and as per the lessons from predictions series documents, actual science does a much better job of predicting outcomes than the 'skeptic' models or claims. -
Fred Staples at 05:03 AM on 21 June 2012Simply Wrong: Jan-Erik Solheim on Hansen 1988
(-Snip-)Moderator Response:[DB] For many months now you have been bombing threads with comments focused on timeframes too short to be of any significance. In short, you continually focus on the "noise", not the "signal". And this, despite repeated counseling to the contrary. This constitutes "sloganeering" and is in violation of the comments policy.
Continuance of this pattern of posting behavior will result in an immediate cessation of posting privileges.
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adamski5807 at 04:17 AM on 21 June 20122012 SkS Weekly Digest #24
what do people think about this?? Billions and billions of trees to solve the problem?? http://members5.boardhost.com/medialens/msg/1340210498.html -
MarkR at 02:54 AM on 21 June 2012Adding wind power saves CO2
#8 Rob: I don't think we can make it that cut-and-dried. Coal doesn't need to include backup, and it's cheaper to fit into the current grid system. Wind has to pay for these extra costs and I suspect that in many cases this means it's still more expensive than new coal, although my focus here is purely on the technical aspects rather than the economic ones. And of course, coal gets an enormous subsidy, paid by the rest of us, for being able to dump its pollution into our air for free. If this externality was closed by charging for pollution rights like econ 101 says it should be, then the market would work it out pretty quickly. -
MarkR at 02:51 AM on 21 June 2012Adding wind power saves CO2
#7 Composer99: there seem to be a number of reasons for the spread including different LCA methods, changes in turbine size and how well they are sited. However, wind does seem to have improved with time. For studies from the 1980s, only 1 in 8 reports an EROI > 10. For the 2000s this has risen to 41 in 48. -
Rob Honeycutt at 02:49 AM on 21 June 2012Adding wind power saves CO2
I just don't see how or why anyone is putting money into new coal plants these days. It seems to me that by the time they come on line they are not going to be cost competitive with other resources. MA @ #4... I think the fact that the situation with anti-wind lobby and the wind industry is indicative of the state of build out. Coal (which I assume is the main source of the anti-wind lobby) is established. A large portion of their infrastructure is in place and even fully paid for, so they are fully in the black and can put money toward lobbying efforts. The wind industry is the upstart kid on the block and all their money is getting invested in building and installing new units. That means they're not going to have anything close to similar resources to use for lobbying efforts and PR. I expect that will likely change in the not-too-distant future. -
dana1981 at 01:43 AM on 21 June 2012Simply Wrong: Jan-Erik Solheim on Hansen 1988
poodle, Hansen's scenarios are projections, not predictions. A projection is "if x happens, then y will happen as a result." Since emissions didn't follow either Scenario A or B exactly, we wouldn't expect the Scenario A or B temp projections to be perfect. So to say Scenario A and B ran too hot - that's exactly what we would expect to happen. We would also expect the temperature rise to be about 16% below Scenario B if Hansen's model were perfect, given actual emissions. It wasn't, because as tonydunc and myself and others have noted, the model sensitivity was 4.2°C for doubled CO2 which is probably too high. Accounting for the difference, it tells us that fast feedback equilibrium sensitivity is around 3°C. -
Composer99 at 01:41 AM on 21 June 2012Adding wind power saves CO2
Based on the EROI plus uncertainties shown, even if future studies show a significantly lower EROI for wind it's looking good compared to coal. -
John Chapman at 01:11 AM on 21 June 2012Arctic sea ice takes a first nosedive
The irony about the north passage opening up, is that it is attracting suggestions that there could be good prospects for oil. Maybe they can also mine coal on some of those frozen lands when the ice is gone?! -
tonydunc at 01:07 AM on 21 June 2012Simply Wrong: Jan-Erik Solheim on Hansen 1988
Poodle, the problem might be that you are not noting that everyone, Hansen included, accepts that Hansen's sensitivity of 4.2°C for doubling of CO2 was wrong at least for the short term. This is something that I have repeatedly pointed out to deniers but it is almost never acknowledged. SO yes his predictions are too warm for that reason. Also there are numerous factors such as Asian aerosols, persistence of La Niña, etc, that could be dampening the effects of CO2 on the short term as well. That could also "make" his "predictions" wrong" but not his science. -
MarkR at 00:57 AM on 21 June 2012Adding wind power saves CO2
#3 john mfrilett Johnny Vector is right. The Energy Return on Investment counts the energy in the fuel as 'free'. This is a way of getting an idea of the useful energy returned to the economy based on inputs. A random figure I didn't want to bulk out the text with: ORNL says you get ~6150 kWh of electricity per ton of coal. A 3.6 MW wind turbine weighs hundreds of tons and over 20 years produces ~30,000 tons of coal worth of electricity. Suddenly the EROI figures sound a bit more believable. -
Johnny Vector at 00:04 AM on 21 June 2012Adding wind power saves CO2
john @3: This calculation does not include the energy in the fuel. This is strictly looking at the energy coming out of the plant divided by the total energy it takes to build and operate the plant over its lifetime. That includes the energy to make the materials out of which the plant is built, to build it, to maintain it, to mine/pump and transport the fuel, and to shut the plant down safely when it's no longer useful. So, coal takes a lot of energy to mine and transport, which reduces the lifecycle efficiency. Nuclear plants, OTOH, get a lot of power out of a smaller amount of mining (I think), but their decommissioning takes a lot of energy. Wind turbines probably cost more per kW to build and install than coal plants, but they require almost no energy to operate and decommission. So they win in this measure. The reason this is important is that you could imagine wind turbines being so large and complex that the energy needed to build them would be more than the energy you would ultimately get from them. Ethanol from corn, for example, is on the hairy edge of being energy neutral in this way. Growing the corn and processing it takes roughly (i.e. within a factor of 2) the same amount of energy as you get by burning the ethanol. -
MA Rodger at 23:46 PM on 20 June 2012Adding wind power saves CO2
cynicus The anti-wind lobby do a good job of disinformation and sadly the wind industry seem singularly inept (here in UK) at presenting its case. In 'your recent online discussion', I'd say I smell a rat. Getting information "first-hand from the plant operators" sounds like rubbish unless it is a public source, one which "the other" appears to be keeping private. Note also to crazy logic of saying "gas is currently so expensive" so the coal plants are used as the 'spinning reserve' resulting in "very high balancing costs." A few years back, the UK power industry was trying to get subsidies for new gas power-plants by pleading that high wind capacity would result in all their new gas power-plants running intermittently as the 'spinning reserve'. .e.g. here. Their latest wheeze to get gas catagorised as 'low carbon' for the next 30 years appears to be more successful. e.g.here. And of course, within such a political ding-dong any amount of crazy logic is par for the course. However, such talk, whatever the source, doesn't mean it describes something that is actually happening. -
john mfrilett at 23:45 PM on 20 June 2012Adding wind power saves CO2
Some one please explain to me how a coal plant can produce more energy that it consumes? The coal generating station would have to operate at greater than 100% efficiency to produce numbers on the graph. I thought coal plants needed about 3 units of energy (sorry I have no reference for this) for every unit they produced? To my mind wind is a far better deal than this article suggest. -
Riccardo at 23:38 PM on 20 June 2012Seagrasses Can Store as Much Carbon as Forests
In general, I'd expect that calcareous species will be/are affected most by a pH reduction, not sea-grass which might even benefit from added CO2. Though, I should have said I don't know, I'm sure a google search will do better. -
thepoodlebites at 22:19 PM on 20 June 2012Simply Wrong: Jan-Erik Solheim on Hansen 1988
18. Belay my last, make that Hansen's 1988 (not 1998) temperature predictions (both A and B) were too warm. Sorry about that, I try to be careful. Those responsible for sacking the people who have just been sacked, have been sacked. -
thepoodlebites at 22:13 PM on 20 June 2012Simply Wrong: Jan-Erik Solheim on Hansen 1988
Bill, you're accusing me of persnickety strawmen but I'm just trying to understand the woodfortrees.org plot. Thanks Dana1981. A 60-month average definitely changes how one interprets the observations. I've included the 13-month UAH plot and we can clearly see the 1998 and 2010 El Nino events. I agree that Solheim's 1998 peak seems exaggerated but this doesn’t change the argument that Hansen’s 1998 temperature predictions (both A and B) were too warm. I’m still skeptical about actual emissions being closer to B but will study more about that. I guess you can accuse me of being a nit-pick about the empirical evidence but it represents the best ground truth that we have so far. -
funglestrumpet at 22:03 PM on 20 June 2012Seagrasses Can Store as Much Carbon as Forests
What effect does ocean acidification have on seagrass? -
cynicus at 19:56 PM on 20 June 2012Adding wind power saves CO2
Question about: "The inefficiency from turning power stations on and off takes a bite out of the savings that wind power brings, but since the most polluting power stations get turned off first the savings are still big." I recently had an online discussion where I claimed this, since gasturbines (e.g. STEG powerplants) are much more suitable and efficient in loadfollowing then coal-plants, the wind-intermittency would be balanced by the gasturbines. The other claimed that gas (in Western-Europe) is currently so expensive that coal-plants are used to do the balancing, causing massive CO2 releases from wind-balancing and very high balancing costs (i.e. 30 Euro/MWh which is 10x higher then most studies show in even high wind grid penetration levels). I have a hard time to believe this but he claims to have this information first-hand from the plant operators. Can anyone from the business comment on this? -
cynicus at 19:09 PM on 20 June 2012Adding wind power saves CO2
Another research paper (2009 thesis) by Bart Ummels from TU Delft in cooporation with grid operator TenneT that focusses on the situation in The Netherlands shows roughly the same results as Valentino et al. 2012: high levels of windpower can be integrated into the grid without large changes to the grid and provide significant CO2 emission reductions. As a sidenote: De Groot and LePair appear stereotypes for the retired physicist who venture into an area they know too little about but with an axe to grind. They are notorious in The Netherlands for their anti-wind news articles. They indeed show their true colors when they falsely argue that wind forecasts aren't used and that all backup is provided by the least efficient power stations possible (Open-Cyle Gas Turbines). Bart Ummels has also commented on the claims by LePair&co., unfortunately in Dutch, but his critique agrees with the critique provided here by MarkR. -
Neven at 18:07 PM on 20 June 2012Arctic sea ice takes a first nosedive
Now that you know what to look for, shoyemore, check out today's ECMWF weather forecast, click N-Hem. and then 144h onwards on the 500 hPa, SLP row. You see those huge high-pressure systems over the Canadian Archipelago? If those come about, the ice in the Northwest Passage is going to break up so hard. -
shoyemore at 17:43 PM on 20 June 2012Arctic sea ice takes a first nosedive
Neven & Sphaerica, Thanks guys. I am now fully armed for the melt season. -
scaddenp at 17:27 PM on 20 June 2012New Research Lowers Past Estimates of Sea-Level Rise
I cant find a really suitable solution thread, but I have continued here. -
scaddenp at 17:26 PM on 20 June 2012Three new studies illustrate significant risks and complications with geoengineering climate
Continuing a discussion that started here. Eric. There are multiple issues here: 1/ Progress might be inevitable, but you cannot expect progress that violates physical laws and you cannot assume that just because something can be done then it is economic to do so. Just looking at the hurricane or El Nino data and you see that minimum energy costs are huge. Why would you assume that it is economic to spend this energy rather reduce emissions? 2/ A chaotic system obeys physical laws. Not all states are possible. Air that is cold with respect to surrounding will settle creating the high just as warm air rises. You might move the cyclone belt around (with enormous energy inputs) within some bounds but its general position is determined by the radiative heating profile of the planet. 3/ The increasing southward trend is warming Antarctica's fringes, bringing rain to melt the ice and increasing the issues of sealevel rise, not decreasing it. Look at the GRACE map of mass loss/accumulation and ice loss trend.
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