gmoran
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Posts posted by gmoran
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Are you saying that it's IMPOSSIBLE to predict changes in global temperature a priori?
Firstly, what we are talking about are skilful predictions; if I predict that the sun will still be functioning next year, then I'd probably be right, but it isn't particularly skilful.
From a pure commonsense perspective, and a scientific one as well, it is obvious that future climate states cannot be skilfully predicted: climate system is non-linear; climate patterns (PDO, AMO, ENSO, AO) are poorly understood; future solar irradiance cannot be predicted; future volcanic stratospheric eruptions cannot be predicted - hence future climate cannot be predicted. Climate modellers are not attempting to predict future climate, but future boundary conditions given changes in forcing. Therefore yes, it is impossible to predict future climate, including GMST, using our knowledge of the climate system.
It is however possible to make naive predictions, e.g. the long term warming trend is .7'C per century, and it would be a reasonable bet that this would continue (however it is far from certain). As an example, if at the start of the 21C you were to predict the rate of change for the next decade using the naive method (.07'/D), you would have done far better than the GCM method (.2'/D), the actual change (Hadcrut3 dataset for the 120 months to Nov 2009) was .04'/D.
I agree with you, that 'local' climate is impossible to predict, but global temperature-prediction should be a lot easier to compute...That said, I'm not claiming that any particular prediction is right (or wrong). I can't possibly know that...
Don't you think this is an interesting point? If you take the synoptic definition of climate, then any prediction of future climate must involve skilful predictions of regional climate. Yet you think this is impossible to predict (a concept that this paper agrees with Koutsoyiannis et al 2008)? Why do you think predicting future global climate, using a synoptic model or a GCM, should be any easier?
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Long-range climate-predictions may indeed turn out to be wrong; they are 'scientific' afterall. But unfortunately, for one to accurately state such an opinion as 'fact' 30 years' in advance, one would have to have clairvoyant abilities!
I'll refer you to climate scientist and modeller Gavin Schmidt of NASA GISS: "there is so much unforced variability in the system which we can’t predict — the chaotic component of the climate system — which is not predictable beyond two weeks, even theoretically.", interview available here: Gavin Schmidt Interview. This is what I mean when I say it is physically impossible to predict future climate; and is subtly different to whether GCM's can skilfully project future boundary conditions in response to a forcing - though so far they do not appear to be skilfull in even this regard.
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What ticks a lot of people off, me included, is that the MetOffice have been putting out these annual and seasonal forecasts for some ten years now, and they really seem nothing more than a propaganda exercise to prove: AGW is occurring, and; climate predictions have some value. I think for a good proportion of this time the Meto have been helped by a warming trend, so they were (most of the time) backing the form horse. However since the mid noughties (globally) and from 2007 in the UK, things have changed, forecasting warmth has no longer provided such good dividends and the Meto have been caught out. GOOD. It is physically impossible to predict skilfully beyond what the current synoptics and teleconnections allow.
As far as these forecasts: they should stop with annual projects of GMST - GMST is highly correlated data, so naive forecasts are not particularly difficult, and proclaiming that GMST will be X above the anomaly is not skilful, or significant (a situation the Meto constantly misuse) and is merely propaganda; secondly seasonal forecasts are fine but should concentrate on what the synoptics show when the forecast is made, and should only extend as far forward as they allow - something akin to GPs forecasts would be useful.
Finally the Meto should stop with the propaganda. They constantly make announcements that this year will be in the top 10 warmest years as if this is proof of AGW; they did it at Copenhagen Meto Copenhagen Announcement - but this is not as significant as they imply, because GMST is highly correlated, if climate is plateauing, or dipping GMST would still be high. Their director untruthfully stated on a BBC news show that they had predicted the levelling off of temperatures in the noughties Meto Director On BBC news. How many times have you heard that medium term predictions are difficult, but long range predictions of climate are accurate. Sorry this is rubbish, it is impossible to predict the future state of the climate beyond the current synoptics - what GCM's do is to try to determine the differing boundary conditions when different forcings are applied, but they have not yet proven to be particularly skilful in this endeavour (hindcasting demonstrates basic competency but not skill). I think the Meto would benefit if they split out their climate group.
In summary I think the Meto are the author of their own misfortune, and I have no sympathy for them.
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I know what you mean, but then I suppose it's also possible to say that we, at some point, reached a tipping point, whereupon such synoptics became nigh-on impossible to achieve. Speculation perhaps, but it would explain what was quite a sudden change.
While there might be future "tipping points" waiting for us if global temperatures start rising again; there certainly have not been any "tipping points" associated with the current warming phase(1977 - ) or the long term warming trend (17?? - ). What is very likely however is that there has been a change in synoptics affecting the UK. Likely causes are ocean circulation cycles (any opinions on this?). If so the synoptics could (are likely to?) flip back.
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Firstly, it's "only" the CET; that it might be affected one way or the other by GW seems to me, to be neither here nor there. Surely GW is a measure of the average of everywhere and not some arbitrary region of England? It is conceivable that England might be in a area that might be expected to cool, it might be expected to warm, or, indeed, it might be expected to fluctuate wildly increasing both the floors and ceilings of temperature bounds. Who's to know, really?
In my reply to Reef I mentioned that averages hide details. What you are posting here is somewhat related: what should we expect the CET to do under GW; what is the significance of global mean averages? I understand that one of the areas climate modelers are keen to improve is the regional performance of GCM's! How meaningful are GCM projections of GMST, if regional projections are known to be weaker?
At any rate, the point raised is a good one, CET can go up or down, and have no significance to GW whatsoever; the UK must be a poor marker for GW being an island in the north east of the Atlantic ocean.
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To be fair to SF though, in that paragraph he doesnt specifically say a sub-3C month is impossible, but rather its extremely unlikely to happen. He's also spot on the money when talking about how cold isnt as prolonged and potent as it used to be.
There were similar mutterings at the end of April 2006 when the 12 month running mean hit 10.03C. It was the lowest it had been since 2001 and some people were certain it heralded a new trend. What actually happened though, was we quickly shot up to the highest value ever, peaking at 11.63C exactly a year later.
In reality, you could only so far really call the current downward trend a mere correction to the excessive warmth that occured a year or so before. Bare in mind we only passed the low point reached in April 2006 at the end of December 2008:
The graph there includes January at 3.2C (estimated). As you can see, while we're lower than any point after March 1997, all it shows at the moment is that we're still half a degree or so milder than then, as like now, there was a sharp rise followed by an equally sharp drop. For a notable drop suggesting a cooldown, we need to be looking at a trough as least as deep as the 1997, followed by any further high points being less than perhaps 10.50C. The main reason for this is that even in a static climate, you'll always get large variations either side of the mean.
So at present, it merely is a blip. It would have to continue for a long time before we can even suggest it might be cooling or indeed, even remaining static.
The graph is very interesting: the trend looks slight, and given the large amount of variability I'd guess not particularly significant. What is the trend, what's the standard deviation, and do any of the data points breach the 95% confidence intervals? It is obvious that British weather patterns have changed significantly since the 1960s, but annual mean averages and rolling 12 month averages will probably hide some of the information.
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How can that possibly be true?
It's a case of cherry picking: looking for a pattern in data and then attaching undue significance ( http://en.wikipedia.org/wiki/Cherry_picking ). A calendar month is a sample period uncorrelated to the data you are attempting to attach significance to, it is not biased.
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A months cold is a months cold whichever way you dress it up. What difference does the start and end day make?! :lol: Apart from satisfying the meteorological annuls of course. But it doesn't somehow make the climate warmer than it is because the dates don't conveniently match a calendar month!
Lets wait till the end of the month and the whole matter should be put to bed anyway regarding the point you are trying to make. But tbh I am rather bemused by the fixation and significance of this 3c winter CET thing. IMO it is pointless trying to place limits/benchmarks all the time and then moving them around once they are subsequently breached to try and keep a certain POV alive. We have had this with the annual rolling CET, but the script wasn't followed, and now it is happening with monthly winter CET's.
I don't think that this sub 3c CET is that significant - only in the minds of those who feel it is so hard for it to be breeched in the UK for some reason. Still, only 3 weeks to go and you will all know the outcome for this month I guess. But it will happen at some stage anyway.
In summary I wasn't actually trying to illustrate how cold it has been at all - merely that some people are speculating about the unlikeliness of something that has already happened under a differing range of datelines!
One of the problems with looking for statistical trends is cherry picking, finding data that suits your model and then attaching significance to it in retrospect. Using calendar months prevents that, such that a calendar month of sub 3'C has more statistical significance than finding 31 consecutive days that are sub 3'C.
Since 1860 we have been able to observe a long term global mean surface warming trend of .08'C per decade; since approx 1975 the warming trend is .16'C per decade. The interesting question at this time is whether the shorter term warming trend since the 1970's has now come to an end, and we can expect some cooling or at least some stasis. In the UK it may mean that synoptics since the early 1990's that have tended to preclude cold and snowy winters are now changing. Answers to these questions may take some years to become apparent.
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Do the Metoffice really need to delay the December temperature to disguise a cold month in a warming climate, when it's happening around the world regardless of the final figure? The UK is a small area, the majority of the world had a warm December and very warm year.
I'm not sure where you are getting your data here? HADCRUT3 clearly shows that 2008 GMST continues the cooling trend (.321'C to Nov) since 2005, each year being subsequently cooler than the previous and now on the edge of the 95% confidence intervals (2*SD of residuals 1975-2007). If this continues in 2009 it will be unarguable that the GCMs are missing something. Anyone pointing to a linear regression of the data, or failing to account for the high correlation between adjacent years in GMST, is either unaware of the subtleties or is willfully misrepresenting.
It will be interesting to see what the final HADCRUT3 figure is for the year but it won't significantly change from what it is currently, both RSS and UAH anomalies are in and are down on November and demonstrate that December was not warm in comparison to recent trends.
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There are methods to mathematically determine correlation, so what people perceive it to be is really irrelevant from a scientific standpoint.
looks like a slight warming
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You posted a logical trap: "only some kind of denialist...", So, not only an the impression planted, if I defend the HS I'm a denialist and the impression of said is reinforced - nothing to do with the right or wrong of the matter...
Well it's a play on words, as AGW advocates often label opponents as denialists. And the hockey stick produced in MBH98 is beyond being defended, Mann's statistical methodology was proven to be wrong, and it was only Mann's reconstruction that I was criticizing.
Well, anyway, no, we don't know what the pre instrument temperature past was like. We have a fair idea and the HS is in line with other reconstructions.Mann's reconstruction was discredited. Before then the accepted data did not show that trend. Some Reconstructions post Mann have HS attributes, those based on bore holes (regarded by some as being a better source of data) don't. The evidence for past climate variability is good, and furthermore is what would be expected.
Then you go on to say that you "don't like seeing the last 1000 years revised for idealogical purposes." which is in fact a serious allegation directed at certain scientists (as if certain scientists don't get enough flak - hey throw enough and clearly some will stick I guess ...)Fair cop
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You posted a logical trap: "only some kind of denialist...", So, not only an the impression planted, if I defend the HS I'm a denialist and the impression of said is reinforced - nothing to do with the right or wrong of the matter...
Well, anyway, no, we don't know what the pre instrument temperature past was like. We have a fair idea and the HS is in line with other reconstructions.
Then you go on to say that you "don't like seeing the last 1000 years revised for idealogical purposes." which is in fact a serious allegation directed at certain scientists (as if certain scientists don't get enough flak - hey throw enough and clearly some will stick I guess ...) , or rather said as if that too is proven! It is not - it's your perception, indeed, to adopt your debating tactics, only someone with a deeply held irrational prejudice towards sound science would say what you did - see what I mean?
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Nice example of poisoning the well that!
Not at all; there is a warming at the end of the 20th/beginning of the 21st that is distinct in the last millennium. But I don't like seeing the last 1000 years revised for idealogical purposes. AGW? evidence looks reasonable. Alarmist AG and I'd have to say I'm naturally skeptical of such an anthropocentric and catastrophic perspective, especially given the number of elephants standing in the room.
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This is a graphic (from this report) showing the changes between the old and new global temperature data sets. There is a difference, but you need good eyes a magnifying glass to see it. Whether it can be described as a 'scalp' is somewhat debatable......
It isn't the global temps that is important in this regard. It's that there was concern about datasets and methodologies, access to which were requested and denied, and it was then found that there was a significant error. Does the error show AGW isn't happening? no; does it show US temps aren't showing a warming trend since the 90's? no; but the change is still interesting and significant.
Oh, and the 'hockey stick' still stands - but it's probably best not to start that debate againThe "blade" still "stands", the flattening of the stick does not; and only some sort of denialist would claim that MBh98's statistical methods, use of bristle-cone data and HS graphic are anything other than dis-credited. Storch web site
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CA's track record is that it seeks actively for numerical or statistical imperfections in a small number of datasets or analyses which support the conclusion og AGW, then seek to undermine the conclusions by attempting to demonstrate that this invalidates the work. The purpose of this is to discredit AGW science and provide people with a reason to believe that somehow the whole global warming thing is a fake problem and will all go away.
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CA's work, when it is worthwhile, which is only occasionally, has not, in spite of much effort, actually resulted in any findings which substantively change the scientific picture of what is going on, or what is likely to happen.
CA's work now has two significant scalps: Mann's hockey stick; GISS's Temperature record. Both are important, more for demonstrating that some of the perceived flaws in the alarmist AGW view really might be worth pursuing.
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There are two possible responses to why scientists might be reluctant to share data: firstly, because they spent a long time getting it and want to keep hold of it so they can do more work, and secondly, because the institutions they work for often 'own' the copyright to the data anyway, and won't sanction its release.
But TBH, I think this is a misrepresentation. In almost all the papers I read, methodology is set out very precisely; the papers wouldn't be accepted by a journal if it wasn't, therefore, this is readily available to anyone who studies the papers. Secondly, as far as I can tell, most of the key data used in climate modelling or measurement is publically available; you can download much of it yourself from the NASA or NOAA-affiliated organisation websites. Sometimes, the LBL codes or programming protocols are kept under wraps, but this is no more than any programmer does. The claim that material is being 'kept secret' is seen as significant only if you believe in the first place that some kind of fraud or conspiracy is taking place to deceive us; otherwise, it is of no significance anyway.
Have you actually read the technical pages supporting the WG1 SPM? The content is filled with detail. There is no evidence of anything being 'kept back'. And this is the simple version; on the PCMDI site there are links to 600+ papers, all filled with details, which were used in the collation of the latest summaries. Where's the secrecy?
Respectfully,
:)P
The whole point of climateaudit is that climate scientists are not sharing datasets and methodologies.
The whole point about the GISS revisions is that CA asked for the data and were told no, they asked for the methodology for adjusting for weather stations to account for urbanisation effects and were toild no. So CA did their own digging and found the discrepencies that have now caused the GISS record to be changed.
This quote from Judith Curry at real climate highlights the issue:
Last week, Bush signed a bill on “America COMPETES”. There is a relevant part on the open exchange of data and metadata:“SEC. 1009. RELEASE OF SCIENTIFIC RESEARCH RESULTS.
(a) Principles- Not later than 90 days after the date of the enactment of this Act, the Director of the Office of Science and Technology Policy, in consultation with the Director of the Office of Management and Budget and the heads of all Federal civilian agencies that conduct scientific research, shall develop and issue an overarching set of principles to ensure the communication and open exchange of data and results to other agencies, policymakers, and the public of research conducted by a scientist employed by a Federal civilian agency and to prevent the intentional or unintentional suppression or distortion of such research findings. The principles shall encourage the open exchange of data and results of research undertaken by a scientist employed by such an agency and shall be consistent with existing Federal laws, including chapter 18 of title 35, United States Code (commonly known as the `Bayh-Dole Act’). The principles shall also take into consideration the policies of peer-reviewed scientific journals in which Federal scientists may currently publish results.”
As a climate researcher, I wholeheartedly support the above principles. In my opinion research scientists (and particularly government research scientists) should not be given any “choice” in this matter if they wish to receive government research funding, publish their research in the peer reviewed journals of the major professional societies, and have their data used in assessment reports.
Yes all this adds to the cost of doing research, and even the COMPETE bill is apparently an unfunded mandate. But it’s a cost we need to accommodate in some way. I have seen too many examples in the climate field where scientists do not want to make their data and metadata available to skeptics such as Steve McIntyre since they don’t want to see their research attacked (and this has even been condoned by a funding agency). Well, in the world of science, if you want your hypotheses and theories to be accepted, they must be able to survive attacks by skeptics. Because of its policy importance, climate research at times seems like “blood sport.” But in the long run, the credibility of climate research will suffer if climate researchers don’t “take the high ground” in engaging skeptics.
With regards to Steve McIntyre and climateaudit. In the early days of McIntyre’s attacks on the “hockey stick”, it was relatively easy to dismiss him as an industry “stooge.” Well, given his lengthy track record in actually doing work to audit climate data, it is absolutely inappropriate in my opinion to dismiss him. Climateaudit has attracted a dedicated community of climateauditors, a few of whom are knowledgeable about statistics and are interesting thinkers (the site also attracts “denialists”). For all the auditing activity at climateaudit, they have found relatively little in the way of bonafide issues that actually change something, but this is not to say that they have found nothing. So taking the high ground, lets thank Steve and climateauditors if they actually find something useful, assess it and assimilate it, and move on. Such actions by climate researchers would provide less fodder for the denialists, in my opinion.
Comment by Judith Curry — 11 August 2007 @ 8:44 AM
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The data is about as good as they can get it. Doesn't mean there aren't sometimes problems. Rarely are these significant. This adjustment makes very little - sorry - no difference to the climate trends of the past hundred years.
:)P
Parmiendes
while AF is over egging the significance, I think you and Stratos are missing some context here when you reply to him. ClimateAudit were going after the GISS stats because there were concerns about weather stations and adjustment methodologies. There was the predictable response of not sharing methodologies. CA carried on analysing regardless and discovered the error. There are quite a few conclusions that can be drawn from this, and none of them are particularly good for AGW activists ( and I don't mean AGW isn't real).
AGW science is driving policy decisions. The fact that climate scientists are frequently secretive with their data sets and methodologies is a scandal. The issues are too important.
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The denialists will pick on anything to denounce climate change.
By using the term denialist, you are using an emotive term which will of course cloud the issue, but you are also setting up a very unscientific premise: which is that the truth and significance of AGW is beyond question.
GW is an observed phenomena. AGW is a proposed factor in that phenomena which has substantive scientific evidence. There is of course an argument around how significant AGW is, with an extreme view being that it isn't significant. This variation is healthy as long as it is not un-reasoned. As an example, there is a renewed interest in indirect effects of the sun as a climate forcing agent; while these do not yet seriously challenge the accepted CO2 consensus (and probably never will) it doesn't mean they are not useful and legitimate areas of scientific interest. AGW should not be used as a witch hunt. There are some very respected scientists who have raised legitimate concerns about some claims for AGW e.g. Chris Landsea resigning from the IPCC panel and then being labeled a denialist.
Bottom line, I don't like the term denialist; it's a "you are either with us or against us" POV, that will probably end up being counter productive.
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IF this carries on for another 3-6 months, you might want to go look at the plots of CET (I may refresh my own this evening): believe me, there is absolutely NO such dramatic warming ANYWHERE in the record. As I posted earlier in the thread, at this stage this year we are something like 1.5C above where we were last year (and that off an already historically high level) on a 12 month rolling basis. It's one thing to rebound upwards from a cold start, but to explode upwards from the ceiling is quite another altogether.
Let's be clear, it cannot be sustained for much longer, but in saying that what if it is...I wonder what "common sense" will say then?
Yes, I looked up the CET graphs just after posting this, and it is unprecedented. Of course the CET starts past the height of the LIA, and it would have been most useful if we had detailed measurements extending back to the start of the MWP. Regardless, we have AGW on top of normal climate variability; I don't think it's a question of if, but how much; but we do also have to remember that natural variability is in there as well; and I think sometimes in the push to persuade about the realities of AGW some areas of the scientific community put that to one side.
Thank you for your eloquent and thoughtful response.
along with an entertaining hurricane season in gulf, ending with a nice hybrid storm (or two) hitting Europe.My understanding is that the Atlantic hurricane patterns are not significantly affected by AGW, despite shameless IPCC publicity after Katrina. Not using this to diminish arguments for AGW, but sometimes AGW proponents over-egg in order to persuade and I understand that is the case in this regard.
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No, there has never been a flat climate, but variation tends to be within given limits. In the same way that human beings (it varies though by ethnicity) grow to different heights, but the very vast majority of the population grows to between about 4'10" and 6'4". The population as a whole, however, is slowly growing taller and taller: this latter is evolution, the former is variation about the dynamic mean. That is perfectly natural behaviour. It becomes interesting when the rate of change in the dynamic mean suddenly lurches. Precisely where, very measurably, we are right now.
SF
What I don't understand is how this squares against what is the established view of the last thousand years, that does include the Medieval Warming Period and the Little Ice-Age. What we currently see in the UK is a dramatic change in the norm compared to our detailed record; probably because our basic synoptics have changed due to GW. But this doesn't look unprecedented in written history, in fact there is a pattern of warming and cooling. What makes this current pattern unprecedented?
I don't think your analogy with human height holds water at all. There is a viewpoint on NW, that the shift in UK climate is due to a shift in the position of the PJS, which in turn is a result of GW, effectively causing our climate to be far more continental in flavour. If this is the case, or some similar factor, it allows normal climatic variablity to have some very dramatic effects on regional climates.
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We have no evidence that it is not unprecedented. After all, our records only go so far back.
As far as detailed weather observations go, records for the last 2 decades look unprecedented in terms of warmth. It seems to me there is good evidence for a change in the UK's climate; i.e. this isn't normal variability. However this change may not be unprecedented in terms of all climate types, as the little ice age sounds just as dramatic with the Thames regularly freezing over and sea ice off the coast, and I would have thought that would have shown up in the CET record? And certainly the UK and the world climate has a great deal of variability, in the last 1000 years we have had the little ice age and the medieval warming period (comparable to our own present warming and possibly higher). It seems likely that the world was entering a warmer phase after the little ice age, and that AGW is acting on top of that. The interesting thing will be when the natural warming cycle ends, will climate continue to warm but more slowly; stabilise; or cool. The UK may be on a battle front, so Winters like we used to know them could return in future decades.
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From witnessing the selfish, self centred outpourings on this board, across these topics I can see why 'taxation' is favoured to volentary contributions. Maggies children have grown into the I,me, mine society and any moves that erode their spending/debt repayment powers seem to be met with stark opposition (probably 'cause in the past mum and dad paid for it all!).
Regardless of the level of uncertainty in climate change science; something green advocates seem to forget is that in a liberal society you can't tax without widespread acceptance of the justice of the taxation. How often do we see some Greenpeace spokesman on TV berating the governments lack of spine for not heavily taxing motorists for example - I mean where on earth is the reality check there? Tax motorists too much and you will get widespread resistance, and if not reversed they will be kicked out at the next election. And furthermore this is right, and it isn't selfish it is common sense. If you are going to take my money then you must prove it is in the interest of me and mine.
Climate scence can prove AGW, but can't prove that it is sufficiently serious to warrant taxing us all out of prosperity.
And if Bush's hideous government have played hard and fast with the information they pass onto the public (which they have, and indefensibly so); the same is true of the IPCC as well.
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Presuming that you are well-versed in what the prognosis of the models is, I was surprised to see you refer to 'catastrophic' scenarios; I am not sure which parts of the output this is referring to, unless it is to the larger-scale warnings of likely drought, Arctic sea ice loss, and slightly increased probability of extreme weather events. Perhaps you can clarify this.
Falling into my own trap there. In the media changes are nearly always depicted as catastrophic, with maps of the UK with large portions of the land missing due to sea rises. I'd tend to view projections of a 6'C temp increase with sea level rises of 4m by 2100 as being extreme; and would think 1'C and 1m would be more accurate.
There's a paradox here that getting people to take notice so that CO2 can be stabilized is difficult if there isn't a big enough perceived threat, but overplaying the threat just makes people cynical about AGW.
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Thanks for this. It does, however, beg the question of what it is you are sceptical about, if you think of yourself as an 'AGW accepting sceptic'. Does this mean you accept that we are warming the climate but do not accept that the consequences of this are clear, or that the consequences are not as extreme as we are often led to believe?
I believe human activity is warming the planet, the science of how CO2 does this is well understood (although I believe actual numbers in the real world are somewhat fuzzier). AGW is "proven" because it is the only credible factor that can account for current raised temperature. I do not believe the prognosis of the models, and therefore I'm sceptical of the "catastrophic" scenarios, but not dismissive. I mean it is self evident that computer models where even the raw figures for CO2 forcing are unknown, let alone the complexities of cloud formation or the cooling effect of aerosols , are pretty well worthless from a prediction POV. Climate models are undoubtedly useful for trying to understand climate, but shouldn't be the basis for policy decisions.
There seems to be a strong innate desire in people to control the activity of their fellows for moral reasons. Climate change follows that quite closely: modern man is bad, destroying the planet, islands in the Indian Ocean are being submerged because of the selfishness of the industrial nations, we need to be punished, raise taxes, limit personal transportation, no foreign holidays, etc.. And yet this is all in the present context of a raise in temperature of .6 'C, well within the range of normal variability. So the reaction we have in the media isn't measured, it's cataclysmic and its moralistic, yet what is actually happening on the ground doesn't justify this, it is not a measured or reasoned response. Industrialization and liberal democracy between them have raised the common lot of a large proportion of the planets population by an unbelievable degree, and those benefits still have to be realized for a majority. The benefits of increased undustrialisation need to be compared to the economic costs of global warming. At the moment the known costs of AGW look small, it's only when you include the amplifications of the models that the costs become more serious. This is not to say increased CO2 is OK, I think we should look at stabilizing and if possible reducing emission levels, as some sort of insurance policy. But that it should be an economic decision not a moral one. A pound spent on mitigating AGW needs to be justified on the basis of what will be achieved, and it should be considered as to where else it should be spent. Would 1 billion pounds spent on climate change have as big a humanitarian impact for instance as the same money spent on cheap drugs for Aids? The current governments aim of a 60% reduction by 2050 looks utterly unachievable unless we obtain the science of Star Trek, and yet would have no impact on global temperatures whatsoever, I mean what is that all about?
The bottom line: the current "atmosphere" of AGW isn't scientific, it is hysterical and looks like a few wanting to control the many for "moral" reasons. If you want to take my money (the basis of all AGW politics), it has to be on the basis of the hardest of facts and AGW doesn't come any where close yet.
December CET
in Spring Weather Discussion
Posted
When talking about AGW, there are two components: the greenhouse effect (GHE), the effect of infra-red active gases on atmospheric radiative transfer, and; climate sensitivity, the feedbacks that amplify and dampen climate forcings, which are believed to be high (2.5'C or greater for a doubling of CO2).
The GHE is uncontroversial and well understood, as such it is climate sensitivity that lies at the core of disagreements around global warming. The majority (if not all) of the evidence that support high climate sensitivity are based on the inability of climate models to project the 20th century climate without high sensitivity - however there is also an assumption of low internal variability, as such the argument is somewhat "boot-strapped". In this viewpoint the cooling in the 50's, 60's and 70's is due to aerosols and the high rate of warming in the 80's and 90's is almost all due to anthropogenic forcing - leaving little room for other explanations for the pattern of warming in the 20th century (e.g. a long term warming trend plus high internal variability. Such arguments are termed detection and attribution.
The modern British climate of BBQ summers and mild winters was also presented as evidence supporting the detection and attribution arguments of AGW.
It is therefore plainly problematic to the AGW hypothesis of high climate sensitivity if we are entering a post modern climate of severe winters and late summer monsoons; particularly if there are wider synoptic changes that are consistent with high internal variability (e.g. the southward migration of the jet stream).
SF's posts assumed that the modern British climate would make severe winter weather events a rarity and less extreme. The progressing pattern of the last three years therefore must have come as an unpleasant surprise. The MetO must find themselves in a similar predicament, as in the summer in their contribution to the transport winter resilience report they stated that they did not believe the previous two summers indicated a trend, and that the chances of another severe winter would still only be 5% (once every twenty years ). I find the Potsdam institute paper that TWS mentioned unconvincing as it is plainly revisionist in nature - preferring the climate regime shift work of Swanson and Tsonis as some sort of explanation of current patterns.