Hot and cold

[Vegas]

“Geologists Think the World May be Frozen Up Again.” New York Times, February 24, 1895

“Ice Age Coming Here.” Washington Post, 1923

“America in Longest Warm Spell Since 1776; Temperature Line Records a 25-year Rise” New York Times, March 27, 1933

“Scientist Says Arctic Ice Will Wipe Out Canada.” The article quoted a Yale University professor who predicted that large parts of Europe and Asia would be “wiped out” and Switzerland would be “entirely obliterated.” Chicago Tribune, August 9, 1923

“the facts of the present climate change are such that the most optimistic experts would assign near certainty to major crop failure in a decade.” New York Times, December 29, 1974

[JCD]

First we had Professor (Chicken) Little

Now we have Professor Gore

[LSU]

“Geologists Think the World May be Frozen Up Again.” New York Times, February 24, 1895

“Ice Age Coming Here.” Washington Post, 1923

“America in Longest Warm Spell Since 1776; Temperature Line Records a 25-year Rise” New York Times, March 27, 1933

“Scientist Says Arctic Ice Will Wipe Out Canada.” The article quoted a Yale University professor who predicted that large parts of Europe and Asia would be “wiped out” and Switzerland would be “entirely obliterated.” Chicago Tribune, August 9, 1923

“the facts of the present climate change are such that the most optimistic experts would assign near certainty to major crop failure in a decade.” New York Times, December 29, 1974


It's too bad we don't have more sophisticated technology and equipment than they had in 1895, 1923, 1933, and hell, even 1974.

Think if we had satellites and computers and stuff. Maybe there would've been a more accurate picture.


Probably not.

[IBC]

It's too bad we don't have more sophisticated technology and equipment than they had in 1895, 1923, 1933, and hell, even 1974.

Think if we had satellites and computers and stuff. Maybe there would've been a more accurate picture.


Probably not.
I think you could get quotes to say just about anything. Remember when the world just wasn't warming?

[Vegas]

It's too bad we don't have more sophisticated technology and equipment than they had in 1895, 1923, 1933, and hell, even 1974.

Think if we had satellites and computers and stuff. Maybe there would've been a more accurate picture.


Probably not.

Oh, so you're saying the warming is caused by more sophisticated instrumentation?

[IBC]

http://www.adventureecology.com/mission1/images/greenhouse_effect-white.gif

[IBC]

http://edmall.gsfc.nasa.gov/inv99Project.Site/Pages/trl/4-2Mean.gif

[LSU]

Oh, so you're saying the warming is caused by more sophisticated instrumentation?



No, not quite. The ability to more accurately record and analyze data has led to the current thought. Or, more accurately the back and forthness of past "conclusions" is lessened by better equipment/technology.

Would you not agree that measuring tools are more advanced than they were 80 years ago? Or even 20 years ago?

[LSU]

http://www.adventureecology.com/mission1/images/greenhouse_effect-white.gif


I don't get these maps. I mean, I understand they're looking at the relationship to the zero line, i.e., no change, but what is zero? I mean, how is that calculated?

[IBC]

I don't get these maps. I mean, I understand they're looking at the relationship to the zero line, i.e., no change, but what is zero? I mean, how is that calculated?
It is usually the deviation from current time (ie 1960 to present).

[Vegas]

No, not quite. The ability to more accurately record and analyze data has led to the current thought. Or, more accurately the back and forthness of past "conclusions" is lessened by better equipment/technology.

Would you not agree that measuring tools are more advanced than they were 80 years ago? Or even 20 years ago?

Of course tools have become better. But we can't go backwards in time and measure temperatures in the past. We have to rely on the data available. But to say that today's readings are accurate and the older data is not makes a comparison completely meaningless.

[JCD]

Strange thing about Ice Ages.

Temps tend to get warmer following them.

[LSU]

Of course tools have become better. But we can't go backwards in time and measure temperatures in the past. We have to rely on the data available. But to say that today's readings are accurate and the older data is not makes a comparison completely meaningless.


That's also not what I'm saying.

The tools, methods, knowledge of the past are not as advanced as they are now. I'm not saying the temperatures recorded are wrong. Mercury expands now just as it did back then with temperature.


The science is more advanced (better knowledge now than then) than the past.

[IBC]

http://en.wikipedia.org/wiki/Image:2000_Year_Temperature_Comparison.png

[Vegas]

As I mentioned earlier, the "hockey stick" chart that people keep using has been thoroughly debunked. Here's a fine article:

A prime piece of evidence linking human activity to climate change turns out to be an artifact of poor mathematics.

http://www.technologyreview.com/Energy/13830/

Progress in science is sometimes made by great discoveries. But science also advances when we learn that something we believed to be true isnt. When solving a jigsaw puzzle, the solution can sometimes be stymied by the fact that a wrong piece has been wedged in a key place.

In the scientific and political debate over global warming, the latest wrong piece may be the hockey stick, the famous plot (shown below), published by University of Massachusetts geoscientist Michael Mann and colleagues. This plot purports to show that we are now experiencing the warmest climate in a millennium, and that the earth, after remaining cool for centuries during the medieval era, suddenly began to heat up about 100 years ago--just at the time that the burning of coal and oil led to an increase in atmospheric levels of carbon dioxide.

I talked about this at length in my December 2003 column. Unfortunately, discussion of this plot has been so polluted by political and activist frenzy that it is hard to dig into it to reach the science. My earlier column was largely a plea to let science proceed unmolested. Unfortunately, the very importance of the issue has made careful science difficult to pursue.

But now a shock: Canadian scientists Stephen McIntyre and Ross McKitrick have uncovered a fundamental mathematical flaw in the computer program that was used to produce the hockey stick. In his original publications of the stick, Mann purported to use a standard method known as principal component analysis, or PCA, to find the dominant features in a set of more than 70 different climate records.

But it wasnt so. McIntyre and McKitrick obtained part of the program that Mann used, and they found serious problems. Not only does the program not do conventional PCA, but it handles data normalization in a way that can only be described as mistaken.

Now comes the real shocker. This improper normalization procedure tends to emphasize any data that do have the hockey stick shape, and to suppress all data that do not. To demonstrate this effect, McIntyre and McKitrick created some meaningless test data that had, on average, no trends. This method of generating random data is called Monte Carlo analysis, after the famous casino, and it is widely used in statistical analysis to test procedures. When McIntyre and McKitrick fed these random data into the Mann procedure, out popped a hockey stick shape!

That discovery hit me like a bombshell, and I suspect it is having the same effect on many others. Suddenly the hockey stick, the poster-child of the global warming community, turns out to be an artifact of poor mathematics. How could it happen? What is going on? Let me digress into a short technical discussion of how this incredible error took place.

In PCA and similar techniques, each of the (in this case, typically 70) different data sets have their averages subtracted (so they have a mean of zero), and then are multiplied by a number to make their average variation around that mean to be equal to one; in technical jargon, we say that each data set is normalized to zero mean and unit variance. In standard PCA, each data set is normalized over its complete data period; for key climate data sets that Mann used to create his hockey stick graph, this was the interval 1400-1980. But the computer program Mann used did not do that. Instead, it forced each data set to have zero mean for the time period 1902-1980, and to match the historical records for this interval. This is the time when the historical temperature is well known, so this procedure does guarantee the most accurate temperature scale. But it completely screws up PCA. PCA is mostly concerned with the data sets that have high variance, and the Mann normalization procedure tends to give very high variance to any data set with a hockey stick shape. (Such data sets have zero mean only over the 1902-1980 period, not over the longer 1400-1980 period.)

The net result: the principal component will have a hockey stick shape even if most of the data do not.


McIntyre and McKitrick sent their detailed analysis to Nature magazine for publication, and it was extensively refereed. But their paper was finally rejected. In frustration, McIntyre and McKitrick put the entire record of their submission and the referee reports on a Web page for all to see. If you look, youll see that McIntyre and McKitrick have found numerous other problems with the Mann analysis. I emphasize the bug in their PCA program simply because it is so blatant and so easy to understand. Apparently, Mann and his colleagues never tested their program with the standard Monte Carlo approach, or they would have discovered the error themselves. Other and different criticisms of the hockey stick are emerging (see, for example, the paper by Hans von Storch and colleagues in the September 30 issue of Science).

Some people may complain that McIntyre and McKitrick did not publish their results in a refereed journal. That is true--but not for lack of trying. Moreover, the paper was refereed--and even better, the referee reports are there for us to read. McIntyre and McKitricks only failure was in not convincing Nature that the paper was important enough to publish.

How does this bombshell affect what we think about global warming?

It certainly does not negate the threat of a long-term global temperature increase. In fact, McIntyre and McKitrick are careful to point out that it is hard to draw conclusions from these data, even with their corrections. Did medieval global warming take place? Last month the consensus was that it did not; now the correct answer is that nobody really knows. Uncovering errors in the Mann analysis doesnt settle the debate; it just reopens it. We now know less about the history of climate, and its natural fluctuations over century-scale time frames, than we thought we knew.

If you are concerned about global warming (as I am) and think that human-created carbon dioxide may contribute (as I do), then you still should agree that we are much better off having broken the hockey stick. Misinformation can do real harm, because it distorts predictions. Suppose, for example, that future measurements in the years 2005-2015 show a clear and distinct global cooling trend. (It could happen.) If we mistakenly took the hockey stick seriously--that is, if we believed that natural fluctuations in climate are small--then we might conclude (mistakenly) that the cooling could not be just a random fluctuation on top of a long-term warming trend, since according to the hockey stick, such fluctuations are negligible. And that might lead in turn to the mistaken conclusion that global warming predictions are a lot of hooey. If, on the other hand, we reject the hockey stick, and recognize that natural fluctuations can be large, then we will not be misled by a few years of random cooling.

A phony hockey stick is more dangerous than a broken one--if we know it is broken. It is our responsibility as scientists to look at the data in an unbiased way, and draw whatever conclusions follow. When we discover a mistake, we admit it, learn from it, and perhaps discover once again the value of caution.

[LSU]

As I mentioned earlier, the "hockey stick" chart that people keep using has been thoroughly debunked. Here's a fine article:

A prime piece of evidence linking human activity to climate change turns out to be an artifact of poor mathematics.




I read this somewhere. He sounds like a smart fellow.

As far as the laws of mathematics refer to reality, they are not certain, and as far as they are certain, they do not refer to reality. -Albert Einstein

[IBC]

National Research Council Report

At the request of the U.S. Congress, a special "Committee on Surface Temperature Reconstructions for the Past 2,000 Years" was assembled by the National Research Council's Board on Atmospheric Sciences and Climate. The Committee, consisting of 12 scientists from different disciplines, published its report in 2006.[18] The report agreed that there were statistical shortcomings in the MBH analysis, but concluded that they were small in effect. The report summarizes its main findings as follows:[19]

* The instrumentally measured warming of about 0.6 °C (1.1 °F) during the 20th century is also reflected in borehole temperature measurements, the retreat of glaciers, and other observational evidence, and can be simulated with climate models.
* Large-scale surface temperature reconstructions yield a generally consistent picture of temperature trends during the preceding millennium, including relatively warm conditions centered around A.D. 1000 (identified by some as the “Medieval Warm Period”) and a relatively cold period (or “Little Ice Age”) centered around 1700. The existence and extent of a Little Ice Age from roughly 1500 to 1850 is supported by a wide variety of evidence including ice cores, tree rings, borehole temperatures, glacier length records, and historical documents. Evidence for regional warmth during medieval times can be found in a diverse but more limited set of records including ice cores, tree rings, marine sediments, and historical sources from Europe and Asia, but the exact timing and duration of warm periods may have varied from region to region, and the magnitude and geographic extent of the warmth are uncertain.
* It can be said with a high level of confidence that global mean surface temperature was higher during the last few decades of the 20th century than during any comparable period during the preceding four centuries. This statement is justified by the consistency of the evidence from a wide variety of geographically diverse proxies.
* Less confidence can be placed in large-scale surface temperature reconstructions for the period from A.D. 900 to 1600. Presently available proxy evidence indicates that temperatures at many, but not all, individual locations were higher during the past 25 years than during any period of comparable length since A.D. 900. The uncertainties associated with reconstructing hemispheric mean or global mean temperatures from these data increase substantially backward in time through this period and are not yet fully quantified.
* Very little confidence can be assigned to statements concerning the hemispheric mean or global mean surface temperature prior to about A.D. 900 because of sparse data coverage and because the uncertainties associated with proxy data and the methods used to analyze and combine them are larger than during more recent time periods.

[IBC]

http://www.realclimate.org/index.php?p=8

[Vegas]

http://www.realclimate.org/index.php?p=8

We can go back and forth with references about the data, but that still doesn't change the fundamental issue that climate change is normal and has happened throughout history. And it has happened far enough back in history to seriously question whether it's man made.

[Roy Munson]

We were just put here to hold off the next Ice age...

[LSU]

We can go back and forth with references about the data, but that still doesn't change the fundamental issue that climate change is normal and has happened throughout history. And it has happened far enough back in history to seriously question whether it's man made.




But that fundamental issue doesn't preclude man from possibly having an effect. Especially if the trend is already a warming period, i.e., we're in a warming period that coincides with potential manmade effects, thus increasing the warming.

Perhaps if we were in a natural "cooling" period, the excess greenhouse gases would balance it out.


I doubt WE will ever know. Maybe our kids.

[Roy Munson]

All I really wanna know is where to buy property so it'll be beachfront when all the ice over land melts.

[LSU]

All I really wanna know is where to buy property so it'll be beachfront when all the ice over land melts.



Baton Rouge.

[JCD]

Funniest thing about Kyoto.

If you push the great western worriers, they'll admit that the sweeping emissions controls of Kyoto MAY lower global temperatures by a statistically insignificant 0.7 degrees within a certain period of years.

Just too funny.

[Vegas]

Funniest thing about Kyoto.

If you push the great western worriers, they'll admit that the sweeping emissions controls of Kyoto MAY lower global temperatures by a statistically insignificant 0.7 degrees within a certain period of years.

Just too funny.

I'm sorry to tell you that you are mistaken. The correct number is 0.07 degrees.

[ryr8828]

Centigrade or farenheit?

[LSU]

Funniest thing about Kyoto.

If you push the great western worriers, they'll admit that the sweeping emissions controls of Kyoto MAY lower global temperatures by a statistically insignificant 0.7 degrees within a certain period of years.

Just too funny.



But, that difference is in relation to what the temperature is now. Is it significant in relation to what the temperature is predicted to be then?

[Vegas]

But, that difference is in relation to what the temperature is now. Is it significant in relation to what the temperature is predicted to be then?

It is the projected difference in what it will be then based on their models.

[LSU]

It is the projected difference in what it will be then based on their models.


My mistake.

[LSU]

It is the projected difference in what it will be then based on their models.



But, all their other models are wrong...this is the one you choose to believe?

[Vegas]

But, all their other models are wrong...this is the one you choose to believe?

Hardly. It just shows that either the model is flawed or that the solution(s) are flowed. Or both.

They are saying that man is responsible, but the best solution they have is for us (overwhelmingly in the USA) to make these drastic lifestyle changes and to cripple our industrial output when their own modeling says that we'll get a whopping difference of 0.07 degrees.