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Comments 76451 to 76500:

76451. Steve Case at 00:03 AM on 29 August 2011
       Sea level rise is decelerating
       Tamino did not address the totality of the data, he left off the last 20 years. He used 1880 to present for his calculations, but only graphed them up to 1990. Had he actually addressed the totality of the data in his graph it would have had a time line up to the present and the distortions would have been plainly obvious.
76452. Kevin C at 00:03 AM on 29 August 2011
       Lessons from Past Climate Predictions: IPCC FAR
       Charlie: If you rescale figure 4 to be 712 pixels high and superpose it on figure 3, you'll see that the projections are identical. I presume therefore that the calculation here is just a simple rescaling to fit the current GHG levels, without redoing the whole calculation. As you've obviously realised, that's a very crude approximation, since it changes the hindcast values, and in reality the forecast values will also be slightly out because of the lagged effects of the rescaled earlier emissions. And I'm guessing you're already thinking about the following: If the forcings and projections are both available, then we can deduce the response function of the IPCC model and redo the calculation properly. That would be an interesting exercise. I see a problem however - the curves are not very featureful, and so the response function may be ill determined.
76453. Steve Case at 23:47 PM on 28 August 2011
       Sea level rise is decelerating
       I posted the full satellite record.
       Response:

       [DB] In your desire to prosecute your agenda, you continue to cherry-pick by only using a small portion of the data available. 

       That is muoncounter & Tom Curtis' point, and the entire point of this post you are commenting on.

       If you want to be taken seriously, you will have to rectify that & address the totality of the data, as Tamino did.

76454. critical mass at 23:26 PM on 28 August 2011
       Climate Ethics: What Can Science Tell Us?
       Badgersouth #5 If the current drought in the horn of Africa was attributable to climate change, would not any drought in the last 30 years of official human induced global warming also qualify? ENSO - La Nina cycles play large part in the drought/flood story on either side of the Pacific so also affecting world climate.
76455. Tom Curtis at 23:06 PM on 28 August 2011
       Sea level rise is decelerating
       Steve Case @9, congratulations. You have taken a curve bracketed by the Mount Pinatubo eruption at one end, a cluster of strong La Nina's a the other, and with a number of strong El Nino's in the middle. Unsurprisingly the rate of sea level rise from the Pinatubo low to the El Nino highs is slightly greater than the rate from the El Nino highs to the La Nina lows. If you take a longer data set, as Tamino did you find that sea level rise is accelerating, just as Tamino shows. Now you may insist that we should pay more attention to the shorter trend. However, the shorter trend shows a strong dependence between mean sea temperatures and sea level heights. That is not a comforting thought for the future.
76456. muoncounter at 22:47 PM on 28 August 2011
       Sea level rise is decelerating
       Steve Case#9: "add a second order polynomial Trend Line" Add all the higher orders you like, but be sure to check if they are statistically significant add-ons. That's exactly what was done by tamino; apparently you still have not read that post in full. That would be far more conducive to a rational discussion than any further announcements of your intent to ignore relevant critiques. In the quest for significance, you would do well to consider the work of Kemp et al 2011: Sea level was stable from at least BC 100 until AD 950. Sea level then increased for 400 y at a rate of 0.6 mm/y, followed by a further period of stable, or slightly falling, sea level that persisted until the late 19th century. Since then, sea level has risen at an average rate of 2.1 mm/y, representing the steepest century-scale increase of the past two millennia. I'd suggest, as others threads already have, that long-term pattern is described accurately as 'accelerating.' And that does not even reflect the 3.2 mm/yr from the graph you posted above.
76457. Steve Case at 22:22 PM on 28 August 2011
       Sea level rise is decelerating
       Ok, if you want to discuss things that are not, the title of this discussion is: Is sea level rise accelerating? If you go to the CU Sea Level Research Group you will find this chart: and a link to the data: Raw data (ASCII) If you plot that data out in Excel with 60 day smoothing just like Colorado Research Group's chart and add a second order polynomial Trend Line instead of a linear trend, it will look like this: I would say that according to that sea level is not accelerating.
       Moderator Response: [mc] Reset image width to 450
76458. michael sweet at 21:58 PM on 28 August 2011
       Lessons from Past Climate Predictions: IPCC FAR
       Ken, The link to the IPCC model description is highlighted in blue in the second paragraph of the lead post. In 1990 it was not the custom to post the algorithms and source code, but a detailed description of the models exists so that you can reproduce their data if you wish. Unfortunately, in the past 5 years once the algorithms were posted online skeptics have chosen not to examine them. The answers to your second post would be in the IPCC FAR report if you read it. Complaining that you do not understand how the data was graphed when you have not read the original report does not make a very convincing argument. Since the graph is of projections made in 1990 they are probably centered on the 1960-1990 time period, but they might be centered 1950-1980. The projection is below the measured line at the start of the graph because they do not perfectly model the data. Using my eyecrometer it seems that they are pretty close to the measured data. We are now seeing how well they projected into the future.
76459. Tom Curtis at 19:55 PM on 28 August 2011
       Sea level rise is decelerating
       Steve Case @7: 1) You say:

       "What about disputing the use of ever shorter trends as a means of establishing that change? That's what Tamino has done when he computed the linear trend rate for all possible starting years from 1880 to 1990, up to the present."

       That is not what Tamino has done. Tamino is testing a particular claim, ie, that the rate of change in global sea level has decelerated over the course of the twentieth century (or at least since 1930). Plotting the trend to end point for each year in succession will, as you suggest, exagerate the magnitude of more recent trends relative to older trends. It will show greater variability in the more recent trend. But it will not determine whether the recent trends are larger than the long term trend, or smaller. If in fact the rate of change of sea level was decelerating as is claimed by Houston and Dean, then the most recent trends would be smaller than the long term trends, and plotting a graph such as Tamino's third figure will show a steady line falling away towards zero at the end. So if that is your point, you have no point. You would do well to reread Tamino's post and pay attention to the other more important statistical techniques Tamino applies to determine the evolution of the rate of change of sea level over the 20th century. 2) If you want to introduce your chart as evidence, you need to defend its construction. If you don't want to defend its construction, you ought to withdraw it. As it stands, however, it appears you want to make use of a graph in which artifacts of the data will introduce a very large amount of noise. If you are simply trying to make a logical point about Tamino's analysis, I do not understand why you insist on the accuracy of your graph when you could make the same points using the graph provided by DB inline @1. You, however, insist on sticking with your graph, which makes me suspect some feature of that graph is important to the point you are trying to make. But to the extent that your graph differs from that supplied by DB, there is very good reason to think that the difference is due to noise introduced by your methods.
76460. Steve Case at 18:45 PM on 28 August 2011
       Sea level rise is decelerating
       #6 Tom Curtis. Tom, Thank you for not disputing the use of twenty year trends as a means of establishing the change in global trends. What about disputing the use of ever shorter trends as a means of establishing that change? That's what Tamino has done when he computed the linear trend rate for all possible starting years from 1880 to 1990, up to the present. The resulting graphic effectively ignores any changes in global trends early in the century and magnifies more recent changes. Had the graphic included points derived in that manner since 1990 the magnification and distortion would been gross and apparent. The PSMSL data is arranged by coast line and geographic coordinates which allows the user to perform more than a simple mean. There are 167 coastlines reported. Coast lines have anywhere from one to 77 reporting stations. For each coast line for each year I took the average. The geographic coordinates allow an estimate of each coastline size and application of an appropriate weight for each. For each year I took the median of all 167 coast line averages. That's not to use your assessment, a simple average. I also applied the Peltier GIA adjustment to the GLOSS stations. I found out that it increases the slope by about 0.5 mm/yr but does not otherwise change the shape of the timeline. I would like to analyze the Domingues et al data of those around 500 tide gages. But as is the case in many data files, special programs are needed to unlock them. And so far they are unavailable to me. By the way, the PSMSL data is over 1200 tide gages. I intend to ignore any further critiques you have about the PSMSL data as it's not the issue. And the issue is method. Using unequal sample sizes as Tamino did that magnify recent changes and ignore earlier ones results in a gross distortion.
76461. dansat at 15:37 PM on 28 August 2011
       Climate Sensitivity: Feedbacks Anyone?
       Hansen and Sato's paper was excellent and Hansen writes in a very straight forward way with no need to impress. He uses technical terms only when they are appropriate and this makes his papers very readable. While the sceptics go crazy about the models, they tend to forget that the predictions of AGW are based more on the temperature response to delta CO2 in the past. To disprove climate change, you have to show why this is no longer valid in today's world. The only difference is the speed of the change which the models can be very helpful in deducing. In short, the physics says what the physics says.
76462. scaddenp at 15:04 PM on 28 August 2011
       GHG emission mitigation solutions - a challenge for the Right?
       Camburn - no you didnt propose a solution. You mentioned one of the technologies that could be a solution, but you failed repeated requests to explain the political side of the equation that would result in nuclear being built instead of coal. "I would support" doesnt cut it. I would support a crimeless society too but first you actually have to explain how you get there. Stations are not built because someone in government thinks its a good idea. You have to explain how you break the barriers that currently restrict nuclear. If you were elected tomorrow, how would you do it? I cant take your idea seriously till you say that and address some of the questions that you have ignored in earlier posts.
76463. Bob Lacatena at 13:50 PM on 28 August 2011
       GHG emission mitigation solutions - a challenge for the Right?
       121, Camburn,

       I proposed a very effective solution. ... met with so much resistance. Mindless....and by doing so it makes any problem with co2 seem irrelevant.

       This is false. First, you didn't propose an effective solution, you proposed one single technological option -- Thorium reactors. That this one, single solution can't possibly work all by itself doesn't seem to matter to you. But beyond this, you were asked for further aspects of this... how do you implement this? The government does it and raises taxes to cover it? You just suggest it be done? How does this translate into vehicles? What do you do about the nuclear waste? Is the technology absolutely proven? Or is more research (and therefore delay) required? Your last statement... which basically amounts to the feeling that since people don't agree with you, it therefore means their concern about CO2 is disingenuous... is insulting and offensive. Or did I misunderstand what you meant by that?
76464. adelady at 13:17 PM on 28 August 2011
       GHG emission mitigation solutions - a challenge for the Right?
       Camburn "...because of the resistance of numerous groups that only want wind/solar/thermal to be used for energy..." I'm not a group, not even a member of a group, but my 'resistance' may be very similar to others. I see fast, anywhere & everywhere rollout of renewables as the 'low-hanging fruit' of getting emissions down as quickly and as cheaply as possible. If we do it as fast as possible, that's an incentive for entrepreneurs to get in on the act and help drive costs down even faster with their own innovations. Like others I believe that it's possible to go entirely renewable across the world. But I also think it's worth keeping nuclear development going at the same time - to slot into the system in countries/areas where renewables are difficult to build or it's way too expensive to transmit renewable power generated elsewhere. (And it's worth keeping the peace at home with a man obsessed by the wondrous possibilities of salt-cooled thorium reactors.)
76465. RW1 at 12:49 PM on 28 August 2011
       Climate Sensitivity: Feedbacks Anyone?
       DB, "It is rather simplistic thinking to compare the Arctic, a maritime region largely comprised of ocean, with the Antarctic, a glaciated plateau, and expect them to react similarly to this early phase of AGW." Sorry, I mean Antarctic sea ice extent.
       Response:

       [DB]

       Try Is Antarctica gaining or losing ice? for a discussion on Antarctic sea ice changes and the causes of the same.

       BTW, Antarctic Sea Ice now (when it should be at maximum) is currently at a low point:

       

       [Source]

       Let us get back to the topic of this thread, Climate Sensitivity: Feedbacks Anyone?.

76466. muoncounter at 12:49 PM on 28 August 2011
       Climate Sensitivity: Feedbacks Anyone?
       RW1#8: "calculate the increase in absorbed solar energy" You might consider a different strategy on this question this time around. Rather than your calculation-based approach -- which is, in all reality, just a model with its own simplifying assumptions -- take a look at what has actually happened. Perovich et al 2008 There was an extraordinarily large amount of ice bottom melting in the Beaufort Sea region in the summer of 2007. Solar radiation absorbed in the upper ocean provided more than adequate heat for this melting. An increase in the open water fraction resulted in a 500% positive anomaly in solar heat input to the upper ocean, triggering an ice–albedo feedback and contributing to the accelerating ice retreat. The melting in the Beaufort Sea has elements of a classic ice–albedo feedback signature: more open water leads to more solar heat absorbed, which results in more melting and more open water. The positive ice–albedo feedback can accelerate the observed reduction in Arctic sea ice. This is what is happening: No models needed. The feedback is there; a baseline sensitivity already exists. Have a good long listen to Denning's video: Arguing about a few decimals of sensitivity almost seems silly at this point.
76467. Camburn at 12:37 PM on 28 August 2011
       GHG emission mitigation solutions - a challenge for the Right?
       I proposed a very effective solution. However, because of the resistance of numerous groups that only want wind/solar/thermal to be used for energy, it may not be possible. Such a simple solution met with so much resistance. Mindless....and by doing so it makes any problem with co2 seem irrelevant.
76468. RW1 at 12:28 PM on 28 August 2011
       Climate Sensitivity: Feedbacks Anyone?
       DB, "Tell that to the Arctic Sea Ice, which has lost more than 50% of its thickness in the past decade alone, or to the GIS which continues to lose mass at an accelerating rate." OK, calculate the increase in absorbed solar energy from the melting Artic ice that has occurred and explain how the 'feedback' caused this much melting occur, and then show how this effect is proportional to that which occurs when the planet leaves maximum ice. You should also explain why the 'feedback' hasn't caused any melting in Antarctica.
       Response:

       [DB] It is rather simplistic thinking to compare the Arctic, a maritime region largely comprised of ocean, with the Antarctic, a glaciated plateau, and expect them to react similarly to this early phase of AGW.  And you wrong in implying that Antarctica is losing ice (hint: both the WAIS and the EAIS are losing mass).

       So for starters, try reading these: Ice isn't melting and What causes Arctic amplification?

       An attitude of actually trying to learn about things and asking questions instead of speaking negatively about subjects that it is apparent you lack full understanding about will get better results.  But that would imply that you are here to learn, which is something that you have already stated that you are not here to do...

76469. grypo at 12:10 PM on 28 August 2011
       Climate Ethics: What Can Science Tell Us?
       daisey "There's no connection between Al Gore, climate science, and morality/ethics (except in the minds of propagandists and the naive)." I don't understand your logic. Upon what "connection" would you need? Gore was the first to get people in the wider community discussing climate change as an ethics issue. Anybody can discuss the ethics of climate or the science. Could you please make your argument follow logically before accusing many people of being "propagandists"?
76470. Ken at 12:05 PM on 28 August 2011
       Lessons from Past Climate Predictions: IPCC FAR
       In Figure 5, why is the IPCC projection linear with slope changes in 2000 and around 2008? Also, why does the IPCC projection after 1880 have two sharp linear slope changes when actual data in this time period was nowhere as complete or accurate as today? How did the IPCC have data to use energy balance/upwelling diffusion ocean models to make projections in this time period? For scientific accuracy, I believe all these charts should show the key years when data collection methods and quality of data changed. After all, science is supposed to be about the data and vetting that data, not who is stating conclusions about the data. In Figure 4, how can a projection be below the actual at the starting point of the projection? There has to be a known starting point where both values were equal.
76471. RW1 at 11:32 AM on 28 August 2011
       Climate Sensitivity: Feedbacks Anyone?
       "Model estimates come with large error bars that have proven difficult to reduce as climate models have become more realistic over the decades, because modeling all the positive and negative feedbacks is so complicated. However, the paleoclimate record allows us to circumvent that problem, as past climate changes obviously included all existing feedbacks." I really doesn't, as I've illustrated in comment #6.
       Response:

       [DB] "I really doesn't, as I've illustrated in comment #6."

       Not hardly.

76472. RW1 at 11:23 AM on 28 August 2011
       Climate Sensitivity: Feedbacks Anyone?
       With regard to the glacial to interglacial sensitivity, one can’t equate the positive feedback effect of melting ice from that of leaving maximum ice to that of minimum ice where the climate is now. There just isn’t much ice left, and what is left would be very hard to melt, as most of is located at high latitudes around the poles which are mostly dark 6 months out the year with way below freezing temperatures. A lot of the ice is thousands of feet above sea level too where the air is significantly colder too. Unless you wait a few 10s of millions of years for plate tectonics to move Antarctica and Greenland to lower latitudes (if they are even moving in that direction), no significant amount of ice is going to melt from just a 1 C rise in temperature. Furthermore, the high sensitivity from glacial to interglacial is largely driven by the change in the orbit relative to the Sun, which changes the angle of the incident energy into the system quite dramatically. This combined with positive feedback effect of melting surface ice is enough to overcome the strong net negative feedback and cause the 5-6 C rise. But we are very nearing the end of this interglacial period, so if anything the orbit has already flipped back in the direction of glaciation and cooling.
       Response:

       [DB] "There just isn’t much ice left, and what is left would be very hard to melt, as most of is located at high latitudes around the poles which are mostly dark 6 months out the year with way below freezing temperatures."

       Tell that to the Arctic Sea Ice, which has lost more than 50% of its thickness in the past decade alone, or to the GIS which continues to lose mass at an accelerating rate.

       "But we are very nearing the end of this interglacial period, so if anything the orbit has already flipped back in the direction of glaciation and cooling."

       Unsupported assertion (prove it).  By all means, show us where in the past where there has been a CO2 excursion such as mankind has introduced into the carbon cycle in the past 150 years (at a rate 10 times higher than occurred during the PETM).

       Furthermore, evidence is already accumulating that we not only have already skipped the next glacial cycle, but will soon have managed to prevent the next 5 glacial cycles.

       So much for the "cooling" direction.

76473. adelady at 11:08 AM on 28 August 2011
       Climate Ethics: What Can Science Tell Us?
       daisym "The Bad News: Because immorality IS sustainable, it will forever be with us." And so will intelligence, cooperation, foresight, common sense, organisation, kindness, curiosity, generosity, selfishness, foolishness ...... Just because we're not perfect doesn't mean we can't meet a challenge. Someone I know had very good advice for his employees ... "It doesn't have to be perfect. It does have to be done." Same goes for our response to the challenge of climate change. We have to do it. If we make mistakes along the way, we acknowledge it and get on with it anyway.
76474. Tom Curtis at 11:03 AM on 28 August 2011
       Climate Ethics: What Can Science Tell Us?
       daisym @8 makes an impassioned plea against deficit spending. I have no problem with that, by why is she fixated on monetary deficits. Money is after all just a marker for the real elements of the economy, productive work, resources and goods. A long term deficit in any of these will have long term adverse impacts in the future. So, if we rip iron out of the Earth and sell it, unless the resultant economic growth in assets compensates for the value of the Iron, we are deficit spending. Without that increase in economic assets, our descendants will be in the same position we are, but without the iron to sell. That is, they will be poorer because we have payed for our consumption with long term assets. The same problem arises with environmental issues. A farmer who raises a crop with practices that result in his fields being contaminated with salt is deficit spending. It does not matter if he makes a temporary monetary profit, his assets are eroded and his long term financial prospects are bleak. And if we, by emissions of GHG destroy acidify the oceans, destroy the great tropical rain forests, and make large areas of the Earth seasonally uninhabitable, we are deficit spending - like it or not. What puzzles me is, why does Daisym think we can't afford to tackle the real deficits based on her monetary fetish?
76475. muoncounter at 10:58 AM on 28 August 2011
       Climate Ethics: What Can Science Tell Us?
       daisym#8: "spend even more money it doesn't have for switching to more costly alternative fuels it doesn't want." I don't know about you, but the power I want has to be on. That's not an ethical concern. Its hot here in Texas (I measured 109F in my backyard today). Oddly enough, it seems to be alternatives that are keeping the power on when conventional power sources can't cope with the heat. "the money just isn't there" That's like saying the money isn't there for weather satellites and hurricane warning systems. Until there's a big enough crisis; then you'll be crying 'why didn't you warn us?'
76476. John Hartz at 10:38 AM on 28 August 2011
       Republican Presidential Candidates vs. Climate Science
       @muoncounter#79 Yes, the paragraph that I excerpted from Parker's column are her words, not Perry's.
76477. R. Gates at 10:20 AM on 28 August 2011
       Climate Sensitivity: Feedbacks Anyone?
       This was an excellent post, thanks for the summary of the Hansen & Sato paper. I have thought about this issue of forcings vs. feedbacks for quite some time, and especially in the case of CO2, it seems the distinction as the whether it is a forcing or a "hyper" positive feedback in the case of anthropogenic release of CO2 seems not to really matter. One could argue, for example, that the rise of human civilization was a result of this particular interglacial, and as such, our release of extra CO2, is simple a biogenic effect on climate not unlike the relationship between plankton and DMS, but simply a positive rather than negative feedback. Homo sapiens, during this particular interglacial, as a biological entity on earth, were primed for civilization to arise. Had the interglacial never occurred, with the subsequent rise in farming and agriculture, it is doubtful that we would have gotten to the point of being able to advance our civilization enough to have the ability to release large amounts of carbon into the atmosphere. In this sense, with the climate as a system on the edge of chaos, some little change from one interglacial to another (like a species being ready for the advance of civilization) is simply a outlier, or black-swan event that takes this particular interglacial in an entirely different direction. In a very real sense then, the Milankovitch cycle leading to this interglacial, was the trigger that brought about the initial conditions, which through initial positive feedbacks of CO2, ice cover reduction, etc. lead to a "hyper" positive feedback situation which seems to be entirely changing the nature of this particular interglacial.
76478. Tom Curtis at 10:18 AM on 28 August 2011
       Sea level rise is decelerating
       Steve Case @3, even if the method were appropriate, the fact that you use unrepresentative data both in time and space means your analysis is not indicative of global twenty year trends in sea level rise. Go to the PSMSL page on relative trends, and use the slider on the bottom and you will see what I mean. Take on example. In 1930, East Asia is represented by just six gauges, all in Japan. By 1970 it is represented 88, mostly in Japan and South Korea. At no time is a simple mean representative of East Asia geographically, and the weight assigned to East Asia (or more particularly Japan) in a global average changes continuously over the period 1930 to 1970. So, while I am not disputing your use of successive 20 year trends as a means of establishing the change in global trends, I am disputing your use of a data set which is never geographically representative, and which changes the representation of various regions over time in order to determine those trends. As ever, DB provides the best information, and you would do well to look carefully at the second figure (fig 8) in his inline comment. Applying 16 year trends on a consistent and representative data set shows a very distinct pattern to that shown from your simple mean of the PSMSL data set.
76479. Bob Lacatena at 09:58 AM on 28 August 2011
       Climate Ethics: What Can Science Tell Us?
       8, daisym,

       ...no matter how righteous is the need to "save the planet", the money just isn't there.

       Except we're not talking about saving the planet, we're talking about saving millions (hundreds of millions?) of people, and the way of life we've developed, and civilization as we've defined it. At the same time, the expense is no where near what you imply, and it is less than what it will cost to ignore the problem for now and pay later. To completely ignore the problem now is to guarantee that the problem grows to unacceptably costly proportions. Your entire position is based on a series of faulty premises. You need to rethink things. The Good News: Ignoring climate change isn't sustainable, so it will eventually stop. The Bad News: If people (and societies and governments) wait until it's too late to take action, the cost may exceed what we are capable of paying, and the very things that you believe you are protecting now are exactly what you will lose.
76480. michael sweet at 09:52 AM on 28 August 2011
       Arctic Ice March 2011
       Whsmith Here is the data for Arctic sea ice back to about 1900. I see a consistent decrease from about 1950. You claim in 252 that "The 70's were a time of HIGH arctic ice expansion and coverage". Can you point out on the graph where your supposed high point is? If you do not look at the data you can believe anything. Perhaps if you were more informed you would be more concerned.
76481. daisym at 09:29 AM on 28 August 2011
       Climate Ethics: What Can Science Tell Us?
       What a strange way to begin this article. There's no connection between Al Gore, climate science, and morality/ethics (except in the minds of propagandists and the naive). However: Isn't it also immoral and unethical for western democracies to expand their people's current life styles by borrowing against the earnings of future generations? Western democracies are already bankrupt... economically AND morally/ethically. I repeat... the World's great democracies have no more money to sustain today's current social welfare benefits, and there's certainly no more money available to stop future manmade climate change. The Good News: Deficit spending isn't sustainable, so it will eventually stop. The Bad News: Because immorality IS sustainable, it will forever be with us. The real point of this article seems to be that morality/ethics is becoming "code speak" for forcing an imperative upon society to spend even more money it doesn't have for switching to more costly alternative fuels it doesn't want. The Bottom Line: Moral or not, no matter how righteous is the need to "save the planet", the money just isn't there.
76482. michael sweet at 09:27 AM on 28 August 2011
       Climate Sensitivity: Feedbacks Anyone?
       For the last 5,000 years (or more) the Arctic sea ice has been a constant ice sheet over most of the Arctic Ocean. We can see by the current sea surface temperature in the Arctic that this sheet is melting and the temperature is rising rapidly, as Hansen and Sato predict. We do not need to wait for Greenland and the Antarctic to melt for this effect. The Arctic sea ice melt is already decreasing the albedo of the Earth (in addition to the decrease in snow cover in summer). In the fall of 2010 the increase in Arctic temperatures from this effect raised the average temperature of the Earth and contributed to the record temperature for that year. As the Arctic continues to melt this effect will grow.
76483. muoncounter at 08:39 AM on 28 August 2011
       Republican Presidential Candidates vs. Climate Science
       Badgersouth: The results of this survey (yes, another survey) may help explain Perry's position on science. - Most of the Texans in the survey — 51 percent — disagree with the statement, "human beings, as we know them today, developed from earlier species of animals." Thirty-five percent agreed with that statement, and 15 percent said they don't know. - Did humans live at the same time as the dinosaurs? Three in ten Texas voters agree with that statement; 41 percent disagree, and 30 percent don't know. Texas is near the bottom of the class in high school graduation percentage; Guvna P is a product of that system.
76484. muoncounter at 08:10 AM on 28 August 2011
       Republican Presidential Candidates vs. Climate Science
       Badgersouth#78: Just to be clear, you are quoting from Parker's piece, not directly from Perry. I have no trouble believing that's likely to be his position, but he hasn't said it (yet).
76485. Robert Murphy at 08:07 AM on 28 August 2011
       CO2 was higher in the past
       "I am not specialist in the field, and yet according to Craeme Lloyd, Natural History Museum, London, UK more than 99% of all species ever lived on the Earth are extinct at present ... by one reason or another." And that is true, except it says nothing at all about CO2 levels.
76486. John Hartz at 08:00 AM on 28 August 2011
       Republican Presidential Candidates vs. Climate Science
       More on Rick Perry's beliefs... "If we are descended of some blend of apes, then we can’t have been created in God’s image. If we establish Earth’s age at 4.5 billion years, then we contradict the biblical view that God created the world just 6,500 years ago. And finally, if we say that climate change is partly the result of man’s actions, then God can’t be the One who punishes man’s sins with floods, droughts, earthquakes and hurricanes. If He wants the climate to change, then He will so ordain, and we’ll pray more." Source: "Rick Perry, the Republicans’ Messiah?" by Kathleen Parker, Washington Post, Aug 26, 2011 To access this insightful op-ed, click here.
76487. Bob Lacatena at 07:57 AM on 28 August 2011
       Climate Sensitivity: Feedbacks Anyone?
       Kooita Masuda, I'm not sure you're understanding the distinction between a forcing and a feedback well, so I in turn am unsure how to evaluate your logic. A feedback is something that responds to a forcing. A forcing is initiated outside of the climate system. That CO2 can be a forcing and a feedback, under different circumstances, is in no way inconsistent. What matters in the distinction is not the mechanism, but how the mechanism is initiated. Clearly, human burning of long sequestered and naturally unreachable fossil fuels is a forcing, as is (in the broadest sense) the addition of massive amounts of CO2 to the atmosphere through weathering or extremely active volcanic activity. Conversely, CO2 changes that are themselves a response to temperature changes are clearly a feedback, and not a forcing. On your own recommendation, I do not see that your logic follows. Hansen and Sato's comparisons to the current climate system, and warnings of the implications that past climate changes imply, are to me all valid points worth serious consideration. You have not in anyway established a valid basis behind your contention that you "do not recommend following it as if it were a standard of how the climate system (including slow component) is sensitive to forced alteration of the atmospheric CO2 concentration." I think the paper stands well as it is, and needs to be taken very, very seriously by anyone who doesn't want to simply deny any unsettling conclusions.
76488. muoncounter at 07:36 AM on 28 August 2011
       CO2 was higher in the past
       Carbonado#44: "they are presented all over the Internet as 'Evidence No.1'" That should tell you a lot about the quality of those arguments -- and the folks that present them. I'd say the science of using cartoon graphs in place of real data and observation is the real 'climastrology.'
76489. DSL at 07:23 AM on 28 August 2011
       Arctic Ice March 2011
       And, whsmith, what do you mean when you say "HIGH"? Do you mean the rate of expansion was as high as the rate of retreat in the last 15 years? A source and a little more precision would be good for your claim re the 1970s. You might also check out sea ice volume rather than extent. From Macias et al. 2009: "The 20th century sustained the lowest sea ice extent values since A.D. 1200: low sea ice extent also occurred before (mid 17th and mid 18th centuries, early 15th and late 13th centuries), but these periods were in no case as persistent as in the 20th century."
76490. Bob Lacatena at 07:17 AM on 28 August 2011
       Sea level rise is decelerating
       Steve Case: You have fallen into the usual trap of looking first for correlation, and then assuming there must be some mystical if undefined causation behind it. The better approach is to anticipate a cause, through an understanding of the mechanics and physics of the system, and to make a hypothesis, and then to either confirm or refute that hypothesis through correlation (or lack of correlation) in observations. The distinction between the two methods is dramatic, necessary, and where so many denial efforts fail before they even get out of the gate, because the former methodology is founded on ignorance and superstition rather than education and logic like the latter.
76491. Ken at 07:15 AM on 28 August 2011
       Lessons from Past Climate Predictions: IPCC FAR
       Where is the algorithm and source code for the IPCC model published?
76492. muoncounter at 07:07 AM on 28 August 2011
       Arctic Ice March 2011
       whsmith#252: "the 2010 and now 2011 ice coverage should be compared with the 30-year running average, 1979-2009." The nice thing about our world is that such data are readily available. Looking at the September minimum extent, the 30 year mean you requested is 6.63 million sq km, with a standard deviation of 0.88. For 2010, the extent was 4.9 or two std devs below the mean. This year's minimum will likely be in the neighborhood of 4.5, flirting with the record low of 2007. Many people are alarmed at that.
76493. Carbonado at 07:00 AM on 28 August 2011
       CO2 was higher in the past
       RE: The species I am not specialist in the field, and yet according to Craeme Lloyd, Natural History Museum, London, UK more than 99% of all species ever lived on the Earth are extinct at present ... by one reason or another. RE: The two versions of the Graph I cannot dispute that both of the versions are absolute cartoons, but they are presented all over the Internet as 'Evidence No.1' that the CO2 and the global temperature 'are falling'.
76494. whsmith at 06:39 AM on 28 August 2011
       Arctic Ice March 2011
       The 70's were a time of HIGH arctic ice expansion and coverage. Perhaps this was unusual, perhaps not. The time period (2000-2011) has seen a reduction in arctic ice. Perhaps this is unusual, perhaps not. Ice coverage has stabilized for the past four years. The running average for climate variables is 30 years (today’s “normal” temperature is a 30-year running average), so 1979-2009 should be the time base for space-based ice comparisons, not 1979-2000. The space-based observations NOW include one 30 year period, plus two years. To be consistent, the 2010 and now 2011 ice coverage should be compared with the 30-year running average, 1979-2009. Perhaps the present situation does not seem, then, so alarming.
       Response:

       [DB] "Ice coverage has stabilized for the past four years."

       The actual data shows clearly that you are wrong:

       

       [Source]

       Arctic Sea Ice Volume is falling faster than property values on the North Carolina coast...

       We could, of course, take a look at extent melt (H/T to Seke Rob):

       

       Or just ice extent over a longer period of time (like you wanted):

       

       "Perhaps the present situation does not seem, then, so alarming."

       Not if you live in a war zone.  People who have actually taken the time to learn the science and read the literature know differently.

76495. Kooiti Masuda at 06:31 AM on 28 August 2011
       Climate Sensitivity: Feedbacks Anyone?
       An implication of my previous comment: While the new paper by Hansen and Sato contains good points internal to science, I do not recommend following it as if it were a standard of how the climate system (including slow component) is sensitive to forced alteration of the atmospheric CO2 concentration.
76496. muoncounter at 06:15 AM on 28 August 2011
       Sea level rise is decelerating
       Steve Case: Did you read the original post? This is a repost of one written by tamino; it is used here as a rebuttal of work by Houston and Dean. Tamino is simply (and quite effectively) making the point that the authors' conclusions - that sea level rise is linear - are unjustified. The key point is in his last paragraph: the forecasts we should attend to are not from statistics but from physics.
76497. John Hartz at 06:09 AM on 28 August 2011
       A new SkS resource: climate skeptics and their myths
       Yet another reason why Patrick Michaels has to be included in the top tier of climate deniers… "Get Real: Hurricane Irene Should Be Renamed "Hurricane Hype'” by Patrick Michaels, Forbes, Climate of Fear Blog, Forbes, Aug 26, 2011 To access this inane article, click here. How many pounds of crow does Michaels eat during the course of a year?
76498. muoncounter at 06:04 AM on 28 August 2011
       CO2 was higher in the past
       Carbonado#41 Presumably you are referring to the graph posted in comment #6 and at larger scale in #27? This graph is a cartoon; it is not from an authoritative source and is not taken very seriously.
76499. Steve Case at 05:13 AM on 28 August 2011
       Sea level rise is decelerating
       Tom, It's not the data, it's the method. Piling 130 years worth of data into a data point from 1880 and comparing it to a data point from 1990 made up of only 20 years worth of data and then omitting the plot for the last 20 points in the time series, does not make any sense. The graph from such a scheme leads one to believe that sea level rise during earlier periods showed no variation from year to year. That is not the case. At the moment I have no way of downloading the data from the link above. Otherwise I would have used that data to create the plot. I have run the Peltier GIA adjustments on the GLOSS sites from the PSMSL and all it does is increase the slope by about 0.5 mm/yr.
76500. Kooiti Masuda at 05:04 AM on 28 August 2011
       Climate Sensitivity: Feedbacks Anyone?
       There are different views about what the climate system is. And what can be considered as an external forcing to it depends on the definition of system. The terminology that equates "climate sensitivity" with equilibrium response of the climate system to atmospheric CO2 concentration implies such a definition of the climate system that excludes CO2 concentration from variable components of the climate system. If we also treat ice sheets and vegetation as fixed (rather than variable), we can say that we exclude them from the active components of the climate system. We can construct a coupled system of the physical (but not biogeochemical) atmosphere-ocean system (including part of the cryosphere such as seasonal snow cover and sea ice). Then, the sensitivity of this climate system to CO2 concentration as an external forcing, i.e. "fast-feedback sensitivity" in James Wight's text, is meaningful both within science and as a piece of information to be referenced in real-world applications. In the glacial cycles, however, atmospheric CO2 concentration varied, apparently in response to temperature (as well as theoretically certainly forcing to it), and it responded apparently faster than the ice sheet did. So if we include the ice sheet as a variable component of the climate system, it is awkward to treat CO2 concentration as if an external forcing and to discuss the sensitivity. It seems interesting and meaningful as an exercise internal to climate system science to discuss the equilibrium response of the climate system to the change of one of the internal component of the system hypothetically held constant for an indefinitely long time. I doubt that it can be evaluated by simply comparing the values of alleged forcing and alleged response in the paleoclimatic reconstructions. I think that more careful discussion is needed both in theoretical considerations and in interpretations of observational data. Even then, I do not think that such scientific exercise is directly very useful to real-world application. Just insights gained by such exercise will be useful.

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