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Comments 90101 to 90150:

90101. Peter Bellin at 02:37 AM on 6 April 2011
       Learning from the Climate Hearing
       Paul Krugman had an excellent editorial on the sham Congressional hearings have become. http://www.nytimes.com/2011/04/04/opinion/04krugman.html
90102. Fred Staples at 02:30 AM on 6 April 2011
       2nd law of thermodynamics contradicts greenhouse theory
       What others (explanations of AGW) someone may ask. I collected the following explanations from one thread at RC: Ekholm in his 1901 paper: . . . radiation from the earth into space does not go directly from the ground, but on the average from a layer of the atmosphere having a considerable height above sea-level. . . The greater is the absorbing power of the air for heat rays emitted from the ground, the higher will that layer be. But the higher the layer, the lower is its temperature relatively to the ground; and as the radiation from the layer into space is the less the lower its temperature is, it follows that the ground will be hotter the higher the radiating layer is. Chris Colose This is one of the problems I have with the simple layer model as it is introduced in some textbooks, such as Dennis Hartmann’s or David Archer’s “Understanding the Forecast.” This is where you simply add up the influence from successive blackbody “layers” with a final result of something that usually ends up looking like T_s=T_eff*(N+1)^0.25, where N is the number of layers, and T_s and T_eff are the surface and effective temperatures, respectively. Archer discusses some of the incompleteness of this model in his class lectures (lack of convection, layers are not fully transparent in the shortwave nor fully opaque in the longwave) but I think the whole presentation misses the point completely Barton Paul Levenson Your CO2 absorbs an infrared photon, one of its electrons jumps a level, and it either radiates another photon of the same level, or more likely, crashes into a nearby nitrogen or oxygen molecule and transfers some of the new stuff as kinetic energy. Temperature is a measure of kinetic energy at the molecular level; the faster the molecules jiggle, the hotter the object. Thus the atmosphere warms up. Those collisions transfer energy *back* to the CO2, which radiates by the (wavelength-specific) Stefan-Boltzmann law. Some of the energy goes back down to the surface and heats it above what it would be from sunlight alone. Eli Rabett The short answer to the question of where the energy comes to warm the surface is from energy that left the surface but was turned around by backradiation. Without the greenhouse gases it would just keep going And RayPierre “The way the greenhouse effect really works is that adding CO2 reduces the infrared out the top of the atmosphere, which means the planet receives more solar energy than it is getting rid of as infrared out the top. The only way to bring the system back into balance is for the whole troposphere to warm up. It is the corresponding warming of the low level air that drags the surface temperature along with it” Settled Science?
       Moderator Response: [Dikran Marsupial] Some of those explanations are completely consistent with the "Top of the atmosphere" explanation, particularly that of Ekholm, Rabbet and RayPierre. Colose seems to be merely arguing a point on the details and Levinson is discussing part (anl only a part) of the same mechansim.
90103. muoncounter at 02:28 AM on 6 April 2011
       There is no consensus
       Neo#297: "My point was that the church had the consensus" Consensus of what? Consensus of 'this is the way we say it is'; that;s not scientific argument. So that's a nonsensical start. "AGW has become its own religion. It has to be taken on faith." And now a descent into the ridiculous; this is called science, not faith. It is far more of an act of faith to blindly accept that AGW is not happening. Go to WUWT and proclaim otherwise; you will be quickly persecuted. Tackle any anti-AGW argument with scientific argument; you will find 'No, its not' is all that's left. So stop the bogus, self-defeating arguments. You'll have to do lots better here.
90104. Albatross at 02:25 AM on 6 April 2011
       There is no consensus
       Neo @297, "Because I dare read information contrary to the “consensus” I am a heretic" No, your posts here do bear remarkable resemblance and have the hallmarks of a troll, and probably violate the house rules Might I suggest you please go back to WUWT or wherever else you have been obtaining your misinformation and anti-science snippets. And for the record, this is my first and last post to you.
90105. Fred Staples at 02:23 AM on 6 April 2011
       2nd law of thermodynamics contradicts greenhouse theory
       Gosh . I dislike quoting the luminaries directly, but here are quotes from RC and Open Mind: RayPierre Humbert In a nutshell, then, here is how the greenhouse effect works: From the requirement of energy balance, the absorbed solar radiation determines the effective blackbody radiating temperature Trad. This is not the surface temperature; it is instead the temperature encountered at some pressure level in the atmosphere prad, which characterizes the infrared opacity of the atmosphere, specifically the typical altitude from which infrared photons escape to space. The pressure prad is determined by the greenhouse gas concentration of the atmosphere. The surface temperature is determined by starting at the fixed temperature Trad and extrapolating from prad to the surface pressure ps using the atmosphere’s lapse rate, which is approximately governed by the appropriate adiabat. Since temperature decreases with altitude over much of the depth of a typical atmosphere, the surface temperature so obtained is typically greater than Trad, as illustrated in Figure 3.6. Increasing the concentration of a greenhouse gas decreases prad, and therefore increases the surface temperature because temperature is extrapolated from Trad over a greater pressure range. It is very important to recognize that greenhouse warming relies on the decrease of atmospheric temperature with height, which is generally due to the adiabatic profile established by convection. The greenhouse effect works by allowing a planet to radiate at a temperature colder than the surface, but for this to be possible, there must be some cold air aloft for the greenhouse gas to work with. Tamino “If a parcel of air rises, because of the reduced pressure the parcel will expand. It generally takes much longer for a parcel of air to absorb/emit heat from/to its surroundings than to expand/contract, so during its expansion it will, for all practical purposes, exchange no heat with its surroundings; in other words, the expansion of the parcel of air will be adiabatic” For a text book derivation I quoted page 45 of Elementary Climate Physics by FWTaylor (mentioned in the far distant introduction). The lapse rate is a function of gravity and specific heat and is about 6K per kilometre of altitude. If we cannot accept this very basic Physics, we are entitled to ask who are the denialists in this debate. Anyone can see the compression/decompression effect for themselves by inflating a bicycle tyre or releasing the pressure in a gas cylinder. The question of the transparent atmosphere is frequently raised. An atmosphere which was totally transparent to radiant energy, unable to absorb or emit, would still have a lapse rate. Its low pressure at altitude would be colder than its high pressure at the surface. However, it would be a very strange gas indeed. Unlike everything else in nature with a temperature, it would not radiate. It would allow the surface to be in radiative equilibrium at 255 K, and would not affect this temperature by thermal insulation, convection, conduction, or evaporation. Not worth debating, I think. As I said in a previous response "The explanation you offer, Very Tall Guy, is the only plausible explanation of the AGW effect. It is the preferred explanation of the founding fathers over at RC, and you can find it in the Rabbet rebuttal of the G and T paper, (immediately following their absurd multi-layer, back-radiation explanation). It begins with the lapse rate, a function of gravity and specific heat, which has nothing to do with radiative effects. Without this lapse rate there would be no possibility of AGW. The argument is that increasing CO2 in the cold, dry, upper atmosphere, impedes outgoing radiation, and moves the effective radiation point to higher (and therefore) colder temperatures. Outgoing radiation is reduced, incoming radiation remains the same, and the whole atmosphere and surface warms up to restore the balance. As your drawing demonstrates, the lapse rate moves to the right". The dominance of water vapour in the AGW stakes (often quoted by the sceptics)is not a factor because, at this altitude, the air is dry. This is a plausible explanation, unlike all the others. It implies that AGW is a top of the atmosphere effect, and that the temperature increase (right shift of the lapse rate) should be greater at altitude than at the surface. More subtly, it suggests that increasing the concentration of CO2 in the stratosphere will absorb and emit energy more efficiently, and thus cool the stratosphere.
       Moderator Response: [muoncounter] Please do not quote long passages from other blogs; we are fully capable of following links to them. And to avoid the possibility that you might be quoting selectively or out of context, you must provide those links anyway.
90106. dana1981 at 02:18 AM on 6 April 2011
       Learning from the Climate Hearing
       Albatross #5 - I believe John has had some discussions with the Union of Concerned Scientists regarding distributing our politician quotes/myths from the hearing (and 'what the science says') to some congressmen. Hopefully they can make it happen.
90107. Neo Anderson at 02:17 AM on 6 April 2011
       There is no consensus
       #287: My point was that the church had the consensus and they vigorously defended it to the detriment of science. Further, perhaps my analogy was a little too subtle, but to some, AGW has become its own religion. It has to be taken on faith. Also #287, you can watch videos on YouTube of AGW scientists such as Mann, Hansen, etc… getting in arguments over exactly what the consensus is. #289: It is documented that weather recording sites were moved from the open country to city parking lots. There was apparently much frustration at the lack of temperature increase in much of the southwestern United States. I guess it has now proven that parking lots and rooftops are much warmer than the countryside. Years of potential valuable data was destroyed. A few of these sites can be viewed at norcalblogs. Also #289, I agree that the “objections” were looked at some point in the past. However since they were contra-AGW, they were dismissed. After awhile there is so much contra-evidence that I don’t feel it can be ignored. Scientists who consider all of the evidence are labeled as deniers and ridiculed. Would you please list just one study that is accepted by the consensus that contradicts AGW. #290: This is a typical example of what I am talking about. Because I dare read information contrary to the “consensus” I am a heretic. I am not informed. I am now ‘informed.’ #292: Same thing as #290. Once again, the fact I read both sides of the issue implies that I have read the wrong stuff. If I read only the pro-AGW literature, then I would be informed. (And thanks for listing just a few of the sites I have spent much time reading and studying.)
       Moderator Response: Please note this site's Comment Policy before posting. Comments are expected to stick to the science and remain on topic. This ensures that the debate remains civil and scientific. The topic here is the scientific consensus regarding AGW. If you wish to discuss the reliability of the temperature record, you can do so in the Temp record is unreliable thread. Future comments in violation of the policy will be edited or deleted.
90108. Albatross at 02:11 AM on 6 April 2011
       Learning from the Climate Hearing
       Dana, I bet. Good that the misinformation, distortion and obfuscation of the Republicans and their witnesses is going on the public record Do you know if anyone has plans to send the copies of this series to senators in the USA?
90109. dana1981 at 02:06 AM on 6 April 2011
       Learning from the Climate Hearing
       Albatross - thanks, many more "punches" to come. Watching the hearing made us fighting mad!
90110. dana1981 at 02:02 AM on 6 April 2011
       Learning from the Climate Hearing
       clonmac - several of the Democrats made the point that we need to continue funding climate science research to address the "ignorance" the Republicans were harping on. Hopefully they were listening. You're right, you really can't argue that we don't know enough to act, and simultaneously defund research on the subject.
90111. Albatross at 02:01 AM on 6 April 2011
       Learning from the Climate Hearing
       Good gracious, a one-two "punch" from SkepticalScience! An intriguing, insightful, but depressing read.....
90112. Albatross at 01:56 AM on 6 April 2011
       Arctic Ice March 2011
       Wow, the contrarians and those in denial about AGW sure are in a tizzy now that the Arctic ice loss is ramping up. Really, contrarians are just resorting to trolling this thread now to fabricate debate, what is sad is how transparent it is; observant readers here will not fall for that ploy. They are simply not "seeing" the loss of multi-year ice (green shading) because they do not wish to let their mind comprehend it. There is clearly a mental block there. Arctic sea ice volume is decreasing, and at an accelerating rate (see PIOMAS data and NSIDC data). The issue of feedbacks feedbacks is also discussed here at the NSIDC site in a report titled "Weather and feedbacks lead to third-lowest extent". "Since the "pronounced minimum" in 2007 the extents in 2008, 2009, and 2010 were all higher... yet multi-year ice and total ice volume continued to decline" From NSIDC: "At the end of the summer 2010, under 15% of the ice remaining the Arctic was more than two years old, compared to 50 to 60% during the 1980s. There is virtually none of the oldest (at least five years old) ice remaining in the Arctic (less than 60,000 square kilometers [23,000 square miles] compared to 2 million square kilometers [722,000 square miles] during the 1980s)." So CBDunkerson and the NSIDC are in agreement. No surprises there, b/c unlike the contrarians, CB seems to actually consult the appropriate authorities and literature, and does not simply eyeball graphs to arrive at his/her preconceived notion. Sphaerica sums it up nicely @113, as does this figure from NSIDC:
90113. Alexandre at 01:46 AM on 6 April 2011
       Climate myths at the U.S. House Hearing on climate change
       michael sweet at 01:17 AM on 6 April, 2011 The SkS list has a lonely Democrat there: Collin Peterson
90114. clonmac at 01:41 AM on 6 April 2011
       Learning from the Climate Hearing
       This is one of the most discouraging reads. It disgusts any time I hear about politics muddling up climate science. Republicans can only ignore science for so long before it comes back and bites them. Unfortunately, in the case of climate science, we don't have the luxury of time. It just irks me when I hear Republicans say that more research needs to be done on climate change, yet then they turn around and attempt to defund NASA's climate research programs. That's the epitome of denial.
90115. Dikran Marsupial at 01:33 AM on 6 April 2011
       Arctic Ice March 2011
       Giles@111 Why would you expect to see evidence of positive feedback from just one week's observations. While you clearly know there is natural variability, you obviously don't understand that the shorter the period of observation, the more the results are dominated by natural variability (i.e. weather). That is pretty much weather-v-climate 101! If you want to see evidence of positive feedback, then the accelleration in ice loss over the last couple of decades is far better evidence (the thermal inertia of the oceans means that any immediate effect is going to be miniscule - but that doesn't mean that it stays miniscule if continued for a decade or two, rather than just for one whole week).
90116. Albatross at 01:20 AM on 6 April 2011
       Climate myths at the U.S. House Hearing on climate change
       Great effort John and Dana, very well done. Not to mention less than a week following the testimony-- so great turnaround. I hope that this gets a lot of coverage in the media (assuming that they have woken up from their prolonged nap on failing to expose the inaneness and logical fallacies of the "skeptics'), as it should, because it demonstrates the incredibly sad state of affairs in American politics, and that of 'skeptics" and deniers of AGW in general. Either these Republican politicians and their witnesses (likes of Christy) are incredibly ignorant, or they are knowingly deceiving and distorting and even lying at times. People speaking at these hearing should be required to testify under oath that they will tell the truth, the whole truth and nothing but the truth. As a scientist, I long ago gave up paying any attention to Curry. Here is hoping that this story gets legs....people need to know that the Republicans and their cohorts (e.g., Christy) are deceiving, distorting and being anti-science and obstructionist in their behaviour.
90117. michael sweet at 01:17 AM on 6 April 2011
       Climate myths at the U.S. House Hearing on climate change
       Alexandre: "Nearly". Who was not Republican? It is interesting that Watts is now criticizing Muller for doing the same thing watts is doing with his site survey. whjat would Watts have said if the conclusion was different? You would think that Muller would learn from his past mistakes and stop his unsupported comments. Where will they publish their study: "We have done this study over and found out that Hansen was right all along".
90118. jmsglr at 00:49 AM on 6 April 2011
       The Climate Show Episode 10: David Suzuki and the sun
       The link is broken.
90119. Bob Lacatena at 00:44 AM on 6 April 2011
       Arctic Ice March 2011
       111, Gilles,

       ...there is no obvious self-sustained acceleration through positive feedbacks

       And who ever said there was? You're creating a strawmen. obvious? self-sustained? acceleration? through positive feedbacks? Why the need to qualify things into such a bizarrely worded and so heavily qualified box? Why does it need to be obvious? Why does it need to be self-sustained (as opposed to caused by, and then contributing to, GHG induced global warming in a global, not regional, feedback loop)? Why does it need to be accelerating (it is, as clearly evidenced by the 30 year trend, but that's not the point)? Why is it only relevant if it is occurring through direct positive feedbacks (as opposed to CO₂ alone, or through indirect feedbacks, that contribute to the overall rise in global temperature)? If you want to say "there is no obvious self-sustained acceleration through positive feedbacks" go right ahead. But taken individually: Summer Arctic ice extent is obviously decreasing. The trend is accelerating. The cause is CO₂ induced global warming. One effect is an increased positive feedback due to decreased albedo over a large area of ocean during a time of year when insolation in that region is very high. So while your carefully constructed and obfuscating statement may be arguable, the component facts are not. When considered intelligently, rather than in a confused and confusing jumble of misrepresentations, the situation is nothing short of alarming.
90120. Tom Curtis at 00:32 AM on 6 April 2011
       Arctic Ice March 2011
       Ken Lambert @103, thank you. I did in fact make an error in my spreadsheet, and thanks to your prompting I have corrected it. The correct values are: Additional energy absorbed due to melted sea ice in the Northern Summer: 6.2*10^21 Joules Tonnes of Ice melted if all that energy was used to melt ice: 1.8 * 10^13 tonnes Area of 3 meters thick ice melted if all the energy was used to melt ice: 6.7 x 10^6 km^2 Percentage of surviving ice cap melted if it was all applied to melt ice: 90% I believe these figures are more than sufficiently large enough to rebut any "its to small an effect to matter" style arguments. I have been through the figures again, and I do not think I have made any further errors. Indeed, I am making conservative assumptions in ignoring additional energy captured in the spring and autumn; and by neglecting the large portion of the ice that lies below 74 degrees latitude and which therefore would have a higher insolation (which would more than counterbalance the ice melt above that latitude). I have also treated the additional melt back over the 30 years as being 2 degrees latitude, whereas from the chart it is closer to 3. So, all in all, I am out by a factor of approx 2. I have searched through the only paper of Trenberth's published in August 2009 that I know of. It does not contain, that I can find, any figure for additional energy absorbed due to ice melt. Nor, indeed, would such a figure be relevant to the paper, so far as I can tell. It does mention that, annually, approximately 1*10^13 Joules of energy is consumed melting ice. That means the additional energy gained through melting of sea ice compared to the ice extents 30 years ago is approx 600 million times more than is needed to drive additional melting of ice that occurs each year (on average). So, until you can produce an exact quote from Trenberth, including a citation that quotes the title of the paper, I am going to conclude that the "discreprancy" is simply a consequence of your mistaking different figures as representing the same estimate. Specifically, I will assume that you have mistaken an estimate of total additional energy absorbed (what I calculated) for the net additional amount of energy absorbed, ie, the total additional amount absorbed minus the total additional increase in outgoing energy. Finally, as a reality check, according to Trenberth and Fasullo, "Changes in the flow of energy through the Earth's climate systems", 3.85 * 10^24 Joules flows through the Earth's system each year. The additional net energy absorbed due to water vapour and ice albedo feebacks is 3*10^22 joules. The net energy absorbed each year amounts to 1.5*10^22 joules. (Figures from the introduction to the article. Figures originally give as Petawatts, but converted to Joules by multiplying by (60*60*24*365.25). These figures are very hard to reconcile with your claims about Trenberth's results.
90121. Alexandre at 00:19 AM on 6 April 2011
       Climate myths at the U.S. House Hearing on climate change
       Nearly an all-republican list...
90122. Gilles at 00:13 AM on 6 April 2011
       Arctic Ice March 2011
       105, 108 : again I wasn't arguing that the decrease has stopped. I was arguing that I couldn't see any evidence for a significative positive feedback. I know there are natural variability, weather, atmospheric patterns, call them like you want. I just say there is no obvious self-sustained acceleration through positive feedbacks.
90123. Gilles at 00:09 AM on 6 April 2011
       Arctic Ice March 2011
       #101Since the "pronounced minimum" in 2007 the extents in 2008, 2009, and 2010 were all higher... yet multi-year ice and total ice volume continued to decline." well that's not what i'm seeing here the 2007 minimum is logically followed by a minimum in 1-year old ice the year after, and by a minimum of 2-years old ice two years after ...there is no sign of non-linear feedback increasing the slope after these minima.
90124. JMurphy at 23:49 PM on 5 April 2011
       It's cooling
       We seem to have a new so-called skeptic argument : "Don't trust any of those elitist scientists and their modern, new-fangled, hoity-toity instruments and measurements - nature knows the truth and we will trust them to reveal their secret knowledge to those who we want to believe can understand what they are trying to say to us. Until anyone can actually speak to nature and interpret it, we can never be disproved and can believe what our internet gurus and blog scientists tell us !"
90125. otter17 at 23:45 PM on 5 April 2011
       Climate myths at the U.S. House Hearing on climate change
       Wow, John Christy looks to be the first place contrarian at the hearings, most quotes featured on Skeptical Science. If I were a climate scientist who worked on the IPCC or the hockey stick, I would be steaming mad at all the sweeping accusations of misconduct and bias in a US congressional hearing. Why can't these folks directly address the scientists that they disagree with or show evidence of an error via a peer reviewed paper? This type of mudslinging isn't done to identify errors in other scientific disciplines, right? In my field of engineering, the peer review process for some IEEE societies gets a bit heated, but I have never heard of anybody being anything but civil.
90126. JMurphy at 23:33 PM on 5 April 2011
       10 key climate indicators all point to the same finding: global warming is unmistakable
       RickyPockett, you would do well to read the following, which answer all the beliefs you seem to hold - starting with the main link from the article you are posting in (which you seem not to have read) : State of the Climate Newcomers Start Here The Big Picture Evidence for global warming Is there a Scientific Consensus on Global Warming ? Atmospheric CO2: Principal Control Knob Governing Earth’s Temperature CO2 – An Insignificant Trace Gas? The economic impacts of carbon pricing
90127. Bob Lacatena at 23:27 PM on 5 April 2011
       Arctic Ice March 2011
       104, Ken,

       Is it more or less than the Arctic?

       This is the crux of your problem. The question is not whether the energy absorbed is large relative to anything other than what has always happened in the past thousands of years. The point is not whether it is large compared to the tropics, or the south pole, or to a light bulb. The point is that it's happening when it has never happened before... and it is going to happen every year! Every year the earth is going to absorb that much more energy that it never absorbed before, and which should be reflected back into space. And contrary to your efforts to treat the amount as inconsequential, it is not. Your argument is equivalent to claiming that the earth will never get as hot as the surface of the sun, so therefore global warming is negligible and not a problem.
90128. adelady at 23:23 PM on 5 April 2011
       Arctic Ice March 2011
       Gilles, I really hadn't grasped the source of your confusions on this. Just as warming does not mean that each succesive year must be warmer than all previous years, so declining ice does not mean that every year must be a new record minimaum. In fact, the ice is showing something we don't see in the global temperature. If you look back at that 'tale of the tape' graph above, you'll notice that several years and for decades before that the year to year variation in anomalies was quite small. However, the last 5 years show much greater year to year variation in anomalies. I suspect this reflects the much steeper decline in multi-year ice - which has tended to maintain the ice around it. Now that it's nearly gone, the year by year ice freeze and melt is showing much more variation.
90129. Bob Lacatena at 23:21 PM on 5 April 2011
       Arctic Ice March 2011
       93, Gilles,

       How would I explain that ice is currently growing again despite the relatively low maximum?

       If you watch the animation, you can see the ice "growing" at an alarming rate, on the order of hundreds of miles in days. I don't believe it's remotely possible that ice in the open ocean is freezing that fast. So what else could be happening? The ice further north is melting, breaking up, and drifting south. So the increase in ice extent (i.e. the area of ocean over which floating ice is detected) is expanding because of the ice melting further north, and drifting south. Ice extent at this time of year is virtually meaningless because of this effect. From the original post above:

       Sea ice extent in February and March tends to be quite variable, because ice near the edge is thin and often quite dispersed. The thin ice is highly sensitive to weather, moving or melting quickly in response to changing winds and temperatures, and it often oscillates near the maximum extent for several days or weeks, as it has done this year. Source: NSIDC report March 23, 2011

90130. Bob Lacatena at 23:14 PM on 5 April 2011
       Arctic Ice March 2011
       104, Ken, Of course it does, because no matter what anyone says, you conflate and distort and throw out reems of words, and declare yourself correct. This works for you, because you are in denial. But it convinces no one.
90131. Dikran Marsupial at 22:31 PM on 5 April 2011
       Arctic Ice March 2011
       Giles@93 How would I explain that ice is currently growing again despite the relatively low maximum? Easy, it is called "weather", and small peaks and troughs in sea ice extent are evident in the plots for every year. How do you explain that the extent has stabilized after the 2007 minimum? Again, weather. "This is not supposed to happen in case of a positive feedback, things should only worsen!" Incorrect, positive feedbak only biases sea ice extent downwards, if it was strong enough that the extent was forced to decrease monotonically the ice cap would have been too unstable to exist in the first place. The comment about stabilisation after 2007 suggests a lack of appreciation of the statistical issues. You only need to look at the data to see that the annual variability in sea ice extent is rather larger than the trend, so any "stabilisation" is likely to be statistically insignificant. In statistics there is also a thing called "regression to the mean", which implies that if you get a record high or low in some quantity, it is inlikely there will be another record low/high soon after (because record lows are caused by a conjunction of influences all acting together and such coincidences are generally rare). Your post is making the same mistake as "no global warming since 1998", i.e. drawing conclusions from a period too short to get statistical significance and cherry picking a start date that happens to be a record extremum.
90132. CBDunkerson at 22:28 PM on 5 April 2011
       Upcoming book: Climate Change Denial by Haydn Washington and John Cook
       Ann, to extend your conceit even further there are two other 'possible' alternatives... either live with the disease while treating the symptoms (i.e. allow global warming to happen and attempt to mitigate the impacts) or hope that a theoretical new cure may eventually become viable (i.e. geo-engineering). That said, mitigation would cost vastly more/be vastly less effective than prevention and any geo-engineering effort would be going in blind with a radical and untested new field of science that might well do more harm than good. Also, h pierce... remove the use of fossil fuels to generate electricity and we could continue all other current fossil fuel uses (including automobiles) without raising atmospheric CO2 levels any further. Of course, we'd then run out of gasoline in short order... so we might as well convert the cars over too. Which leaves us lots of coal, petroleum, and natural gas for all the other things (such as those you note) that they are critical for... which we would no longer be able to do if we burned them all up for energy generation. Ergo, it seems fairly clear that even without global warming we have reached the point where we >must< convert away from using fossil fuels for nearly all forms of energy generation.
90133. johnd at 22:13 PM on 5 April 2011
       10 key climate indicators all point to the same finding: global warming is unmistakable
       RickyPockett at 15:47 PM, I think the effects of deforestation is something that is yet to be fully understood and thus has not been properly quantified and accounted for in the global climate system. Deforestation is not of recent advent, but began in earnest with the large scale building of wooden boats. Obviously this began the rapid reduction of timbered areas in coastal areas and along waterways. Knowledge that has been accumulated shows that the difference between forested and non-forested land on how far precipitation penetrates inland can be many thousands of kilometres, with the forested areas acting as a "pump" driving moisture inland that otherwise would quickly runoff back into the oceans, but this idea has only really began to be seriously considered over the past 5 years. This effect on the water recycling system plays into the atmospheric circulation, affecting wind circulation and cloud distribution patterns and thus the areas of differential heating.
90134. Ken Lambert at 22:12 PM on 5 April 2011
       Arctic Ice March 2011
       Sphaerica #90 "I stopped responding because you're in clear denial and therefore not open minded in any way, so there is no point to continuing this. Briefly, the simple answer to your geometry question is that we're not talking only about the exact spot of the north pole, but rather the entire area affected by ice. I did err in the 66˚ -- the angle of incidence in the area in question is probably between 30˚ and 38˚, but that still gives open water an albedo that is substantially more than "negligible", so your argument is still moot." I am not in enough denial to get my numbers wrong though, am I Sphaerica?? The angle of incidence is not a probability - it is a geometric fact determined by the tilt of the Earth's axis relative to the orbital plane about the sun. As the Arctic circle rotates once every 24 hours in the northern summer - half of the surface bounded by it will see the sun at an incidence angle of between 23.4 degrees and 0 degrees for 12 hours (night), and half will see it at between 23.4 and 46.8 degrees for 12 hours (day). The average angle will be that at the pole - 23.4 degrees. The open water albedo will be that for an incidence angle of 23.4 degrees - which is a lot higher than at 66 degrees (the equator) which is as low as 2% over calm water. My point remains - this all applies to the Arctic - 4.4% of the Earth's surface at an incidence angle of 23.4 degrees in the middle of summer with a combination of ice/snow and open water albedo. You should tell me what is the heat absorbing capacity of 4.4% of the Earth's surface area in the mid-Atlantic at the Tropic of Cancer over the northern summer with no ice and open water albedo at much higher incidence angles. Is it more or less than the Arctic? If it absorbs more heat (probably a lot more heat) - why are we all so excited by the Arctic instead of a 4.4% patch of the Earth in the mid-Atlantic?
90135. Ann at 22:00 PM on 5 April 2011
       Upcoming book: Climate Change Denial by Haydn Washington and John Cook
       @28 pierce Say you have a serious illness and the doctor says there are 2 medicins available: one makes your hair fall out, temporarily causes stomac pains and is incredibly expensive. The other medicin is cheap and has no side effects – only it doesn’t work, it has no effect on your disease. What good does it do to discuss “second level arguments” in this case ? If you have 2 alternatives that actually work, you can look at further advantages/disadvantages of the 2 options, and decide for the best option. If there is only one real solution, you go for that solution, and accept all the disadvantages connected to it. The arguments you give are second level arguments. We can start discussing them from the moment you present an alternative approach that actually works. Climate change mitigation is going to be painful (although this strongly depends on the policies our governments will implement, and on the resourcefulness of our science and technology), but it is the only medicin around.
90136. Ken Lambert at 21:38 PM on 5 April 2011
       Arctic Ice March 2011
       "Tom Curtis #86 at 00:41 AM on 5 April, 2011 Just to put Ken Lambert's line of argument into perspective, the additional 0.01% of the Earth's surface that is exposed ocean rather than ice in the Arctic due to warming over the last 30 years absorbs an additional 1.34 * 10^22 Joules of energy each summer. That in turn is enough to melt 4 * 10^13 tonnes of ice, or 14 million square kilometers of sea ice with an average depth of 3 meters. That is nearly three times the extent of sea ice at the minimum in 2007, and more than two times the extent at the minimum of 2011. Tom Curtis - your Arctic heat absorption numbers are wrong by two orders of magnitude. ie. 149 times. Dr Trenberth's (Aug09 paper)estimate of Sea ice loss for the period 2004-08 is 0.9E20 Joules/year. Your number of 1.34E22 Joules/summer is equal to 134E20 Joules/summer. Presumably there is no heat absorbed in winter so your summer number equals per year. So we compare Dr Trenberth's 0.9 with your 134. Your figure is 149 times Dr Trenberth's. The heat energy gained by the *whole planet* is (again Dr Trenberth's figure of) 145E20 Joules/year which equates to 0.9W/sq.m of warming imbalance at TOA. I quoted an Arctic sea ice figure of 1.0E20 Joules/year being 1/145th of the total global energy imbalance in an earlier post. This was from Table 1 of Dr Trenberth's Aug09 paper "Tracking Earth's global energy". The 0.9 number was rounded to 1.0 for the table. I suggest you familiarize yourself with it, and adjust your numbers downward by two orders of magnitude.
90137. CBDunkerson at 21:19 PM on 5 April 2011
       Climate myths at the U.S. House Hearing on climate change
       chriscanaris, given that Judith Curry is working on the 'BEST' project with Muller, and has a similar history of making provably false statements herself, I'm not sanguine about her 'nuanced' response. That said; Curry, Muller, Spencer, and a few others fall into a category of scientists who have staked out an ideologically contrary position and displayed clear bias in defending it. Yes, they are a step above true denialists like Singer in that when faced with overwhelming proof that they are incorrect they still have enough integrity to say so... but the fact remains that they're spreading outright misinformation. The two Muller statements quoted in the article above are clearly / provably false... and that makes him part of the problem. Until he starts checking 'skeptic' talking points, with the same rigor that has gone into the BEST study, before repeating them he is prostituting his scientific credentials in favor of a political agenda. Muller and Curry are finding out the truth behind the old adage, 'you lie down with dogs, you wake up with fleas'.
90138. Peter Hogarth at 21:19 PM on 5 April 2011
       Soot and global warming
       Chris S at 18:51 PM on 4 April, 2011 The Lamarque 2010 paper linked in "here" (comment 21 above) describes a new global historical (back to 1850) gridded anthropogenic and biomass burning aerosol emissions dataset (Bond is co-author) and Bond 2011 also offers a more updated geographical breakdown, including the significant contribution from Europe (see section 4.5 on the Arctic). This paper also contains a wealth of other information and references.
90139. les at 21:03 PM on 5 April 2011
       Arctic Ice March 2011
       101 CBDunkerson "No one could be that absurd." Although I find that much of what you write has great insight and respects empirical results; this last remark clearly contradicts the evidence.
90140. CBDunkerson at 21:03 PM on 5 April 2011
       10 key climate indicators all point to the same finding: global warming is unmistakable
       RickyPocket: "I still doubt the cause as to whether 'Global Warming' is the result of; Solar influences." As this 'possibility' is overwhelmingly disproven by evidence supplied in the, It's the Sun, argument response at the very top of the 'skeptic' arguments list it is clear that you have not bothered to read up on the science or this site at all. Thus I would hope that the moderators remove your copy/pasted manifesto (and this reply) as pure spam. It contains nothing more than a laundry list of the usual provably false 'skeptic' claims already addressed on this site.
90141. CBDunkerson at 20:55 PM on 5 April 2011
       Arctic Ice March 2011
       Gilles: "And finally I'd like to stress that the decrease of multi-years old ice is just the logical consequence of a pronounced minimum some years ago - it proves nothing more. If the minimum stabilizes, the multi year ice should also stabilize or recover." Since the "pronounced minimum" in 2007 the extents in 2008, 2009, and 2010 were all higher... yet multi-year ice and total ice volume continued to decline. Your postulate is thus disproven by already observed reality. Indeed, everything you have said in your last several comments on this thread is so terribly ridiculous as to make it difficult to credit that you could actually believe it. You are seriously arguing for Arctic sea ice recovery on the basis of a one week anomaly? No one could be that absurd.
90142. Gilles at 20:00 PM on 5 April 2011
       Arctic Ice March 2011
       adelady, I know there is a trend + variability. I'm saying that there is no clear indication of positive feedbacks since large excursions below the trend are not followed by an exponential decrease, going and faster and faster, but are generally followed by a return to the trend. The trend itself is measured only with the accurate satellite measurements, which weren't available before - so as I said it is very difficult to give a precise estimate of the natural noise. Unless you know perfectly the amplitude of spontaneous variability at this particular frequency (30 yrs)-1 , you can't say if it is significative or not. Just a remark : the decrease has accelerated at the very time when global temperatures seemed to stabilize , or at least did not accelerate. So it's not obvious at all that both are correlated. Another remark is that there is much less variation in extent around mid-May - so actually the variations of minimal extent are due to the last weeks just before the minimum - it is not obvious at all that this is linked with any "memory" of previous years. And finally I'd like to stress that the decrease of multi-years old ice is just the logical consequence of a pronounced minimum some years ago - it proves nothing more. If the minimum stabilizes, the multi year ice should also stabilize or recover.
90143. h pierce at 19:29 PM on 5 April 2011
       Upcoming book: Climate Change Denial by Haydn Washington and John Cook
       Marcus at 13 Boats, planes, freight trucks and trains, heavy machinery used in agriculture, construction, forestry and minning, emergency and military vehicles, cars and light trucks with spirit and muscle (i.e., V-8's) personal rec vehicles (e.g., ATV's) and so forth will always use hydrocarbons fuels because these fuels have high energy density. The fossil fuel industry will be unaffected by any so-called climate change mitigation. They will pass any costs to the consummer. BTW tell me how to smelt economically iron ore without the use of coke. Or mine diamonds and gold without the use of mega gobs of diesel.
90144. adelady at 18:57 PM on 5 April 2011
       Arctic Ice March 2011
       Gilles@96 Go back to the OP and have a look at "the tale of the tape" (just below the Kara Sea pic). It really is necessary to go to CT so you can look at the full width display. And at http://img215.imageshack.us/f/ctarcticareato150111.png/ here's a graph I asked a friend to prepare based on 'tale of the tape' to clarify the apparent trend in the anomaly graph as presented. As for the apparent uptick during the last week! That's just like weather, heatwaves, rainfall, whatever in a particular location. You're clearly not an ice-watcher, otherwise you'd know that there's a lot of excitement from time to time about possibilities of double or triple apparent minima/ maxima. (if anyone wants to properly link that imageshack thing, go ahead. My clumsy and clueless approach led to me invoking the three strikes - out! rule.)
90145. h pierce at 18:44 PM on 5 April 2011
       Upcoming book: Climate Change Denial by Haydn Washington and John Cook
       Probably due to shipping costs. Qz is far away from cities where books are printed.
90146. Gilles at 18:18 PM on 5 April 2011
       Arctic Ice March 2011
       "Back on topic: I'll go with Tamino with a predicted minimum sea ice extent approximately equal to that in 2008." I'll predict that you will be approximately right.
90147. Gilles at 18:16 PM on 5 April 2011
       Arctic Ice March 2011
       #95 But it takes unmitigated gall to interpret "x is a positive feedback" as "x is a positive feedback and is the only influence on events" the only meaningful question is that if this positive feedback has a significative impact on the curve, or not. If yes : where do you see it ?
90148. Gilles at 18:11 PM on 5 April 2011
       Arctic Ice March 2011
       I am just talking of the last week increase, that appears just at the end of the curve of sea ice area. There is no clear sign of feedbacks amplifying the variation, in my sense. Now concerning the interpretation of the decrease, I'd like to point out something important : it is generally impossible to interpret a variation over a period T if you don't have many similar periods of comparable lengths to compare with. A curve such the above graph for september extent looks very like the curve of the temperature during an afternoon or during the six last months of one year. However nobody would worry about them, because we know that these variations are "normal" in the sense that they belong to a periodic pattern , that we can easily detect on a many years basis. But without a much larger period of observations, it is impossible to know if this periodicity exists (or at least the amplitude of random fluctuations around the average ) . So the above graph can only be interpreted if you have an idea of the natural variance of the signal BEFORE the measurement, so that you can express the variation as a signal to noise ratio. So : what is the natural noise of this curve before the beginning of measurements, at this time scale ? so we have accurate measurements of it ?
90149. Gilles at 18:00 PM on 5 April 2011
       CO2 limits will make little difference
       the whole post is just mixing up three different notions * reduction of energy intensity * reduction of annual rate of global emissions * reduction of total emission integrated over the century. so in the example of Nash equilibrium, one should first careful define which of the previous "reduction" it addresses. In my opinion, the constant failure of international discussions about "reduction" is simply due to the fact that this is never well defined.
90150. Tom Curtis at 17:58 PM on 5 April 2011
       Arctic Ice March 2011
       Gilles @93, it takes a very creative imagination to see this graph as "stabilization": It takes an even more creative imagination to see the slight uptick in sea ice extent over the last week as being the start of a recovering trend, rather than just a minor fluctuation like the seven similar upticks that preceded it. But it takes unmitigated gall to interpret "x is a positive feedback" as "x is a positive feedback and is the only influence on events" so that you can conclude that "the effects of x should result in a monotonic trend". Especially when the positive feedback is dependent on the strength of insolation, which is currently about a third of the summer peak. The question you should really ask yourself is how stupid to you think climate scientists are? Do you really think they would make a prediction of a monotonic trend when any glance at a graph shows the trend to not be monotonic? They are clearly not that stupid, so your attempt to interpret their views as though that was the prediction is either shere folly, or unmitigated mendaciousness. Back on topic: I'll go with Tamino with a predicted minimum sea ice extent approximately equal to that in 2008.

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