Simon,
Re the ocean temp paper.
I remain cautious about drawing conclusions from this since there are clearly issues in interpreting the data that lead to the previous correction. Without the full paper I can't be sure how these are now treated, or what are the uncertainties.
However this is surely consistent with the known fact that temp over last few years is falling - something absolutely in line with the models.
Best wishes, Tom
PS - the models do factor in changes in solar forcing now - I am not sure how accurately but doubtless this will get better in as far as we can better predict solar output changes (I am not sure how well we can do this, so this probably is more useful in hindcasting to validate models).
Global Warming Concensus Broken
Quite a number of solar scientists predicted that this cycle will be weak due to changes in solar convection (so far results bear out their predictions). They now predict the cycle following this one will be even worse. A Dalton Minimum is not out of the question. A Maunder Minimum is possible. That would mean something like 20 to 80 years of cooling. And not just the regular solar cycle (300 years peak to peak - this cycle started in 1850, do the math) of cooling. Seriously colder.
Right now there is a warm bias in the predictions. I believe that will go away in the next 2 to 5 years. It is one of the reasons I would rather not see the BFR project tied to the AGW idea. It would take a credibility hit.
Right now there is a warm bias in the predictions. I believe that will go away in the next 2 to 5 years. It is one of the reasons I would rather not see the BFR project tied to the AGW idea. It would take a credibility hit.
Engineering is the art of making what you want from what you can get at a profit.
http://www.pubmedcentral.nih.gov/articl ... id=1810336
Solar irradiance changes are being considered seriously by the models.
If they are innacurate that will correct itself.
It is also possible solar physicists making more extreme statements about likelihood of significant future cooling are indulging in wishful thnking.
The case agsinst global cooling:
http://www.realclimate.org/index.php/ar ... et-part-2/
Best wishes, Tom
Solar irradiance changes are being considered seriously by the models.
If they are innacurate that will correct itself.
It is also possible solar physicists making more extreme statements about likelihood of significant future cooling are indulging in wishful thnking.
The case agsinst global cooling:
http://www.realclimate.org/index.php/ar ... et-part-2/
Best wishes, Tom
http://wattsupwiththat.com/2008/12/14/e ... rt-issued/
Tom,
I have no problem with waiting to see what happens. As long as we don't cripple our electrical grid while we wait. The way the Brits are doing:
http://powerandcontrol.blogspot.com/200 ... power.html
If we are entering a Dalton minimum that would be bad. If it is a Maunder Minimum worse.
No provisions are being made for such an eventuality.
Tom,
I have no problem with waiting to see what happens. As long as we don't cripple our electrical grid while we wait. The way the Brits are doing:
http://powerandcontrol.blogspot.com/200 ... power.html
If we are entering a Dalton minimum that would be bad. If it is a Maunder Minimum worse.
No provisions are being made for such an eventuality.
Engineering is the art of making what you want from what you can get at a profit.
Temperature record
I still insist the biggest problem with the 'unprecedented' warming argument and defense of it is the temperature record itself. Even groups like the IPCC state that direct and indirect temperature measurements independently confirm each other in showing an unprecedented temperature spike in the last 100-150 years. That is simply false. The strongest argument brought out is tree ring data, but tree ring data does NOT show anything abnormal in the last 100 years. Just do a search on tree ring data in a scientific journal and read all the way through the report and the methods:
Looking at the last 4 centuries of Himalayan tree ring data, they note that "The warmest 30-yr mean for the 20th century was recorded during 1945–1974. However, this warming, in the context of the past four centuries is well within the range of natural variability, since warmer springs of greater magnitude occurred in the later part of the 17th century (1662–1691)."
The link to science direct is long and makes the formating here ugly. Search for the title "Tree-Ring-Based Spring Temperature Patterns over the Past Four Centuries in Western Himalaya" by Ram R. Yadav1 and Jayendra Singh and you should find it easily.
Also look at the temperature record graphs of the last 1000 years from the 2008 Gussow-Nuna Geoscience Conference. They look absolutely nothing like the radical hockey stick graph Mann et al. try to play up.
link:http://www.cspg.org/conventions/Gussow2 ... ts/015.pdf
Want something more telling? Is there something going on with the methodology or assumptions? Take a read through this.
link:http://www.cru.uea.ac.uk/projects/soap/ ... PC2003.pdf
Specifically look at the section titled "An inconsistency in the relationship between tree-ring density and temperature". It has a graph that shows just how badly tree ring data match the measured data for the last 40 years, oddly enough the 40 years most crucial to the Mann et al. recreations. More importantly than the graph though, read the explanation of what it means:
The above facts seem to support an inference that some slowly varying factor began to exert a very widespread negative influence on the trend of these MXD data from around the middle of the 20th century, with effects at higher frequency also becoming noticeable in some high-latitude regions. For the time being, we circumvent this problem by restricting the calibration of the density data to the period before 1960. This reduces the potential overlap between temperature observations and density measurements and means that less data can be reserved for independent tests of the validity of predictive equations. This situation is far from ideal, but the alternative, using data after 1960 and thus incorporating non-temperature-related bias when fitting regression equations as a function of density variability, would invariability produce earlier estimates of past temperature that, to some extent, too warm.
Read the above closely and still try to convince anyone that badly placed assumptions aren't being used to force the data to fit. It's not a conspiracy motivation, it's just a simple matter of trying to fit tree ring data to temperature as closely as possible, but the error is plainly in considering it OK to make a correction for unknown factors since 1960, when those same corrections CANNOT be known for the last 1000. It's subtle assumptions of the analysis of the data like this that taint the real picture that the raw data tells us. Namely that tree ring data appears to miss or not be as sensitive to certain temperature peaks like what we've seen in the last short while. That means you can't point to tree rings and say today's warming is unprecedented because it's never happened in tree ring data for the 1k years, as far as the tree ring data is concerned it isn't happening today either!
Looking at the last 4 centuries of Himalayan tree ring data, they note that "The warmest 30-yr mean for the 20th century was recorded during 1945–1974. However, this warming, in the context of the past four centuries is well within the range of natural variability, since warmer springs of greater magnitude occurred in the later part of the 17th century (1662–1691)."
The link to science direct is long and makes the formating here ugly. Search for the title "Tree-Ring-Based Spring Temperature Patterns over the Past Four Centuries in Western Himalaya" by Ram R. Yadav1 and Jayendra Singh and you should find it easily.
Also look at the temperature record graphs of the last 1000 years from the 2008 Gussow-Nuna Geoscience Conference. They look absolutely nothing like the radical hockey stick graph Mann et al. try to play up.
link:http://www.cspg.org/conventions/Gussow2 ... ts/015.pdf
Want something more telling? Is there something going on with the methodology or assumptions? Take a read through this.
link:http://www.cru.uea.ac.uk/projects/soap/ ... PC2003.pdf
Specifically look at the section titled "An inconsistency in the relationship between tree-ring density and temperature". It has a graph that shows just how badly tree ring data match the measured data for the last 40 years, oddly enough the 40 years most crucial to the Mann et al. recreations. More importantly than the graph though, read the explanation of what it means:
The above facts seem to support an inference that some slowly varying factor began to exert a very widespread negative influence on the trend of these MXD data from around the middle of the 20th century, with effects at higher frequency also becoming noticeable in some high-latitude regions. For the time being, we circumvent this problem by restricting the calibration of the density data to the period before 1960. This reduces the potential overlap between temperature observations and density measurements and means that less data can be reserved for independent tests of the validity of predictive equations. This situation is far from ideal, but the alternative, using data after 1960 and thus incorporating non-temperature-related bias when fitting regression equations as a function of density variability, would invariability produce earlier estimates of past temperature that, to some extent, too warm.
Read the above closely and still try to convince anyone that badly placed assumptions aren't being used to force the data to fit. It's not a conspiracy motivation, it's just a simple matter of trying to fit tree ring data to temperature as closely as possible, but the error is plainly in considering it OK to make a correction for unknown factors since 1960, when those same corrections CANNOT be known for the last 1000. It's subtle assumptions of the analysis of the data like this that taint the real picture that the raw data tells us. Namely that tree ring data appears to miss or not be as sensitive to certain temperature peaks like what we've seen in the last short while. That means you can't point to tree rings and say today's warming is unprecedented because it's never happened in tree ring data for the 1k years, as far as the tree ring data is concerned it isn't happening today either!
-
Mike Holmes
- Posts: 308
- Joined: Thu Jun 05, 2008 1:15 pm
This is why I advised ClassicPenny to change his book for kids on the subject to not make it seem like the goal of Polywell is primarily reversing AGW. Instead making the fact that it's ecologically sound just one of several "advantages of solution" bullets. Including equally energy independence, and lower cost of energy.It is one of the reasons I would rather not see the BFR project tied to the AGW idea.
Mike
Re: thx
[ url=URL ]Temperature Over time[ /url]bcglorf wrote:thanks
Without the spaces.
Engineering is the art of making what you want from what you can get at a profit.
The temperature reconstruction of the past millenium is very complex and painstaking process. I would hate to be doing it! It uses different methods (not just tree rings) and validates methods against each other. The fact that some tree ring data is anomalous in 20th century is hardly surprising - many different factors can effect growth of trees.
I find it difficult to draw any conclusions about this subject from single papers about specific temperature proxises, when the global record uses 1000s of proxies each validated and inconsistencies removed.
I draw no conclusions from small amounts of data being wrong - this always happens andthe corrections are made (see link below, look at the data ref).
I think before I could reach a sound judgement myself about how sound existing reconstructions are I would need to do a lot of research. For now I will go with the peer-reviewed consensus.
One important point that a few posters here seem to miss. Climate models are about global temperature changes. These are much less variable than local temperature changes, which can show many long-term and short-term pertutbations due to changes in weather patterns.
What you would expect really.
Now, for those that want to reach an independent conclusion, why not read the whole (including 100s of comments, both pro & anti AGW, but mainly skeptical, trying to make sense of the data) page here:
http://www.realclimate.org/index.php/ar ... tructions/
Why do I value this more than the anti-AGW sites? Because of the openness of debate in the comments, and the large numbers of references to mainstream (not just one scientist writing outside his/her field) data. It is a big effort to read through and understand these posts (I got only through the first 30, and still am not properly informed myself on this topic) but it is worth doing.
What I am trying to say is that the science here is complex (as you would expect). It is easy to simplify a single argument and make it appear that the whole is a house of cards. The realclimate main blogs are a bit too simplified for my liking themselves (counter-propaganda). But the posts after them give a lot more detail and comparing this with the anti-AGW scare stories I know which I find more authoritative. But I can't post here one paper that would convince me - to get beyond possibly misleading one-sided arguments, all to easy to find on both sides, you need to read and understand a lot of stuff.
I will try and do it properly over the next year or so! Perhaps I will end up convinced as Simon is!
Best wishes, Tom
PS - I am myself rom UK. Our power infrastructure was blighted disastrous government deregulation & privatisation with a badly thought out market pricing mechanism that gave utilities a disincentive to invest adequately in power generation and storage capacity. Near black-outs cause the spot price to jump much higher and benefit the generators - so they have no motivation to make large long-term investment in new capacity.
They were told this would happen when they privatised.
PPS - edited to remove typos, and note that I have now skimmed all these posts. Some fascinating heated exchanges with Mcintyre (Climate Audit)
#47,#97,#99-#103
You need to read all of these open exchanges to reach your own conclusion about what is going on. If you do, it becomes clear which participants are seeking for best possible scientific truth while acknowledging (in fact being interested in details of) the uncertainties..
I find it difficult to draw any conclusions about this subject from single papers about specific temperature proxises, when the global record uses 1000s of proxies each validated and inconsistencies removed.
I draw no conclusions from small amounts of data being wrong - this always happens andthe corrections are made (see link below, look at the data ref).
I think before I could reach a sound judgement myself about how sound existing reconstructions are I would need to do a lot of research. For now I will go with the peer-reviewed consensus.
One important point that a few posters here seem to miss. Climate models are about global temperature changes. These are much less variable than local temperature changes, which can show many long-term and short-term pertutbations due to changes in weather patterns.
What you would expect really.
Now, for those that want to reach an independent conclusion, why not read the whole (including 100s of comments, both pro & anti AGW, but mainly skeptical, trying to make sense of the data) page here:
http://www.realclimate.org/index.php/ar ... tructions/
Why do I value this more than the anti-AGW sites? Because of the openness of debate in the comments, and the large numbers of references to mainstream (not just one scientist writing outside his/her field) data. It is a big effort to read through and understand these posts (I got only through the first 30, and still am not properly informed myself on this topic) but it is worth doing.
What I am trying to say is that the science here is complex (as you would expect). It is easy to simplify a single argument and make it appear that the whole is a house of cards. The realclimate main blogs are a bit too simplified for my liking themselves (counter-propaganda). But the posts after them give a lot more detail and comparing this with the anti-AGW scare stories I know which I find more authoritative. But I can't post here one paper that would convince me - to get beyond possibly misleading one-sided arguments, all to easy to find on both sides, you need to read and understand a lot of stuff.
I will try and do it properly over the next year or so! Perhaps I will end up convinced as Simon is!
Best wishes, Tom
PS - I am myself rom UK. Our power infrastructure was blighted disastrous government deregulation & privatisation with a badly thought out market pricing mechanism that gave utilities a disincentive to invest adequately in power generation and storage capacity. Near black-outs cause the spot price to jump much higher and benefit the generators - so they have no motivation to make large long-term investment in new capacity.
They were told this would happen when they privatised.
PPS - edited to remove typos, and note that I have now skimmed all these posts. Some fascinating heated exchanges with Mcintyre (Climate Audit)
#47,#97,#99-#103
You need to read all of these open exchanges to reach your own conclusion about what is going on. If you do, it becomes clear which participants are seeking for best possible scientific truth while acknowledging (in fact being interested in details of) the uncertainties..
Last edited by tomclarke on Wed Dec 17, 2008 10:40 am, edited 1 time in total.
Sorry,
Oe more thing. To make my point about global vs local temps. Any one temperature proxy will be local and exhibit much greater variation, with no likelihood that last 150 years will stand out. So:
Best wishes, Tom
Oe more thing. To make my point about global vs local temps. Any one temperature proxy will be local and exhibit much greater variation, with no likelihood that last 150 years will stand out. So:
is expected - you need careful global averages to get beyond the local (weather-pattern-influenced) temperature data. And yes weather patterns can result in long-term local deviations from global mean.Looking at the last 4 centuries of Himalayan tree ring data, they note that "The warmest 30-yr mean for the 20th century was recorded during 1945–1974. However, this warming, in the context of the past four centuries is well within the range of natural variability, since warmer springs of greater magnitude occurred in the later part of the 17th century (1662–1691)."
Best wishes, Tom
Fair 'nuf. Apologies if I overreacted.tomclarke wrote:djolds1 -
I get the impression you think I am engaged on one side of this debate with a whole load of assumptions.
I was replying where I had something relevant to say. I am not ignoring anything. I don't see it as necessary (or truthful) to rebut points made when I don't know about them.
Duane
Last edited by djolds1 on Wed Dec 17, 2008 1:29 am, edited 1 time in total.
Vae Victis
Credentialization is corrosive IMO.MSimon wrote:BTW peer reviewed papers are supposed to make their data available as well as computer codes so replication and finding code errors is possible. The scientists in the pro-AGW camp are rather notorious (not all of them) for not doing this in a timely fashion as required by the peer review process. Often a Freedom of Information request is required to extract the data and codes. And the Climate Journals are notorious for not enforcing their policies re: data and codes. It makes me suspicious.
Also let me add that aerospace engineering design reviews I have participated in are much more rigorous than most of the Climate peer review I have seen.
We note the same effect in re: Polywell. Diverse minds from diverse disciplines bring more to the table and the issues get more thoroughly hashed out.
Immanuel Kant
WHAT IS ENLIGHTEMENT?
Enlightenment is man's release from his self-incurred tutelage. Tutelage is man's inability to make use of his understanding without direction from another. Self-incurred is this tutelage when its cause lies not in lack of reason but in lack of resolution and courage to use it without direction from another. Sapere aude! "Have courage to use your own reason!"- that is the motto of enlightenment.
Laziness and cowardice are the reasons why so great a portion of mankind, after nature has long since discharged them from external direction (naturaliter maiorennes), nevertheless remains under lifelong tutelage, and why it is so easy for others to set themselves up as their guardians. It is so easy not to be of age. If I have a book which understands for me, a pastor who has a conscience for me, a physician who decides my diet, and so forth, I need not trouble myself. I need not think, if I can only pay - others will easily undertake the irksome work for me.
That the step to competence is held to be very dangerous by the far greater portion of mankind (and by the entire fair sex) - quite apart from its being arduous is seen to by those guardians who have so kindly assumed superintendence over them. After the guardians have first made their domestic cattle dumb and have made sure that these placid creatures will not dare take a single step without the harness of the cart to which they are tethered, the guardians then show them the danger which threatens if they try to go alone. Actually, however, this danger is not so great, for by falling a few times they would finally learn to walk alone. But an example of this failure makes them timid and ordinarily frightens them away from all further trials.
Each and every one of us is capable of understanding all issues presented to us. It is a matter of commitment, thought, and time, not a piece of paper stamped "Doctor of..." issued by a credentializing institution.
Quite a few luminaries of early science did not possess those scraps of parchment. I do not believe science and scholarship in general has improved since we became obsessed with them.
Duane
Last edited by djolds1 on Wed Dec 17, 2008 1:29 am, edited 1 time in total.
Vae Victis
My understanding was that, at least through 2005 (by which time the science was "settled"), climate models were incapable of backcasting even for the last 100 years, never mind 100,000.tomclarke wrote:I think many people on this thread are missing the point. GC models are based on physics and tested (not fitted) over 100,000s of years of historical data.
Duane
Last edited by djolds1 on Wed Dec 17, 2008 1:28 am, edited 1 time in total.
Vae Victis