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ScaredAmoeba at 07:18 AM on 25 June 2011Rogues or respectable? How climate change sceptics spread doubt and denial
I omitted mined quotations. I understand that in many cases these are silently edited-out later. -
Patrick 027 at 07:14 AM on 25 June 2011The Planetary Greenhouse Engine Revisited
re my 32 even if the inversion runs all the way through the stratosphere and is sufficiently strong, etc, the downward LW radiation would gradually go from zero to a peak before coming down. Provided optical thickness has no complete spatial gaps (z varies continuously over optical thickness when the later is used as a vertical coordinate), then for any inversion which reaches all the way down to the level being considered, the downward LW flux will saturate at a value that is less than what it is some point before, in a progression toward larger optical thickness. Earth's lower stratosphere is in some places roughly isothermal; the lapse rate is negative down to, or to near, the tropopause in lower latitudes, while in winter polar regions the lower stratosphere can have a small positive lapse rate. (PS what I refer to as the lower stratosphere can/may be as much as 90 % or more of the mass of the stratosphere.) -
Paul D at 07:13 AM on 25 June 2011A Detailed Look at Renewable Baseload Energy
grayman: "But being in farm and ranch country, that biomas is better used as feed stuffs than elec. generation especially in times of drought, and i suspect it is the same around the world for farms and ranches." You have to back that up with figures. What is the efficiency of converting the energy in biomass into meat and then into energy used by the human body? Compared to converting biomass (via incineration or anaerobic digestion) into energy (electricity or heating) for general use? -
Paul D at 07:07 AM on 25 June 2011A Detailed Look at Renewable Baseload Energy
grayman: "Hydro electric power is a great source buti am unsure about Norway use of it, and if i remember correctly they import alot from the danes and sweden." So what?? I'm not actually sure that is true, they are pretty self sufficient and export most of their gas to the UK and Europe. Even if it were correct, borders aren't a problem are they?? There is no specific requirement for a nation (whose boundaries is a figment of the human imagination) to be self sufficient in energy, if everyone has been happy to import and export fossil fuels, I hardly see that import and export of electricity to be a problem. Electricity isn't some magically different energy commodity. -
ScaredAmoeba at 07:06 AM on 25 June 2011Rogues or respectable? How climate change sceptics spread doubt and denial
“The very first step should be for climate scientists to make a conscious effort to read some of the documentation appearing in the more respectable sceptic weblogs,” Are there any 'respectable sceptic weblogs'? I honestly can't think of one. Every single one I've visited was clogged with numerous examples of bogus claims; malicious accusations; venomous innuendo; pseudo-science; conspiracy theories and unsubstantiated false accusations against respectable scientists. My understanding is that's neither what's 'respectable', nor remotely 'scepticism'. Should anyone not believe me: ...I had no idea that is what these guys are doing. I am absolutely pissed off at this kind of junk science. This wouldn’t pass the smell test in any field except climatology and it only passes here because there is motive....They would almost want bad data to prove global warming was caused by man. We might as well roll dice and run it through the algorithm.... Follow the link if you dare, you have been warned.Response:[DB] Please refrain from linking to...websites such as that one. At SkS the focus is on the science within an atmosphere of civility.
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Albatross at 07:05 AM on 25 June 2011Linking Extreme Weather and Global Warming
Camburn @ 212, You say "The trend changed and the lake was virtually a dry basin in the 30's and very small till the 90's. It is once again filling to the point that it was in during the 1860's-70's. Once again, not extreme but causing a lot of economic distress." No. According to this fact sheet, Devil's Lake is at its highest levels since at least 1865. In fact, it has only been higher than current levels three times in the last 4000 years. So recent levels, while not unprecedented, are certainly extreme.
Source]
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Paul D at 07:01 AM on 25 June 2011A Detailed Look at Renewable Baseload Energy
grayman - you don't solve all the problems of the future by writing precise solutions clearly and fully worked out today. That never has happened. You start working on the problems and gradually build up, with engineers solving problems as they go along. The current systems weren't dreamt up in a few years and clearly worked out. We have large power stations, the grid and all the equipment that makes it work, all of which developed incremently, step by step. -
Eric the Red at 06:53 AM on 25 June 2011Linking Extreme Weather and Global Warming
JMurphy, None whatsoever. Snowfall is greatest at temperatures nearest freezing. As you deviate from there, snowfall decreases (drier when colder, changing to rain when warmer). Since most of the planet is above freezing most of the year, warmer temperatures will create a greater divergence from freezing, hence less snow. -
grayman at 06:41 AM on 25 June 2011A Detailed Look at Renewable Baseload Energy
4) biomass is just putting more CO2 in the air and using as you describe in the post crop and plantation forest residue is not a year round solution unless you have yr. round crops providing enough product to burn which IMHO i do not see happening, wish i were wrong on this. But being in farm and ranch country, that biomas is better used as feed stuffs than elec. generation especially in times of drought, and i suspect it is the same around the world for farms and ranches. Geothermal seems to be the best all around for clean energy production, but what of problems of the fact of removing all this heat form these areas in ground, unintended concequences perhaps. Hydro electric power is a great source buti am unsure about Norway use of it, and if i remember correctly they import alot from the danes and sweden. Much less the problem of frezzeing weather up there , yes i have been to norway a couple of times, beautiful counrty and people. I suppose it gets down to the problem for me anyways is that so many study of this and that and not enough of studys of the doing part if this makes any since. Sorry the heat outside has me feeling a little wierd. -
Albatross at 06:30 AM on 25 June 2011Sea Level Hockey Stick
BP @96, Yes, extraction has not been constant. But your entire premise rests on your presumption that the water extraction along the coastal plain has had a marked impact on the study sites. The data suggest otherwise, from the RC post: "These data are valid for North Carolina, where they are also in agreement with a local tide gauge (Fig. 2 in the paper). But they also agree with another proxy data set from Massachusetts."
Sea level evolution in North Carolina from proxy data (blue curve with uncertainty range). Local land subsidence is already removed. The green curve shows a reconstruction based on tide gauges from around the world (Jevrejeva et al. 2006, 2008). The red curve shows results from a simple model connecting global temperature with sea level.
You said earlier "Recent acceleration of subsidence on the coastal plain is most likely due to groundwater depletion (sediment compactification occurs as pressure in coastal groundwater table is decreased by overexploitation). There is also a high local variability in this rate, because it depends on both nearby drilling history and structure of local layers at depth."
So you are arguing what ifs then. You also admit that impacts depend on the nearby drilling history. As shown in Fig B2 in the document you referred us to, there are no continuous borehole sites near the study sites, nor are there any observational wells.
At this point I would suggest that you go to RealClimate and engage the authors there with your hypotheses. And please do not offer up excuses why you might not do that. I for one am interested in what they say about your claims.
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grayman at 06:23 AM on 25 June 2011A Detailed Look at Renewable Baseload Energy
Paul D. Sorry, had to take my son to town, 3) being in the north atlantic region before, and the past few years weather has been brutal for wind turbines i.e. cuasing a lot of problems for them from freezing to out right breakage, much less maintenance and repair, brings up more problems than can be modeled. Per reply, yes cost is one thing but it does not seem to be a factor for them as they still burn these lights thru out the night, and sensors have fixed the street light problem, but IMO there is still to many period. These studies you qoute say that renewable energy can be done, but when will a study(s) be done on how. there seems to be many saying yes but none saying how to fix so many problems in the future. -
Djon at 06:10 AM on 25 June 2011Rogues or respectable? How climate change sceptics spread doubt and denial
Patrick, If you want to be taken seriously here, saying something is flawed isn't enough. You'll have to actually demonstrate that it's flawed by pointing out specific errors or shortcomings. Also, I think it's generally frowned on here to quote without attribution, as you did with the italicised paragraph. Even better, link to the original so people can easily check out the full context of your quote. -
Bibliovermis at 05:57 AM on 25 June 2011Rogues or respectable? How climate change sceptics spread doubt and denial
Patrick, Check out argument #120, "Naomi Oreskes' study on consensus was flawed". An examination of the papers that critics claim refute the consensus are found to actually endorse the consensus or are review papers (eg - they don't offer any new research but merely review other papers). This led the original critic Benny Peiser to retract his criticism of Oreskes' study. -
JMurphy at 05:55 AM on 25 June 2011Linking Extreme Weather and Global Warming
"Overall, AGW predicts greater precipitation, but not snow." "Colder temperatures tend to result in lower snowfall totals." So, Eric the Red, can you see the divergence between those two statements of yours ? -
KR at 05:43 AM on 25 June 2011Sea Level Hockey Stick
The objections to this paper on WUWT (Willis Eschenbach column) are primarily complaints that insufficient data was published along with the paper, in particular the look-up table of depth versus species ratios for the ~200 calibration samples, and that (unspecified) sections of the math were lacking to the point of not enabling proper review. I noted that establishing species ratios vs. depth is pretty standard practice in foraminifera studies, and asked whether they needed the paper to also contain multi-semester courses in GIA, foraminifera identification, tidal gauges, radioisotope dating, and perhaps a private tutor and a masseuse to help them through the material.../sarcasm I expect impolite responses... What's most interesting to me is that this paper was written by six authors, with Michael Mann as the fourth - contributing, but not the lead author - it's Kemp et al 2011. Yet the skeptic blogs are ranting about the "Mann" paper - he appears to be a favorite target for Ad hominem attacks. Logical fallacies, of course, but an easy target for that audience. -
Patrick Kelly at 05:41 AM on 25 June 2011Rogues or respectable? How climate change sceptics spread doubt and denial
In the interests of getting exposure to as many viewpoints as possible, I waded into Prof Entings offering. Alas! He proceeds to cite as his first authority Oreskes' discredited The Merchants of Doubt. Oreskes is a non scientific [ -Inflammatory & Ideology/Political Snipped- ).Merchants of Doubt is long on innuendo and short on evidence or compelling logic. It fits well with Mark Twain’s classic observation of about the gathering facts and then distorting them as the gatherer desires.
So with Oreskes being the cardinal point of reference, my motivation to read further disappeared as quickly as a proxy temperature record data set. Sorry Prof.Response:[DB] "my motivation to read further disappeared as quickly as a proxy temperature record data set"
Would that be what real skeptics do?
Please try to adhere more closely to the Comments Policy when formulating future comments. Thanks!
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Camburn at 05:30 AM on 25 June 2011Linking Extreme Weather and Global Warming
Albatross: I got in what I could get in. We had 3 inches of rain two days ago and are once again extremely wet. The long term forcast, which is fairly reliable as it is a result of La Nina is continued wet for another 6 weeks. Production in Canada, North Central US is going to be down in major crops. Not a good thing. The thread is about extreme events. While present conditions in my area are not what one would consider extreme, I will say that they are tiresome. We have a long term cycle of wet and dry. We have another 20 years of wet to live through, assuming the cycle is persistent. A good gauge of long term precip in the upper MidWest is Devils Lake. It was running out of the Tolna Coule in the 1860'-1870's. The trend changed and the lake was virtually a dry basin in the 30's and very small till the 90's. It is once again filling to the point that it was in during the 1860's-70's. Once again, not extreme but causing a lot of economic distress. -
Paul D at 05:26 AM on 25 June 2011A Detailed Look at Renewable Baseload Energy
Sure Chill fridge technology uses phase change material to keep cooling for 10 days without power: http://www.surechill.com/ Although having had a look at the vaccine fridge it is pretty bulky. I think they are working on an improved design for commercial/domestic applications. -
Berényi Péter at 05:25 AM on 25 June 2011Sea Level Hockey Stick
#96 Albatross at 02:27 AM on 25 June, 2011 So a constant correction was applied to all the data, and just as if a temperature sites has a systematic bias, that systematic bias/offset does not affect the trend. But groundwater extraction rate in the North Carolina Central Coastal Plain was not constant during the last two thousand years. From the USGS report: "As of 2004, large volumes of groundwater being pumped in the CCPCUA ([North Carolina] Central Coastal Plain Capacity Use Area) had affected groundwater levels and flow regimes (State of North Carolina, 2004) in the aquifers and confining units underlying the area. As the simulated groundwater flow budget analysis indicates, groundwater continues to be removed from storage in many of the hydrogeologic units, and groundwater level declines continue to occur. Until these reductions in groundwater storage are lowered or stopped, groundwater availability will continue to decline in this area." For example PSMSL station DUCK PIER OUTSIDE is not too far (less than 30 km) from Sand Point (where secular coastal land subsidence rate is said to be 1 mm/year). If you calculate rate of sea level change relative to the tide gauge station there between the end of 1992 and beginning of 2010, it turns out to be 4.86 mm/year. On the other hand satellite data at the same location and for the same time period show 1.16 mm/year. It means land subsidence rate at Duck Pier is 3.7 mm/year during the last two decades, almost four times the secular rate due to GIA alone. The additional 2.7 mm/year is probably caused by decreasing pressure in the groundwater table adjacent to the coast. And this (clearly anthropogenic, but local) phenomenon is a new one, caused by excessive drilling and pumping in the region (which, unlike fast increase in global atmospheric CO2, started in the late 19th century indeed). Is it obfuscation, really? Can we look forward to you writing up and submitting a formal rebuttal to the journal, or are you simply here to grandstand? You can't, it's not my job. There are guys who get a salary for that. And I am really surprised this issue has not come up in the peer review process. It is more than obvious. BTW, you are free to submit a letter to PNAS, I have no claims :) -
Eric (skeptic) at 05:24 AM on 25 June 2011Linking Extreme Weather and Global Warming
I was simply explaining why one river was breaking the record by five feet. Minot had 6.22 inches of precip in May versus normal of 3.91 but Jan-Apr were all below normal. Their river record is fairly isolated except for the Missouri downstream from the Ft Peck dam which just started releasing extra water in early June. The flood control releases must be considered when comparing old records to new ones. -
Paul D at 05:00 AM on 25 June 2011A Detailed Look at Renewable Baseload Energy
Re grayman@9 - the cost is a good incentive for reducing consumption :-) If you don't need lights on in the evening then you are wasting a lot of money by having them on. There is an issue of security (keeping the burglars away), light pollution etc. At least there is no excuse now for street lighting to be on during the day. I remember the old fashioned electromechanical timers used to get out of sync and lights would remain on during the day. These days light sensors have fixed that problem. -
grayman at 04:49 AM on 25 June 2011A Detailed Look at Renewable Baseload Energy
Hi Dana, Well written post, a few questions. 1) I am sure you have wondered as have i that the cities we live in, why all the lights on in buildings ETC. when not in use from private to govt., i find it a waste. How do we get this slowed or stopped, that would be a suffient start. Just looking at satilite picture of cities at night boggles the mind and i for one see it as a waste period. 2) How can a model accuratly portray the probrabilties of wind when weather models a barly able to do it 4-5 days out, as jetstream winds much less lower level winds are to variable in speed or predictablity? -
Paul D at 04:48 AM on 25 June 2011A Detailed Look at Renewable Baseload Energy
In the UK RLTec have developed a smart grid fridge which alters it's energy use depending on what power is being provided by the grid: http://www.rltec.com/ According to their latest press release they did a deal with Sainsburys to put the technology in 200 supermarkets. They have also developed a fridge with Indesit. I know another UK company are developing a fridge/freezer that can continue working for about a week without power. They're using a phase change material. The technology was originally developed for cooling vaccines in developing countries. -
Eric the Red at 04:45 AM on 25 June 2011Websites for Watching the Arctic Sea Ice Melt
JMurphy, I was looking for it in the Hansen report because michael stated that the report made such a claim, which resulted in the subsequent posts. michael, If you claim that all these effects are the result of rising temperature (resulting from a CO2 increase), then a reduction in temperature (CO2) will reverse all the effects. Which of these effects will not be reduced? We cannot undo a flood that already happened, but future flooding would be reduced. sky, The trend in maximum sea ice extent shows considerable linearity. The trend in minimum sea ice show more linearity than not, but may be skewed by the high value in 1996 and low value in 2007. It is entirely possible that it could be non-linear, or a shift in the linear trend starting in 1996. There are other possibility that exist with such a small dataset. Some people here seem to prefer the volume calculations over the area measurements. I have a differences of opinion on the topic which I will not pursue. Tom, Yes, it was an initial response to your post, which has been blown out of proportion, and should be put to rest. -
Albatross at 04:37 AM on 25 June 2011Linking Extreme Weather and Global Warming
Thanks Camburn. Have you managed to sow your seeds yet? -
Camburn at 04:35 AM on 25 June 2011Linking Extreme Weather and Global Warming
Albatros@206: We are in a global ag market with 3 grains being the main ones traded. Soybeans/Corn and Wheat. Brazil is a major player in Soy/corn.....Agentina soy/wheat. The US is a major player in all of them. Rainfall affects production in Brazil/Arg just as it does in the USA. All of this affects the world markets prices. That is how it affects my business. -
Paul D at 04:34 AM on 25 June 2011A Detailed Look at Renewable Baseload Energy
Norway is I believe almost totally hydro-electric which isn't practical for most nations/regions. Power generation is not the only issue as Okatiniko says. We are talking about system design from generator to home or factory. The load(s) have to be balanced with the power source(s) otherwise the grid/mains frequency starts drifting. In fact one of the key ways that a smart grid would work is buy monitoring the frequency so that intelligent appliances can alter their use of energy. -
Eric the Red at 04:24 AM on 25 June 2011Linking Extreme Weather and Global Warming
JMurphy, Of course, we in the North know that adage well. A few notes on your post. Heavier snowstorms occurred in wetter winters sounds self-evident, and has no relation to temperature. The Changnon study was restricted to heavy snowstorms. Their graph of snowstorms (which may or may not correlate with seasonal snowfall) shows that snowstorms were lowest in the three decades from 1920-1950, and highest in the 1910s, and 1960-1980. Roughly corresponding to the high and low temperature decades (the exception being the 1990s). The heaviest snowfall occur when the temperature hovers around freezing. Colder temperatures tend to result in lower snowfall totals. The report did not mention total seasonal snowfall. -
Tom Curtis at 04:06 AM on 25 June 2011Websites for Watching the Arctic Sea Ice Melt
Eric (Skeptic) @102, David Archer has studied this issue extensively. He shows that if we release 2000 Gigtonnes of CO2 into the atmosphere, then in a thousand years, atmospheric concentrations will still be elevated by 29% of that value, and by 14% after 10,000 years. He also shows an interesting graph correlating global temperatures with sea levels from geological records:
(As adapted here)
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Bibliovermis at 04:05 AM on 25 June 2011Linking Extreme Weather and Global Warming
My guess would be that is where his planting stock comes in from. -
actually thoughtful at 03:52 AM on 25 June 2011A Detailed Look at Renewable Baseload Energy
Okatiniko - You say that Norway already has 100% renewable energy, then you say computer simulations that say you can run a country on 100% renewable are wrong. Can you clarify your point? -
Albatross at 03:51 AM on 25 June 2011Linking Extreme Weather and Global Warming
Camburn, A long time ago you stated in a discussion with me that: "I am most interested in Argentina/Brazil as weather patterns in that area directly affect my business." With you being a farmer in N. Dakota, how does rainfall in Argentina/Brazil directly affect your business? -
SouthWing at 03:51 AM on 25 June 2011Rogues or respectable? How climate change sceptics spread doubt and denial
“The very first step should be for climate scientists to make a conscious effort to read some of the documentation appearing in the more respectable sceptic weblogs,” he argued. Hmm..."respectable sceptic weblogs"... Nope, sorry: can't think of a single one. -
Composer99 at 03:44 AM on 25 June 2011A Detailed Look at Renewable Baseload Energy
okatiniko: {citations needed} -
rocco at 03:43 AM on 25 June 2011A Detailed Look at Renewable Baseload Energy
okatiniko: Your contribution here will be much more valuable if you actually bother to read your posts and make sure they make sense before you hit the submit button. -
Tom Curtis at 03:42 AM on 25 June 2011Websites for Watching the Arctic Sea Ice Melt
michael sweet @105, given sufficient low entropy energy, in principle everything is reversible (except perhaps plate tectonics). We could even resurrect the dinosaurs in principle, although it would probably take fifty years research to develop the correct techniques. We would certainly be able to resurrect all of the many species expected to go extinct over the next century - if we where prepared to devote enough resources to it. Should we desire, we could even spray sulfates in the upper troposphere above greenland, and "crop dust" the surface with fresh water to recreate the ice sheet and glaciers. What we can't do is reverse anything except the smallest changes cheaply. We can't reverse anything significant except at a far greater cost than the cost of preserving it in the first place. And what is more, given the likely impacts of BAU, in fifty years we won't have the spare resources to even think about reversing anything. Contrary to Eric's claim that he was responding to you when he made his comment about reversibility, it was actually a response to my claim that effective action had a used by date of 2020 @86 (see his 87). As such, it was an empty rhetorical sally to divert attention from my point and should be allowed to die a quiet death. -
Composer99 at 03:41 AM on 25 June 2011Rogues or respectable? How climate change sceptics spread doubt and denial
The "Galieo Gambit" in action. What climate science "skeptics" (along with anyone else who attempts to score rhetorical points with this gambit) forget is that it is not enough to espouse a position contrary to the consensus of experts. One must also be right. The contrarians have manifestly failed in this latter regard. Indeed, they are not even persecuted the way Galileo was (that fate is, it seems, reserved for climate scientists). -
Albatross at 03:25 AM on 25 June 2011Linking Extreme Weather and Global Warming
JMurphy You are quite right about what constitutes "precipitation". -
Albatross at 03:25 AM on 25 June 2011Linking Extreme Weather and Global Warming
EricS and Camburn, While management of river flows and dams is obviously critical in these situations and sometimes bad decisions are made. Have either one of you paused to actually consider why we have all this water on the ground to manage in the first place? This cannot mostly or all be blamed on officials guys, the primary reason for this situation is that the Northern Great Plains have been receiving record-breaking rains at a time when the soils are saturated, dams are full and rivers swollen. But yes, let us ignore those very real and critical factors and take our anger and frustration out on officials. And both of you seem to be forgetting that rivers are breaking previous records on the order of metres. No, no, nothing unusual going on here at all. I have stated before that people in denial about AGW can and will be knee deep in water and still be claiming that 1) It is OK, this happens all the time, nothing unusual here, or 2) This is happening because of something else unrelated to AGW. With all that said, Camburn, keep safe. PS: Camburn earlier I gave you the Chagnon details to look up trends in thunderstorms and associated phenomena, but you seem to have used it to go on a very different tack. -
okatiniko at 03:24 AM on 25 June 2011A Detailed Look at Renewable Baseload Energy
Norway has already a 100 % renewable electricity , and other countries such as Iceland as well, and other such as France have an almost carbon free nuclear power. The issue is not only power generation, but power USE. Computer simulations may prove that it is possible to use only electricity and biomass - reality proves that computer simulations are wrong. -
JMurphy at 03:19 AM on 25 June 2011Websites for Watching the Arctic Sea Ice Melt
Eric the Red wrote : "I find no one in the Hansen report were he says that the amount of CO2 added to the atmosphere today is enough to raise sea levels 5m." Why were you looking for such a scenario in that report ? -
actually thoughtful at 03:08 AM on 25 June 2011A Detailed Look at Renewable Baseload Energy
I applaud Skeptical Science's work on debunking these myths that state, in essence, "there is nothing we can do about it anyway". There is, and many, many individuals and companies are taking steps on their own initiative, in light of the global failure of governments to respond. -
Albatross at 03:07 AM on 25 June 2011Websites for Watching the Arctic Sea Ice Melt
EricR @96, "The IPCC predicted that it would take a 5.5C temperature rise to melt Greenland, and it would take several centuries. Recent studies show that the melt rate is significantly less." That statement is demonstrably wrong. Your biased interpretation of the papers (which you don't seem to really understand) have been addressed by Michael and Skywatcher, and you did not recognize your error, ignored their insights and just tried to re-frame your argument and shift the goal posts @100. Doing so is incredibly ungrateful, people are trying to help you understand this better, but you appear to have too many mental hurdles/blocks (and no I am not saying you are dim or anything like that) in the way I doubt you even followed the link to Tamino's statistical analysis of Arctic sea-ice volume. Monthly Arctic sea-ice volume anomalies:
September Arctic sea-ice volume anomalies with quadratic fit:
Source]
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michael sweet at 02:38 AM on 25 June 2011Websites for Watching the Arctic Sea Ice Melt
Eric, What about my questions about reversibility here?? You have chosen one of my comments and ignored the rest. You claimed that nothing is irreversible. What will reverse the flooding, drought, fires and ocean acidification that already exist? Your claim that all is reversible is not supported by showing that it is not yet known how much sea level will rise in the next few decades. It may just as well be true that sea level will rise more than 2 meters by 2100 as that it will be less than 1 meter, uncertainty cuts both ways. Your choice of only the most optimistic models is unlikely to hold up. -
Albatross at 02:36 AM on 25 June 2011Sea Level Hockey Stick
BP @94, "Anyway, this GIA thing only gives a -0.3 mm/year contribution to sea level rise." Well there you have it folks, BP agrees with the University of Colorado, and refutes the ridiculous assertions being made here. -
Albatross at 02:27 AM on 25 June 2011Sea Level Hockey Stick
BP, I commend your obfuscation efforts @80. On the surface of it, and ignoring your unsubstantiated hypotheses and musings, you may (or may not) have a out about the GIA correction. Can we look forward to you writing up and submitting a formal rebuttal to the journal, or are you simply here to grandstand? But before that, perhaps we should show what they actually say in the paper: "A constant rate of subsidence (with no error) was subtracted from the Sand Point (1.0 mm/y) and Tump Point (0.9 mm/y) records. These rates were estimated from a US Atlantic coast database of late Holocene (last 2000 y) sea-level index points (13, 15). Use of a constant rate is appropriate for this time period given Earth’s rate of visco-elastic response (14). The resulting records are termed “GIA-adjusted,” expressed relative to mean sea level from AD 1400–1800 and visually summarized by an envelope (Fig. 2C)." So a constant correction was applied to all the data, and just as if a temperature sites has a systematic bias, that systematic bias/offset does not affect the trend.Moderator Response: [Dikran Marsupial] Please can we all dial back the tone of the discussion a notch or two, and keep things on a constructive a level as possible. -
pbjamm at 02:26 AM on 25 June 2011Sea Level Hockey Stick
Camburn@74 It is right there in the OP: "IPCC AR4 showed that local sea-level trends differed by up to 2 mm/y from the global mean over AD 1955–2003, which implies deviations of up to ±10 cm at some locations (but ±5 cm along most coastlines) as the sum of forced and unforced effects. This analysis suggests that our data can be expected to track global mean sea level within about ±10 cm over the past two millennia, within the uncertainty band shown for our analysis." So if I am understanding it correctly, this regional proxy is average when compared to global proxies. Not everyone can be a unique snowflake! On the Bell Curve someone has to be average. -
Berényi Péter at 02:13 AM on 25 June 2011Sea Level Hockey Stick
The only process that has a measurable effect on ocean basin volume is GIA (Glacial Isostatic Adjustment). Currently volume of ocean basins is increasing at a 100 km3/year rate, because vast continental areas that were once covered with miles of ice, having got rid of this weight, started rising. It can only happen if mantle material (which behaves as a high viscosity fluid) is sucked in from below the oceans to support rising rock. That is, ocean basins next to previous ice sheets (like the Laurentide and Fennoscandian one) are getting progressively deeper. All other processes like plate tectonics or sedimentation operate on much longer time scales and their contribution is negligible to millennial rates of ocean basin volume change. Anyway, this GIA thing only gives a -0.3 mm/year contribution to sea level rise. As for ocean water volume changes, relative sea level measurements at continental margins (tide gauges) are not representative, because continental margins themselves are sinking on average. There are two reasons for that. One is still GIA, because sea level is some 120-140 m higher now than it was twenty thousand years ago. This additional weight of seawater is slowly pushing continental margins down (relative to the true geoid). The other one is ground water depletion which (through decreasing pressure in water table) induces sinking of sedimental layers in many coastal regions. Therefore part of sea level rise as measured by tide gauges is in fact (coastal) land level decrease. Volume of sea water can change in two ways. One is steric when water mass is unchanged and only its volume changes due to decreasing (or increasing) density, mainly because of changes in heat content. In this respect sea level behaves as a thermometer. Not a terribly good one though, because volumetric thermal expansion coefficient of seawater depends heavily on both temperature and pressure, so the addition of the same amount of heat can produce quite different sea level changes depending on which part of the ocean absorbed it. As volumetric thermal expansion coefficient is increasing with both temperature and pressure, while water temperature decreases with depth, there is a layer at about 1000 m below the surface where absorption of heat has the least effect on sea level. Expansion due to the same amount of heat absorbed increases both below and above this level (the former because of increasing pressure, the latter because of increasing temperature). The other way to change sea water volume is to change its mass, that is, to add some more water to the oceans or subtract it from them (and store it elsewhere). The main processes here is melting of land based ice (or snow accumulation), water storage in reservoirs (negative contribution) and groundwater depletion. These processes do not have much effect on heat content of the climate system. The last two has simply none, while melting ice uses almost a hundred times less heat to produce the same sea level change as (steric effect of) heat absorption by water. ( -Snip- )Response:[DB] Off-topic unsupported conclusions snipped.
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Albatross at 02:08 AM on 25 June 2011Sea Level Hockey Stick
"When dot-cloud radar scanners can penetrate 3700m of seawater and measure the bottom to an accuracy of 0.1mm, we could determine if the bathtub is growing or shrinking in volume. If the bottom was rising 1-2mm per year - there is your SLR." Surely they jest? What a lovely red herring. Occam's razor applies here, and some would rather have us debate how many angels can dance on a pin head, rather than face the fact that the global sea levels are rising in step with increasing temperatures as they have in the past (and here I mean over statistically significant periods of time). This paper has obviously causing "skeptics" and those in denial about AGW some cognitive dissonance and their posts here show that. Posts such as the one I quoted above are trolling and baiting, and nothing to so with the paper being discussed. It is also a perfect example of how someone in clearly denial can rationlize what they so dearly wish to believe. That is not science either. They are also examples of fabricating doubt, confusion and exaggerating uncertainty, claiming that "we do not know everything so we know nothing" all tricks routinely plied by the "skeptic" and denialist misinformation machine. Can we please get back on track folks. -
skywatcher at 02:07 AM on 25 June 2011Websites for Watching the Arctic Sea Ice Melt
Eric, is the trend in sea ice volume or in minimum sea ice extent linear or nonlinear? And please do not insult everyone's intelligence by suggesting that the trends are based on 'one or two points'! These things can and indeed have been assessed properly, and we do not need to rely on your 'anticipation' to evaluate the shape of the current trend.
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