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  #51  
Old 12/22/2007, 09:08 PM
greenbean36191 greenbean36191 is offline
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Last week the rest of the world pushed for a treaty to cap and reduce emissions. They also booed the US for being the biggest contributor to anthropogenic warming but refusing to agree to any significant action.

Meanwhile back at home we set a goal to meet an average of 35 mpg within 12 years. Wow, how ambitious! I drive a car that exceeded those standards almost 20 years ago. It took us 8 years to get to the moon but we're setting a goal of 10 mpg better over 12 years? I'm not sure we really deserve a pat on the back for that.

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You put your faith in a UN political committee? Look how well they handle other activities. Why do you think they are right this time?
The IPCC was a committee of scientists from UN countries, not politicians. Skeptics such as Dr. Christy were also included as members of the panel to ensure both sides were represented. They were simply asked to review the pre-existing literature on the subject and put it in useful terms for policymakers. Everything they said is already represented in the scientific literature except for their recommendations of how we should deal with the problems. Can you point out something they specifically got wrong based on sound science?
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  #52  
Old 12/22/2007, 09:42 PM
Buckeye ME Buckeye ME is offline
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Meanwhile back at home we set a goal to meet an average of 35 mpg within 12 years. Wow, how ambitious! I drive a car that exceeded those standards almost 20 years ago. It took us 8 years to get to the moon but we're setting a goal of 10 mpg better over 12 years? I'm not sure we really deserve a pat on the back for that.
That's quite ignorant to say a 40% increase in gas mileage is as simple as you think it is. Sure, we could all be driving around in 4 cylinder Corollas, but that is not practical. We might as well ask everyone to ride their bike to work.

35 mpg and American's desire for powerful cars do not go hand in hand. You cannot blame politicians for that.
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  #53  
Old 12/23/2007, 08:39 AM
samtheman samtheman is offline
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If you could give me an example of anything the UN does that is done well, I could possibly believe a political body like the IPCC can make unbiased scientific recommendations.
Why the need for a consensus, if the data stands on its own?

Oh that's right, there is no data, just mathamatical models and then a little correlation analysis.

Are there any other economy wreaking decisions that we utilize unvarifiable models to guide us?

Its all voodoo.
  #54  
Old 12/23/2007, 09:04 AM
greenbean36191 greenbean36191 is offline
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Thinking like that is exactly why nothing gets done. There's nothing hard about it at all except convincing the public that it needs to be done. The technology has been around for years. Within 12 years we could do away with gas as the primary fuel source altogether if there was enough demand.

Quote:
Sure, we could all be driving around in 4 cylinder Corollas, but that is not practical. We might as well ask everyone to ride their bike to work.
Yeah, you're right. Corollas are sooo uncomfortable and extremely impractical for all that harsh driving people do. SUVs and muscle cars are definitely better suited to interstate driving and those high speed commutes to work.

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35 mpg and American's desire for powerful cars do not go hand in hand. You cannot blame politicians for that.
They don't go hand in hand if you insist on using 1970's technology like American carmakers do. Like I said my car is almost 20 years old and it makes about 75 HP/liter as compared to a 2008 mustang that makes about 50 HP/liter. I'm not blaming politicians at all. I'm blaming the automakers for sticking to the status quo and the citizens for not demanding any more from them.
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  #55  
Old 12/23/2007, 12:12 PM
Buckeye ME Buckeye ME is offline
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Automakers are selling cars the public wants. That's how capitalism works.

If there was demand for 4 million Corollas/year, we would be making that many.

I don't know how tall you are, but a Corolla does suck for me. People above 6' tall are not meant to drive those.
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  #56  
Old 12/23/2007, 12:17 PM
Buckeye ME Buckeye ME is offline
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The technology has been around for years. Within 12 years we could do away with gas as the primary fuel source altogether if there was enough demand.
And what mystical technology is this you're talking about? There is no magic propulsion system that will eliminate gas in the immediate future. You probably also believe the government is holding a patent on a 300 mpg engine so they can keep their "oil buddies" in business.
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  #57  
Old 12/23/2007, 03:47 PM
greenbean36191 greenbean36191 is offline
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I was actually talking about the technology to reach the 35 mpg mark. For the last 30 years American manufacturers have been pouring their R&D money into improving the efficiency of tired old designs without trying anything really new. There's only so much you can do to an old design to improve flow and cooling and cut weight. I agree that it would be quite a feat to improve efficiency 40% that way.

Meanwhile European and Japanese manufacturers have been working on real innovations. Japanese manufacturers have been using variable timing for about 20 years whereas American manufacturers joined the club 2 years ago. Americans are still sticking to traditional gearboxes while other countries have made major improvements in the performance of newer types of transmissions. American manufacturers were behind in the transition from coil-distributor ignitions too. Those are just a few existing technologies that improve efficiency without sacrificing power.

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Automakers are selling cars the public wants. That's how capitalism works.
Yep, and that's part of the reason American manufacturers have been suffering from poor sales lately while Japanese manufacturers like Toyota are seeing record profits and increased sales of fuel-efficient vehicles.

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And what mystical technology is this you're talking about? There is no magic propulsion system that will eliminate gas in the immediate future.
Given how little people care about gas prices or environmental impacts there isn't anything that's poised to knock off gas. That's not because alternatives like biofuel and fuel cells don't have the potential to be better or have insurmountable problems, but because there's not a terrible amount of effort being put into developing them further. Biodiesel works great, but there's no infrastructure to manufacture and distribute it. Hydrogen has the same problems, plus a few others with the production methods. The problems with both could be addressed within 12 years if there was a push to do it.

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You probably also believe the government is holding a patent on a 300 mpg engine so they can keep their "oil buddies" in business.
No.
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  #58  
Old 12/23/2007, 09:06 PM
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Just an aside, something to think of in your research.

Hydrogen is most produced from natural gas. The extraction of hydrogen pumps tons of CO2 and other green house gases into the atmosphere. While it might be an alternative for gasoline it is not a clean one.

Bio fuels are terribly inefficient. It takes a gallon of fuel to produce 1.2 gallons of bio fuel.
  #59  
Old 12/23/2007, 09:09 PM
greenbean36191 greenbean36191 is offline
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If you could give me an example of anything the UN does that is done well, I could possibly believe a political body like the IPCC can make unbiased scientific recommendations.
CITES
The Convention on Biodiversity
The Bonn Convention

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Why the need for a consensus, if the data stands on its own?
Because that's what's reflected in the scientific literature.

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Oh that's right, there is no data, just mathamatical models and then a little correlation analysis.
Actually those models are based on data. There's observational data, proxy data like sediment cores, direct measurements from some sources like trapped air in ice cores, biological data such as range shifts, and changes in the timing of seasonal events just to name the stuff I can think of off the top of my head.

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Are there any other economy wreaking decisions that we utilize unvarifiable models to guide us?
What economy wrecking decision are we talking about basing on unverifiable models? One really big one comes to mind, but it's against RC policy to talk about it.
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  #60  
Old 12/23/2007, 09:21 PM
greenbean36191 greenbean36191 is offline
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Hydrogen is most produced from natural gas. The extraction of hydrogen pumps tons of CO2 and other green house gases into the atmosphere. While it might be an alternative for gasoline it is not a clean one.

Bio fuels are terribly inefficient. It takes a gallon of fuel to produce 1.2 gallons of bio fuel.
Those are the kinds of problems with production methods I was talking about. None of them are insurmountable; the technology just isn't mature yet because there hasn't been much public will to develop it. We also have ways of producing H2 from water and electricity which can be produced from renewable sources. The trouble with that though is it's slow. Last I heard the production of biofuel was worse than 1:1. You have to keep in mind that we've put almost no effort into optimizing either process though so we shouldn't write them off. We have to judge the alternatives based on their potential, not where they're at now. Keep in mind when oil refining first started that people though gasoline had no potential and literally threw it out.
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  #61  
Old 12/24/2007, 01:50 AM
HippieSmell HippieSmell is offline
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Quote:
Originally posted by MCary
Just an aside, something to think of in your research.

Hydrogen is most produced from natural gas. The extraction of hydrogen pumps tons of CO2 and other green house gases into the atmosphere. While it might be an alternative for gasoline it is not a clean one.

Bio fuels are terribly inefficient. It takes a gallon of fuel to produce 1.2 gallons of bio fuel.
Wow, I did a double take when I saw that you posted. Where have you been?
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  #62  
Old 12/24/2007, 02:28 AM
HippieSmell HippieSmell is offline
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Quote:
Originally posted by Buckeye ME
Automakers are selling cars the public wants. That's how capitalism works.
I like capitalism because it is the best financial system to date, but unrestricted capitalism has major faults, this being an example. There is also WAYYYY too much business influence in politics to even suggest a completely free market anyway. The vast majority of people want this technology to move forward, but there is a lot of pressure to keep the status quo.
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  #63  
Old 12/24/2007, 01:49 PM
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Don't want to necessarily take this discussion another direction, but even as a capitalist pig, I am all for and will do anything I can to contribute to the development and use of alternative energy. I find it rediculous that we pay for the means of our own distruction, terroristly speaking. The sooner we no longer need the raw materials of the middle east the better.

Dafur fact. United States and its allies is reluctant to interfere in the genocide of Dafur because it doesn't want to **** off China, who gets alot of oil from Sudan. I don't care who you are, that's just not right.

And if the air gets cleaner and the reefs do better, nice side gravy.

Mike
  #64  
Old 12/24/2007, 01:51 PM
MCary MCary is offline
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I like capitalism because it is the best financial system to date, but unrestricted capitalism has major faults, this being an example. There is also WAYYYY too much business influence in politics to even suggest a completely free market anyway. The vast majority of people want this technology to move forward, but there is a lot of pressure to keep the status quo.
Amen
  #65  
Old 12/24/2007, 02:01 PM
chrissreef chrissreef is offline
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"The vast majority of people want this technology to move forward, but there is a lot of pressure to keep the status quo."

that's because the lowest bidder wins and moving forward costs $$. the US consumer and industries hold the importance of monitary cost of something very high - even above quality... the government as well (I work for a govt subcontractor and whoever bids the lowest wins 95%+ orders and it requires a TON of justification paperwork if the lowest bidder isn't used). Look at the success of walmart... do you think many of those consumers care about the environment?
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  #66  
Old 12/24/2007, 04:29 PM
hdodd hdodd is offline
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As a kinda new member of this site and a new "reefer", I found it interesting, but not surprising, that there would be a section on this "global warming" matter. I probably have more age on me than most writing here. I have no real science background, so I can't authoritatively contribute much but ask probably stupid questions. Like, how do we reach such grand conclusions about natural events on this planet when the planet is over 4 billion years old and our ability to record observations is less than 200 years? Is it not true that there is evidence to suggest the earth cycles, i.e., moves from warm to cold to warm to cold, etc.... and that this cycle has been ongoing well prior to man even finding the value of carbon? If that is the case, then how can we so dramatically reach these almost religious like conclusions about how man is responsible for what is otherwise thought by some experts to be a totally normal and natural event, i.e. warming (like where did the great lakes come from). What concerns me the most about all of this is the fact that it is now political, harshly so. A lay person like me has nothing to rely upon except screaming idiots pounding away on their positions. Being no fool, I smell a rat, I smell an agenda that is not limited to just the issue of man's contribution to "warming". I smell a political movement that is unlimited in its view of what the world should look like at all levels. Now with that, I have a fox face, it is beautiful, but I want to put more fish in the tank, a 120 gal. all paraments very good. Any ideas?????
  #67  
Old 12/24/2007, 08:23 PM
chrissreef chrissreef is offline
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hdodd - good points. I disagree but yes there are "factual" opinions on both sides of the fence (just as there are many many other things). The only thing we can do is make personal choices based on what the "screaming idiots" are saying.

Personally, I wish everyone would pile all of their garbage in their garage for a year and tell me with a straight face that we aren't impacting the world. or have an aquarium for 15yrs without doing a water change... this would easily illustrate that a balance needs to be made. Imports need an equal export... and right now it's not equal which makes me believe things (Co2) are piling up in the atmosphere (and with increasing populations it's increasing at a faster pace every year)... thus the fat person keeps getting fatter.

i take my global warming position outside of the "facts" people say about global warming since our records only go back 200 yrs and can be measured further through analysis. I believe it merely because of the import/export balance that needs to occur.
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  #68  
Old 12/24/2007, 08:36 PM
greenbean36191 greenbean36191 is offline
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Like, how do we reach such grand conclusions about natural events on this planet when the planet is over 4 billion years old and our ability to record observations is less than 200 years?
We have proxy data that overlaps with our 200 years of direct observations. Proxy data is basically an indirect measure of something else. Ice cores are one of the most publicized sources of proxy data. You can look the thickness and structure of snow layers and tell how wet, cold, or windy a year is. You can also look at the amount and composition of dust or ash in the snow and tell how dry or windy it is where the dust came from. The ice also traps microscopic bubbles of air that allow for direct measurement of ancient air. You can also look at the ratios of different oxygen isotopes and tell how much sun was hitting the upper atmosphere. You can do similar things with cores from coral reefs, ocean and lake sediments, and tree rings (from live and dead trees). The 200 years of direct observations plus occasional observations before that give us a check on the calibration of the proxies. Obviously I'm oversimplifying a lot, but Richard Alley has a great book called The Two Mile Time Machine that does a really good job of explaining how we know what we know in easy to understand terms.

Quote:
Is it not true that there is evidence to suggest the earth cycles, i.e., moves from warm to cold to warm to cold, etc.... and that this cycle has been ongoing well prior to man even finding the value of carbon?
There is no doubt. Dr. Alley's book does a great job of putting past and recent trends into perspective too.

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If that is the case, then how can we so dramatically reach these almost religious like conclusions about how man is responsible for what is otherwise thought by some experts to be a totally normal and natural event, i.e. warming (like where did the great lakes come from).
I know of no experts on the subject that believe that the current trend is a totally normal and natural event. They certainly aren't publishing anything in the scientific journals to that effect. Even John Christy has acknowledged that humans are having an impact, though he disagrees with most scientists on the extent of our impact.

I think this question is a great example of the false dichotomy that's been set up by skeptics. They would have you think that the only options are that either humans are causing the current warming (and that that's what scientists are claiming) or that it's caused by natural variations. Given that we have good records of huge changes that predate humans, the second of the two seems like the obvious choice. In reality there is also the option that the current trend is the result of natural fluctuations being amplified by the impact of humans. That's the option supported by science. There is currently no scientific debate over whether or not we're a factor. The only debate it how much.

So how do we know that we're partly to blame? We know what greenhouse gases like CO2, water, and methane do in the atmosphere. We know that we produce a lot of them- more than the planet can sink. There is no way we know of that the excess can not have an impact so the question becomes how much. To figure out that impact we have to know how much of those gases we've produced vs how much is produced naturally and how much is sunk as well as feedbacks like changes in the reflectivity of ocean water vs. ice or clouds vs. clear skies. When you combine all of that you can make a model. If you only include natural things like volcanoes, orbital changes, changes in the sun's output, etc. The model matches the real world data up until about the time of the industrial revolution, where it starts to underestimate the trend. If you add in the human impacts suddenly the model starts matching the real world data the whole way. No, it's not perfect, but the fact that we can get the model to fall that closely to what actually happened shows that we have a pretty good understanding of what caused the changes- at least well enough to predict the trends.
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  #69  
Old 12/25/2007, 12:17 AM
chrissreef chrissreef is offline
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great writeup greenbean, thanks =)
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  #70  
Old 12/25/2007, 06:03 AM
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Thanks for the book reference, will get it. The description of proxy data is very helpful. It certainly makes sense, and even I can understand this, that human presence on the planet contributes something to the environment, good or bad. Well over my head, but a possible question is so, okay, we are bad for the environment, so what? If the natural course of things is for that to be, then???????????????? In other words, we take a leap from the hard and fast "science" and move into the "whys?". That, I suppose, becomes more a philosophical discussion. On the proxy data, if I were to create a line representing the length of time the earth has been around, (or more relevant, the length of time the earth's environment is similar to today's), what percentage of that time would be covered by the proxy data? All of that time, only a fraction of that time? My point is that proxy data seems to be very important to the analysis and I sense that it is a very powerful tool used for the development of "models", then the degree of confidence in the data must be high. If my low level understanding is at all close, then is there a generally accepted level of confidence in the proxy data and how is that confidence determined? But more important, no one has answered my fish question, what next folks, what next????
  #71  
Old 12/25/2007, 09:42 AM
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There have been at least four major ice ages in the Earth's past. Outside these periods, the Earth seems to have been ice-free even in high latitudes.

The earliest hypothesized ice age, called the Huronian, was around 2.7 to 2.3 billion years ago during the early Proterozoic Eon.

The earliest well-documented ice age, and probably the most severe of the last 1 billion years, occurred from 850 to 630 million years ago (the Cryogenian period) and may have produced a Snowball Earth in which permanent ice covered the entire globe. This ended very rapidly as water vapor returned to Earth's atmosphere. It has been suggested that the end of this ice age was responsible for the subsequent Ediacaran and Cambrian Explosion, though this theory is recent and controversial.


Sediment records showing the fluctuating sequences of glacials and interglacials during the last several million years.A minor ice age, the Andean-Saharan, occurred from 460 to 430 million years ago, during the Late Ordovician and the Silurian period. There were extensive polar ice caps at intervals from 350 to 260 million years ago, during the Carboniferous and early Permian Periods, associated with the Karoo Ice Age.

The present ice age began 40 million years ago with the growth of an ice sheet in Antarctica. It intensified during the late Pliocene, around 3 million years ago, with the spread of ice sheets in the Northern Hemisphere, and has continued in the Pleistocene. Since then, the world has seen cycles of glaciation with ice sheets advancing and retreating on 40,000- and 100,000-year time scales. The most recent glacial period ended about ten thousand years ago.

Ice ages can be further divided by location and time; for example, the names Riss (180,000–130,000 years bp) and Würm (70,000–10,000 years bp) refer specifically to glaciation in the Alpine region. Note that the maximum extent of the ice is not maintained for the full interval. Unfortunately, the scouring action of each glaciation tends to remove most of the evidence of prior ice sheets almost completely, except in regions where the later sheet does not achieve full coverage. It is possible that glacial periods other than those above, especially in the Precambrian, have been overlooked because of scarcity of exposed rocks from high latitudes from older periods.
The above is from Wikepedia, and I hate being a pest about this. The book referred, and I haven't read it just yet, seems to talk about looking at 100,000 years, yet the total history of climate change is so very much longer. I know nothing about the other forms of proxy data gathering, but as a lay person, you may see my problem. Thanks for indulging.
  #72  
Old 12/25/2007, 10:00 AM
billsreef billsreef is offline
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Quote:
Originally posted by greenbean36191
Guys leave politics and the blame game out of this. I realize that it's temping, but it's not allowed on RC and there's plenty to talk about on the issue without getting into it.
Seems this needs repeating. I know it can be hard to keep the politics out of the discussion, but it needs to be done. Your free to debate, politely, the science, but the politics are a no go.
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  #73  
Old 12/26/2007, 10:41 AM
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Loehle, C. 2007. A 2000-year global temperature reconstruction based on non-treering proxies. Energy & Environment 18(7-8): 1049-1058.

Note: Data presented in Figure 1 is available in a CSV file.

Historical data provide a baseline for judging how anomalous recent temperature changes are and for assessing the degree to which organisms are likely to be adversely affected by current or future warming. Climate histories are commonly reconstructed from a variety of sources, including ice cores, tree rings, and sediment. Tree-ring data, being the most abundant for recent centuries, tend to dominate reconstructions. There are reasons to believe that tree ring data may not properly capture long-term climate changes. In this study, eighteen 2000-year-long series were obtained that were not based on tree ring data. Data in each series were smoothed with a 30-year running mean. All data were then converted to anomalies by subtracting the mean of each series from that series. The overall mean series was then computed by simple averaging. The mean time series shows quite coherent structure. The mean series shows the Medieval Warm Period (MWP) and Little Ice Age (LIA) quite clearly, with the MWP being approximately 0.3°C warmer than 20th century values at these eighteen sites.

Copyright © 2007 by Multi-Science Publishing Co. Ltd. All rights reserved. Article posted on this website with permission.
  #74  
Old 12/26/2007, 10:44 AM
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http://wattsupwiththat.wordpress.com...ature-part-34/
  #75  
Old 12/26/2007, 07:37 PM
greenbean36191 greenbean36191 is offline
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I don't have access to the Loehle paper since E&E isn't a very widely distributed "journal," but here's a fun critique of it. http://www.realclimate.org/index.php...constructions/
If the criticisms he points out are true then maybe I'm not missing out on much with E&E.

Quote:
http://wattsupwiththat.wordpress.co...rature-part-34/
That really is a bad place to take the temperature for use in trend analysis and it's true that it's not unique. However it's not a surprise to climatologists. The heat island effect is already accounted for in the analysis. There are enough land based sites that aren't suffering from the heat island effect to say that the trend really does exist and provide us with reliable data. We also have a significant amount of corroborating data taken at sea along with sea surface temperatures. That same data is also what allows us to tell that the heat island effect isn't just theoretical.

Quote:
On the proxy data, if I were to create a line representing the length of time the earth has been around, (or more relevant, the length of time the earth's environment is similar to today's), what percentage of that time would be covered by the proxy data? All of that time, only a fraction of that time?
The Earth is about 4.6 billion years old and in some sense we have proxies dating back to about 3-4 billion. As you go farther back in time though the number of proxies, the types of measurements you can get, and the resolution all decrease. For the modern era you could look at things such as direct observations, tree-rings, coral cores, sediment cores, and ice cores and the overlap and large number of data points provide a lot of clarity. If you want to look back a few thousand years though, you lose the tree rings. After about 100,000 years you start to lose the majority of the ice cores. After 800,000 years all of the ice cores end and beyond that eventually all you have is the geologic record, which doesn't provide a whole lot of precision.

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If my low level understanding is at all close, then is there a generally accepted level of confidence in the proxy data and how is that confidence determined?
Where they overlap you can compare the proxies between each other and the observational data. The amount of variation between datasets allows you to statistically determine the margin of error with a defined confidence level. 95% is pretty much the the standard confidence interval, so that there's a 95% chance that the actual value falls within the margin of error. As the variability of the data decreases or the number of data points increases the uncertainty shrinks. For the most recent data we have lots of data points, so from a statistical point of view, low uncertainty and 95% confidence. As we go farther back we still have 95% confidence but uncertainty increases if that make sense. Basically after we calibrate the data using known values it comes down to statistics to tell us what we can make of it.

Quote:
The book referred, and I haven't read it just yet, seems to talk about looking at 100,000 years, yet the total history of climate change is so very much longer. I know nothing about the other forms of proxy data gathering, but as a lay person, you may see my problem.
Alley was one of the scientists involved in drilling the Greenland ice cores, which only go back about 100,000 years, so that's what he talks about most. However other proxies including other ice cores go back much further and the book does talk a fair bit about those other data sources.

Towards the very old end of the spectrum you get more into areas where you can tell that it was hotter or warmer but you can't tell by how much. That's fairly immaterial for studying future trends though. We already have records for a long enough time period (including large changes) to verify the models.
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