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Comments 80701 to 80750:
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Camburn at 09:06 AM on 1 July 2011Websites for Watching the Arctic Sea Ice Melt
michael: I would suggest that you get a copy of Capt Henry Larson's log on his voyage traversing the NW passage in 1944. I cannot post a link to his log as it is not available on the web and the museum, the owner of said log, has not given me permission to scan and post it. -
Camburn at 09:01 AM on 1 July 2011Websites for Watching the Arctic Sea Ice Melt
Philippe: I won't go into harmonics or cycles as most folks want to dismiss them. With that said, that is what I am using to base my low ice extent on. The area, volume etc. Cryosat, along with the Gatlin team has found ice thicker than previously thought unless one examines polar 5 data. The trend is as expected based on other criteria to me. The big elephant in the room is the amount of black carbon that China continues to spew. That has lowered ice albedo, and is ingrained in the ice itself. This has added to the degree of melt in a substantial way. BC is anthro in nature, so must be added to effect and cause. ShindellResponse:[DB] I would caution you on hanging one's hat on the initial rollout of Crosat-2 data. In software terminology, it is only a "beta". As a test, consider that the design vertical resolution is in the millimeter range, while the product delivered to date has a horizontal granularity (it has very large pixels) in the kilometer+ range.
Adding to the calibration issues is a highly mobile, fractured and friable ice pack that is continuously shifting, adding to the issues in stitching together data from the separate flight paths.
A layman interpretation is that the current realization of Cryosat-2 data is that it is nearsighted, needing visual corrections to come. Future iterations will likely have improved discrimination capability as the stitching algorhythms evolve (it's eyesight will sharpen).
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michael sweet at 08:54 AM on 1 July 2011Websites for Watching the Arctic Sea Ice Melt
Camburn, are you suggesting that "a long term sine wave shows hamronics" indicates that the sea ice low this summer will be less than 50% of the lowest level recorded before 1940 (see Cryosphere Today) and you think that is normal? Please explain how a sine wave harmonic could result in 50% of the ice melting when the trend was flat for decades prior to that time. Please refer to scientific sources for your data. Please support your reasoning with more analysis than your eyecrometer. Please stop poisoning the scientific discussion on this site with your wild, unsupported speculations.Response:[DB] "wild, unsupported speculations"
The technical term, I believe, is "gibberish".
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Doug Mackie at 08:50 AM on 1 July 2011Ocean acidification: Coming soon
Links fixed -
Norman at 08:45 AM on 1 July 20112010 - 2011: Earth's most extreme weather since 1816?
Tom Curtis @ 171 I would humbly disagree with your calculation. You are using a 5 magnitude (and stronger) earthquake as a disaster causing one to get the calculation of 4% of 2100 earthquakes led to disasters (86 disaster geophysical events in 2010). Yet in your post you show a 5.4 will produce little damage and not lead to a disaster (Borrego Springs Quake). I am not sure at what level in the 5's an earthquake will become a disaster if it strikes a populated area nor do I have the number broken down but it could be a safe speculation that as the magnitude goes up there are a lot fewer so most of the 5's may be lower non damaging earthquakes. For the US you state maybe 2 or 3 were disasters. In the US only 9 had a magnitude of 6 or more. If you go with the higher figure of a 6 magnitude or above earthquake as being reported as a disaster (some will hit in non populated areas) you get 173 for 2010. If the 86 listed geophysical events are earthquakes (a few could be volcanoes) then your number of earthquakes being reported as disasters is now very close to 50% which is the point I was making. Most disaster causing earthquakes are counted already and an increasing population, with higher propery values (disaster reporting is based upon number of people killed and a certain level of property damage) will not have much effect on the number reported. Whereas if only 8% of supercell storms lead to disasters but the potential is for a higher number, a higher number of wealthy individuals will increase the odds of a supercell being counted as a disaster. -
mb at 08:44 AM on 1 July 2011OA not OK part 1
Something seems fishy here... I think the chemistry prior to Eq. 1 (ie, the formation of aqueous carbonic acid from dissolved CO2) could be written like: 2(H2O) + 2(CO2)_g <-> 2(H2CO3)_{aq} <-> 2(H+) + 2(HCO3)^{-}_{aq} Then 2 bicarbonates react with Ca ions to produce shells and returning only 1 CO2 to the atmosphere (the gas phase). Hence, if two CO2s go in, it seems like shell formation is a net carbon sink. Am I missing something? -
Philippe Chantreau at 08:42 AM on 1 July 2011Websites for Watching the Arctic Sea Ice Melt
There is no "slowdown." 2007 saw a sharp acceleration of melt in late june, which is not happening this year. There is plenty of weather yet to come that will determine what the minimum extent of September will be. Whereas the next few years might indeed be telling, I'm hard pressed to see how the past few weren't quite telling as well. "I know you modelers do not like to look at real data becasue it upsets your thinking." Gratuitous, baseless and insulting. You should refrain from such, the usual tone of your posts is much better. -
Eric the Red at 08:22 AM on 1 July 2011Websites for Watching the Arctic Sea Ice Melt
Camburn, Based on the slowdown in Arctic melt compared to 2007 and 2010, and the cold North Atlantic, I so not share your sentiments. I do agree with your harmonics however. The next few years should be telling (not necessarily 26 Sphaerica). -
Tom Curtis at 08:17 AM on 1 July 20112010 - 2011: Earth's most extreme weather since 1816?
Eric, the eyechrometre is not leg work. Unless you at least do a side by side graphic comparison, or better yet run the data through a spread-sheet there is really nothing to discuss. I will note however that your response effectively concedes the connection between temperature and precipitation. Specifically, it makes not claim for explanatory power in the SH, where the larger increase in precipitation must be explained by global warming. And it attempts to explain variation, but not the trend in NH precipitation by warmer NH oceans. Finally, it leaves the trend in NH precipitation to be explained by the trend in temperatures. Given that, even if you do the legwork (which may be interesting), it would probably be more appropriate to another topic. -
Fred M at 07:48 AM on 1 July 2011Ocean acidification: Coming soon
Camburn (#3,#8) suggests that increasing CO2 reduces ocean alkalinity. Yesterday, I tried to explain why that is wrong, but for reasons I don't understand, the comment was deleted. I'll try again. [ -snip-]Moderator Response: (Rob P) See my earlier warning. Try not to respond to provocation - Camburns comments are designed to distract readers from the content of the ocean acidification (OA) posts. This 18 part series will make the details of OA very clear to readers. -
Camburn at 07:38 AM on 1 July 2011Websites for Watching the Arctic Sea Ice Melt
Eric: A long term sine wave shows hamronics in the temperature of the planet. As solar research is getting going, there are not only hints, but the beginning of a credible data base that TSI is constant, but magnetic fields, solar winds, GCR, and it even seems events such as the Carrington, while not pointed at earth still play some type of roll in climate. But that is off topic. I still predict sea ice decline to 3.5 this year. From old Canadian Ice data it would seem that this year "should" be the lowest for quit some time. IF the trend continues as it has, then cycles, as we know them, have been over ridden. -
Camburn at 07:34 AM on 1 July 2011Websites for Watching the Arctic Sea Ice Melt
KR: A bit off topic again, but I talked to the NSIDC center today in realation to Aqua data on earth brightness. They seem very confident that the product they are presenting concerning is credible. They are fairly confident on the ice area as that is actually quit hard to measure even with a satillite. They look forward to sharing data from Cryosat. We live in exciting times. Prob in 100 years someone will look back and think we were in the dark ages, but the tech advances even in the last 10 years are quit marvelous and provide for a contining reliable data set. Another thing I learned that I was not aware off is that the NSIDC has a solar arm to it. The fellow I talked to, his grandfather was one of the designers of SOHO. Thank you for pricking my interest again moreso in earth brightness. It produced a very interesting and worthwhile telephone conversation. -
Papy at 07:29 AM on 1 July 2011Extreme weather isn't caused by global warming
Text from the intermediate level seems broken. -
KR at 07:08 AM on 1 July 2011Websites for Watching the Arctic Sea Ice Melt
Camburn - The difficulties in measuring aerosols are part of the reason aerosol uncertainties (how much negative feedback) are so high. There have been some proposed satellites that could more directly measure aerosols, but they just haven't been launched. However, aerosols do appear to be directly implicated in the mid-century cooling that ended ~1975. -
Camburn at 06:48 AM on 1 July 2011Websites for Watching the Arctic Sea Ice Melt
Dikran: Thank you for the response. I personally don't think it is responsable for >50%. One of the main reasons for this is the sine components within the measured and proxy temp record. But i am getting off topic. KR: I know the theory, but there was no practicle way of measureing the Aerosols during that time frame. I wasn't sure if you had found something new to verify them. Thank you for your response. -
John Hartz at 06:43 AM on 1 July 2011Climate half-truths turn out to be whole lies
@ClimateWatcher #42 Humans Dwarf Volcanoes for CO2 Emissionsis an excellent article on this topic. The gist of the article is: 1. Human activities emit roughly 135 times as much climate-warming carbon dioxide as volcanoes each year. 2. Volcanoes emit less than cars and trucks, and less, even, than cement production. 3. Climate change skeptics have claimed the opposite -
Eric the Red at 06:42 AM on 1 July 2011Websites for Watching the Arctic Sea Ice Melt
Sky, These are not numbers "out of the air," but hard data.I know you modelers do not like to look at real data becasue it upsets your thinking, but sometimes you have to face the facts.It is also much more scientific that mathematical models, as it includes real scientific measurements. The ocean temperatures have been following the land temperatures for the past decade, no heat accumulation. Ice would discontinue melting under such a scenario. Waiting for two decades are your words, not mine.Response:[DB] First off, cease with your baiting. That is simply trolling and you know it.
"The ocean temperatures have been following the land temperatures for the past decade, no heat accumulation."
Factually incorrect. See the Oceans are cooling thread.
Backing up your handwaving assertions with citations to peer-reviewed published sources would bring your credibility out of the negative range. That would be the scientific thing to do.
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KR at 06:41 AM on 1 July 2011Websites for Watching the Arctic Sea Ice Melt
Eric the Red - I have to agree with Sphaerica. In order for your apparently random numbers to work out, two things would have to be true. (1) Another cause for current warming, that fits the various fingerprints, would have to be found. So far, nothing. Not the sun, not GCR's, not reptoids... (2) CO2 would have to not behave as physics predicts, because it's doing just what we expect based on spectroscopy and other measurements. You appear, for some reason, to be hunting for alternatives. I don't know why, and quite frankly it doesn't matter. If they don't have physics and measurements behind them, they are just wishful thinking, and you're wasting folks time. -
adelady at 06:33 AM on 1 July 2011Throwing Down The Gauntlet
Heraclitus - they didn't think it, they said it. My suspicion is that it's just like a car - if it's red, it's the real deal. The reason this one's called a bicycle is that you don't need a license to ride it. It's nowhere nearly as powerful as yours. Not been used for a couple of years now - trying to decide between getting a new battery pack for this one or replacing it altogether. (And on country roads, the car will do 100 clicks going up a hill, the bike can't. With more work around the city, the bike might get the nod again.) -
Bob Lacatena at 06:26 AM on 1 July 2011Websites for Watching the Arctic Sea Ice Melt
132, Eric the Red, As far as your comment on the "committed warming," it is clear that the thermal inertia of the oceans is a factor, as well as the fact that many feedbacks are slow acting, such as changes in albedo due to ice melt, and natural carbon sources that result from ecosystem changes (Amazon to savanna, prairie/grassland to desert, shrinking forests), not to mention potential methane release and other sources. So there is no reason to think for one moment that stopping at 1.3C is going to mean stopping at 1.3C. Indeed, a change to 1.3C in a period of a mere 75 years may have frightening implications, because I'm not sure the temperature of the planet has ever changed at that rate -- ever. As far as your "scientific" label for yourself -- hard numbers, pulled at random from your gut aren't scientific just because they're numbers. I appreciate you thinking that you answered the question, but you really dodged it by setting a time frame that is so distant that your answer is effectively meaningless. As far as what it would take to convince me that warming is not attributable to CO2, the answer is a something amazing, because that would mean that our understanding of the physics is completely wrong, and that there is some element of the physics that we've completely failed to identify. Really, the fact is that the evidence is currently so strong that there is no chance that warming is not caused by CO2. The only viable argument, as you know, is related to overall climate sensitivity, and if thoughtful, well-founded studies were produced that put climate sensitivity at or below 1.5˚C per doubling, and if further studies lent support to and buttressed that conclusion, then I would start to relax. To be more direct about your question about attribution to CO2, I would need to see studies on some utterly silly nonsense like GCRs that actually bear fruit, providing both a viable mechanism and a correlation between temperatures and some measurable values to demonstrate that there is another factor at work in place of CO2. Even if the globe started to cool, that would not be evidence to me that CO2 does not operate as science believes. It would be evidence that there are in fact mysterious and unexpected forces at work that need to be identified and unraveled (and which therefore might then, once understood and quantified, be hoped to mitigate the impact of CO2). This is very unlikely to happen, since by this point in time we seem to have most of the factors pretty well nailed down, everything adds up and the ledger balances. But without an understanding and firm theory of atmospheric physics to support any change in temperature, observations that contradict expected warming point to a puzzle, not to a reason to out of hand dismiss existing theory. -
Tom Smerling at 06:18 AM on 1 July 2011The Climate Show 15: Michael Ashley and the ineducable Carter
Nice piece. I think your even, good-natured tone is very effective -- like you're not trying to "sell" something, and not panicked -- just relating the facts. -
adelady at 06:17 AM on 1 July 2011Websites for Watching the Arctic Sea Ice Melt
"...under such a scenario, the Arctic sea ice would increase." But that's just the atmospheric temperature! Have a look at accumulated ocean heat shown in that graphic. Do you really think that ice would not continue melting from beneath while that amount of heat is still circulating? -
MattJ at 06:15 AM on 1 July 2011Throwing Down The Gauntlet
I understand that there is no longer any room for reasonable doubt, but I also understand that it does NOT help to say, "please read the other 4,372 posts on Skeptical Science." This is especially silly when one of the star strong points of Skeptical Science (SS) is that it IS so well organized that a rational person need not read all 4372 posts to remove all reasonable doubt: such a rational skeptic can find the specific rebuttal he needs to read and focus on that. Let's give SS credit for its achievement: this is a wonderful organization of the data. -
skywatcher at 06:14 AM on 1 July 2011Websites for Watching the Arctic Sea Ice Melt
Eric, you love to set goals far into the future, don't you? Just like in the comments for this thread, you want us to sit back and wait over two decades before you'll decide the evidence is sufficient. You're picking numbers out of thin air and calling them 'hard'. That's not too scientific. I agree with Dikran - the second para is particularly woeful - every climate projection includes contributions from all major forcings, not just CO2. The continuing CO2 trend is clearly visible in every temperature dataset when the other forcings are removed, and is right in line with what the physics tells us. It's not about to start, it's already here and continuing. Pretending that there is some kind of middle ground is just another form of denial, and not in agreement with physics. -
Eric the Red at 05:56 AM on 1 July 2011Websites for Watching the Arctic Sea Ice Melt
( -Snip-). Just to keep this on topic, under such a scenario, the Arctic sea ice would increase.Response:[DB] Off-topic portion snipped.
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KR at 05:53 AM on 1 July 2011Websites for Watching the Arctic Sea Ice Melt
Camburn - Read the link in my post, look at Figure 1. Aerosols increase cloudiness, reduce sunlight reaching the ground, and are a major reason for the 1940-1975 cooling period mid-century, with the temperature anomaly slope reversing around the time of the Clean Air act and similar measures enacted in Europe. In other words, read the references. It's becoming even more clear that you have not. -
Dikran Marsupial at 05:47 AM on 1 July 2011Websites for Watching the Arctic Sea Ice Melt
camburn You are missing the point, the question as phrased was a straw man, it is widely known that CO2 is not the only driver of climate; I don't think anybody is claiming that all of the warming is unambiguously attributable to CO2 radiative forcing. The direct answer to Eric's question as posed is "very little, as I didn't think it was in the first place". Now Eric can make it an interesting question by specifying a ratio, but that is his job not mine. Personally, I am a mainstream science kind of guy, and to find an answer to your question I would probably get my copy of the IPCC WG1 report down from my bookshelf and look it up. However, I should have gone home hours ago. As a conservative estimate, I'd say that CO2 radiative forcing has been the dominant driver of climate since, say 1970, so that would be > 50%. BTW, not all natural variability is cyclical. -
Camburn at 05:35 AM on 1 July 2011Websites for Watching the Arctic Sea Ice Melt
KR: How can you say the aerosol level is negative? What are you basing that assumption on? Dikran Marsupial: What percentage of the warming is from natural cycles if not from co2? -
KR at 05:21 AM on 1 July 2011Websites for Watching the Arctic Sea Ice Melt
Eric the Red - This is discussed in some detail on Has Earth warmed as much as expected. This committed warming is primarily driven by the time for the oceans to warm given the current imbalance. Long story short, we're right about we we should expect for a sensitivity of 3C/doubling of CO2, with an inertial deficit of about 0.6 W/m^2 ocean energy absorption, or roughly another 0.4-0.5 C that we're committed to with the current radiative imbalance (once the oceans catch up). If we were to stop GHG's today, and somehow maintained the current aerosol level, mind you - that's negative 1.2-1.3 W/m^2, and if we suddenly stopped emitting aerosols we would have another >1C warming over 2-10 years. -
Philippe Chantreau at 05:05 AM on 1 July 2011Throwing Down The Gauntlet
Eric's post is interesting. There are so many ways to conserve and make the entire system more efficient it's not even funny. These low hanging fruits can really go a long way and should be the first thing to be addressed. It has the advantage to be empowering and satisfying for individuals and applicable regardless one recognizes AGW or not. Next, it would be nice if the kind of creative ingenuity displayed for instance by the Enron traders to screw their customers could be instead applied to optimize the grid. That will not happen without some sort of incentive. -
Dikran Marsupial at 04:57 AM on 1 July 2011Websites for Watching the Arctic Sea Ice Melt
Eric the Red. Look at the projections of climate models. The committed warming is already happening, it is gradual and doesn't "kick in". The second paragraph is specious, without specifying a minimum proportion that is not attributable to CO2, the question is meaningless. Has anyone said that 100% of the warming is due to CO2? -
John Hartz at 04:52 AM on 1 July 2011OA not OK part 1
Best to expand the title to either: "OA (Ocean Acidification) is not OK". or "Ocean Aciditfication (OA)is not OK" -
Eric the Red at 04:47 AM on 1 July 2011Websites for Watching the Arctic Sea Ice Melt
Spaerica, When is this committed warming expected to kick in? You keep mentioning that it will occur sometime in the future, but without giving a time table (sounds like your abovementioned cop out). At least I am presenting hard numbers. My presentation was totally scientific, and without denial. Let me turn the tables. What would it take to convince you that the observed warming is not all attributable to CO2? -
Eric the Red at 04:36 AM on 1 July 20112010 - 2011: Earth's most extreme weather since 1816?
Tom, Yes, I did some leg work, that is why I presented the last post. A casual connection does exist between precipitation and either temperature or PDO. Neither is a good correlation statistically, however, the correlation is better with PDO. The only explanatory path for the PDO would be similar as for temperature; increase in pacific ocean temperature wouls enhance NH rainfall. -
Tor B at 04:13 AM on 1 July 2011OA not OK part 1
"Reverse the arrow and Equation 3 becomes Equation 2." Do you mean #2 becomes #3? -
Bob Lacatena at 04:13 AM on 1 July 2011Websites for Watching the Arctic Sea Ice Melt
130, Eric the Red, You're kidding, right? You need to wait for 26 years before you'll see enough evidence to support climate change theory? Except by then the cumulative change that you need to see to convince you is 1.3C, with more warming in the pipeline, and presumably more CO2 to be added to the atmosphere after that because our infrastructure will still be unchanged. So you are basically saying that we have to be committed to a very dangerous 2˚C of warming before you'll even admit that climate scientists have it right. How can you not label that as complete and total denial? As far as the middle of the road goes, I see no evidence of scientific inquiry on your part. I see clear evidence of you reading every single piece of evidence presented as just not enough in your opinion, so you have to wait until what might as well be the end of time until you're sure that anything is true. Sorry, Eric, but your position is completely unsupportable and irrational. You try to speak rationally and act like you are in the middle of the road, except outside of the window dressing of the calm, reasonable words themselves, your position is far, far, far from scientific. -
KR at 04:05 AM on 1 July 2011Uncertainty in Global Warming Science
Dikran - That's alright, I've had my posts deleted before. Although I hope it's the first time it's happened by accident! As to Pierrehumbert being hard going, that's OK. I read his recent Physics Today article, and don't have any illusions about him oversimplifying things. Time to take my neurons out for a few push-ups, anyway. -
dana1981 at 03:55 AM on 1 July 2011Lessons from Past Climate Predictions: Don Easterbrook
Yes, any projection which completely neglects physics the way Easterbrook has done can accurately be described as 'junk science'. -
les at 02:56 AM on 1 July 2011Lindzen Illusion #7: The Anti-Galileo
To coin the old phrse Eppur si calefacit -
Albatross at 02:52 AM on 1 July 2011Lessons from Past Climate Predictions: Don Easterbrook
Thanks Dana. I suspected as much, but 0.3 C?! Good grief. Now figure this. He claims climate sensitivity is low, well practically non-existent in fact. But then look at the huge decadal-scale perturbations in global temperatures in his graphs that he attributes to solar and, worse yet, internal climate modes. Said perturbations are greater in amplitude (> ~0.5 C) than anything observed in the global SAT record since 1850. Yet at the same time he would have us believe that the climate system is insensitive to selected external forcings such as CO2. This is junk science (by deniers of AGW) at its best. -
Tom Curtis at 02:47 AM on 1 July 20112010 - 2011: Earth's most extreme weather since 1816?
Eric the Red, if you want to actually run a correlation between the precipitation data and the PDO index, and also with Crutem, or hadCRUT3v by all means. As it stands, I do not think the correlation will be significantly better, if at all. Given that, there is a clear causal connection between high temperatures and high precipitation. In contrast, it is not even clear that the PDO is a genuine oscilation distinct from ENSO effects, and you have no explanatory path from PDO to higher precipitation. More importantly, the correlations you are trying to find certainly do not apply in the SH, so you are then left trying to find to distinct and non-compatible explanations, one for the NH and one for the SH. If you think there is something in it, do the leg work. If not, then there is nothing to discuss. -
Bob Lacatena at 02:45 AM on 1 July 2011Ocean acidification: Coming soon
I can't tell from the list of post titles, but I'd love to see an "Ocean Carbon Cycle" diagram, similar to the carbon cycle diagrams we've all seen, but focused on the forms (molecules) and mechanisms (weathering, atmospheric absorption, dissolution or recombination, etc.) that occur within the system. Obviously, the numbers may not exist to show how much each component contributes, but just a designation of what is there, if not how much, would be useful. -
Patrick 027 at 02:43 AM on 1 July 2011The Planetary Greenhouse Engine Revisited
It is still incorrect to refere to the top of the troposphere and mesosphere as radiating layers; aside from net radiant heating or cooling or gross emission and absorption or net fluxes among layers, for Earth, much radiation escaping to space is emitted from within the troposphere, some comes from the stratosphere, very very little comes from above that; more comes from the warmer layer around the stratopause than from the mesopause region, and more would come from a warmer layer than a cooler layer of the same thickness except for variations in height, line broadenning and line strength (actually I think line strength may tend to increase with temperature but I'm not sure), and composition (ozone in particular in the upper atmosphere). -
Dikran Marsupial at 02:37 AM on 1 July 2011Uncertainty in Global Warming Science
KR wrote: "Dikran - Well said, and thanks for the Pierrehumbert book reference; I've just ordered it." Sorry KR, hit the wrong button, mea maxima culpa! It is indeed an excellent book, but rather hard going. I'd recommend it to anyone wanting to look a bit more deeply into the physics, although a recommendation from one of the physicists here would carry more weight! -
Eric the Red at 02:16 AM on 1 July 20112010 - 2011: Earth's most extreme weather since 1816?
Tom, I think you are looking too much at each individual value. If you smooth the values over 5 years, then the scatter dissipates, and a good correlation is evident. I did not say it was perfect, but it does show possibilities. I agree that the period from 1960-1970 does not correlate as well. The PDO was negative for most of the decade, while the rainfall fluctuation, but was only low for three years; 1963,5, & 8. For most of the 80s, the PDO index was possitive, and the rainfall was low. Rainfall was only high for two years, which corresponded to a negative PDO around 1990. This was one of the better periods of agreement. Since 2000, the PDO has bounced from negative to positive, and back to negative. Rainfall started high, fell, and rose again, but you could argue that timing was not the best. Also, look at the periods of highest rainfall; mid 50s, mid 70s and ~2000. During these periods, the PDO was the most negative. During the periods of lowest rainfall; early 1930s, early 40s, mid 80s, and early 90s, the PDO was most positive. -
dana1981 at 02:01 AM on 1 July 2011Lessons from Past Climate Predictions: Don Easterbrook
Albatross - from these projections it's unclear what Easterbrook thinks about climate sensitivity, since he completely neglects CO2. Of course, the fact that he neglects CO2 does suggest that he thinks climate sensitivity to it must be near zero. From dhogaza's link, if Easterbrook thinks an increase from 300 to 380 ppm should have caused 0.1°C warming, he thinks sensitivity to doubled CO2 is 0.3°C. This is indeed ludicrously low, even more extreme than Lindzen, Spencer, and Christy. -
Nicholas Berini at 01:51 AM on 1 July 2011Throwing Down The Gauntlet
Another element to taking personal action is that when society finally does catch up to the true costs of carbon you will be more prepared emotionally and economically - ie your life will not have to change drastically to move away from carbon-intensive activities/habits. -
Albatross at 01:34 AM on 1 July 2011Lessons from Past Climate Predictions: Don Easterbrook
Dhogaza @45, Thanks for that link. Oh dear, that document does not do Easterbrook any credit at all. He even invokes the "in the past temperature lead CO2 so there is nothing to worry about" myth, the "it has cooled since 1998" myth, the "CO2 comprises a tiny fraction of the atmosphere so is not a big player" myth. Easterbrook also makes this claim: "The greenhouse effect of CO2 decreases exponentially, so the rise in atmospheric CO2 from about 0.030% in 1950 to .038% in 2008 could have caused warming of only about 0.1° C." Maybe Dana will chime in at this point. Dana? -
Dikran Marsupial at 01:30 AM on 1 July 2011Uncertainty in Global Warming Science
Ken, the IPCC discuss the "instantaneous" forcings as that is the presentation that is most easily understood. Now if you want to see what happens when they are integrated, look at the output of a GCM, that is exactly what they are designed to do. I have pointed out that S-B outbound IR increases, and yes you have mentioned them, however what you have not done is demonstrate that the increase in outbound IR does not equilibriate fast enough that any uncertainty in absolute TSI from pre-industrial equilibrium would not by now be of negligible significance. Now if you don't like GCMs, then your remaining option would be to contruct a simple idealised model of the climate (such as those described in the first few chapters of Ray Pierrehumbert's book). If you could construct such a model, where the parameters were physically plausible and broadly consistent with observations, then we would have something we could work on. Until then, you are essentially just arm waving, you may have a point, but you need to do some science to back it up. Note the IPCC reports were written by leading experts on this stuff; I hope it has ocurred to you that there may be some physics that they understand rather better than you do, and that you might be very wrong. -
GreenCooling at 01:15 AM on 1 July 2011Ocean acidification: Coming soon
Fantastic to hear you are looking at the OA issue, very keen to gain a greater understanding of this truly alarming evidence of AGW. I work on reducing the contribution of refrigerant gases to climate change, and am extremely concerned about the new generation of low GWP "HFO's" such as R1234yf, that are being heavily promoted by fluorochemical companies to maintain their market share in the face of impending regulatory and market mechanisms to phase out high GWP HFC's and competition from genuinely climate friendly natural refrigerants (Hydrocarbons, CO2, NH3). The HFO's only have low GWP due to their extremely short atmospheric lifetimes, and degrade into TFA, trifluoroacetic acid, which has raised some concerns in the literature about acute ecotoxicity developing in inland waterways. My query is whether, if the fluorolobby get their way and succeed in achieving the massive sales volumes of these new gases they are planning, there is a risk that this new global experiment with putting fluorinated gases into the atmosphere may contribute significantly to ocean acidification from another source, at a time when introducing more acids into the water cycle might not be a very clever idea? I think there is a need for more research on this issue, and if it is to come in time to influence policymakers who currently believe HFO's are a solution to the HFC problem, the need is rather urgent, but any insights from experts in OA would be of great interest at this year's Montreal Protocol discussions.
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