Mail 683 Saturday, July 16, 2011
Precise temperature vs trend
Jerry,
Given that the temperature readings at many stations are noisy, can we not learn a lot using trends even with huge error bars?
Oh forgive me. I forgot my place. The 0.1 degree accuracy level is sooo important to deciding how to structure the lives of subjects in accordance to self obvious principles.
Regards, Charles Adams, Bellevue, NE
But of course we can learn from trends with large error bars. I remind you that I often point out that there were dairy farms in Greenland in Viking times, and vineyards in Vinland and also in eastern Scotland, longer growing seasons in Europe and China, in Viking times; and this argues strongly that the Earth has been warmer in historical times than it is now. We also know that in 1776 the Hudson froze hard enough to support the transport of cannon to George Washington in Haarlem Heights; there is other gross evidence that it was much colder in 1776 than it is now. We have many measures with large error bars. We have the water temperatures from the Beagle. We have ice cores and tree rings.
It is very clear that the temperature trend since 1800 has been up. We also know that CO2 levels in the atmosphere have been rising.. Those measures are precise and repeatable: 315 parts per million by volume in 1960 to not quite 390 in 2010. This is a precise and repeatable measure and the averaging models are easily understood. It shows a trend.
Back in the 19th Century Arrhenius did some back of the envelope calculations on the effects on temperature to be expected from increases in CO2 levels. He said:
On the other hand, any doubling of the percentage of carbon dioxide in the air would raise the temperature of the earth’s surface by 4°; and if the carbon dioxide were increased fourfold, the temperature would rise by 8°
At the time there was no precise way to test this hypothesis because there were not sufficient data to determine the temperature of the Earth’s surface to a degree. Note though that Arrhenius was quite aware that the Earth was warming and had been since 1800 or so.
His law was
if the quantity of carbonic acid increases in geometric progression, the augmentation of the temperature will increase nearly in arithmetic progression.
ΔF = α ln(C/C0)
Note that this predicts the heating due to CO2. It does not say there is no other source of heating. Which brings us to this question: was there a heating trend not due to Co2 released into the atmosphere as a result of human activities? Arrhenius – a Swedish Nobel laureate – was interested in the causes of Ice Ages and their interruptions. After all, his country was covered by sheets of ice in prehistoric times, and much Nordic folklore is concerned with cold and ice and the coming of Fimbulwinter. Was human activity, specifically CO2, responsible for Scandinavia emerging from the Ice, or was there some other cause? If there be a warming trend independent of man-caused CO2, then the heating caused by CO2 would be “extra”, added on to the heating of the natural trend.
And it is precisely that question that requires accuracy in data and consistency in averaging models. The trend in warming has been up: about one degree since 1880. This is generally reported in tenths of a degree, but often even in hundredths of a degree in quite scientific-sounding reports.
Then there is this sort of thing:
The official NASA temperature graphs make it appear that we are dealing with dramatic trends, but close inspection shows that most of those are actually reporting changes of a tenth of a degree per decade – one degree in a century. How much of that is man made and how much due to something else is not easily ascertained.
All these arguments depend on reliable data at great accuracy.
A great deal of the Republic’s investment capital is determined by government policies which are themselves generated from the Global Warming theories. The Global Warming policies have caused a great deal of unemployment and are responsible for much of our economic distress. How much effect the US has on actual CO2 generation is not clear: China and India are building coal fired power plants.
Low cost energy plus economic freedom is a sure fire formula for economic prosperity. The US has restricted economic freedom and raised the cost of energy as a result of climate change theories. It would seem to me important to base those policies on sound and accurate data.
We ought also to be looking at just what effect our Green policies actually have on the world: are we just getting out of the way for China and India? Would it be better to have American prosperity and fund research on technologies that can bring about climate change in directions we want?
And what direction do we want, anyway?
= =
What shall we set the Earth’s thermostat to?
I’ve enjoyed your comments on AGW, etc.
As an engineer, my questions to the "Climate Scientist" convention from Hearth and Earth would be:
1) WHAT IS THE "CORRECT" AVERAGE TEMPERATURE? Don’t we need to know this first before we can determine what deviance is detrimental?
2) Apart from the # temp samples and placement, what would an "accurate average global temperature" mean anyway? If half the planet was 150F and half was 0F would that be just the same to a "climate scientist" as the entire planet being a uniform balmy 75F?? Same average all we care about? Where is the deference to thermal differences which create weather, not to mention the uncertainty of its measurement?
3) If we have established the correct target average global temperature (of course nobody can, even if it made any sense) to set the thermostat at, then wouldn’t we have a moral obligation to construct something to connect that thermostat to? A Global HVAC system that can reign in variations *either way*, not just choke off industrial progress with carbon taxes to keep us cooler, or warmer, or whatever is the latest Marxist scam.
Or maybe our moral obligation is to meet our moral obligations by observing more and learning more and rushing to "end debate" less?
Cheers
Jeff D
We do not seem to have any agreement on where we ought to set the thermostat, nor are we working very hard on industrial or more likely biological processes for extraction of CO2 from the atmosphere. There’s a lot we should be studying; instead we rush to make policies which may not have any great effect on the world C02 levels.
Dr. Pournelle,
Just a quick note. Trying to pound it out before my netbook battery dies.
Did you see the interview of Bill Gates done by Wired Magazine? It was about energy, and I think you and Mr. gates share an attitude or two. I’m not a big Gates fan, but he seems to be making sense here. Here is the URL:
http://www.wired.com/magazine/2011/06/mf_qagates
Obesa Cantavit,
Douglas Knapp
A good interview. It is worth some close attention. In A Step Farther Out I long ago dealt with using garbage to generate industry: but note that the government mandates on biofuels have resulted in a lot of distortions, and now there is a mandate to use cellulosic ethanol when none is available. I wrote on this long ago, and things haven’t changed much. My solution to this would be prizes: if the Gates Foundation were to put up a $1 billion prize for production of industrial quantities of biodiesel fuel at economic costs – the wording of the prizew would have to be carefully done, but it’s not all that hard – then either it happens or it doesn’t. No government mandates needed, and no costs to anyone but investors until it’s achieved. For that matter, though, a $10 billion prize would get us a private base on the Moon. If I could convince Gates of anything, it would be to put up about $20 billion in Prizes in various areas of his choosing: show that prizes work.
Thanks for the reference, and I agree it’s worth your time.
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A nice, thorough history of the use of nuclear power generation in space.
http://www.cbsnews.com/stories/2011/06/30/scitech/main20075735.shtml
–Gary Pavek
I will note that after all was said and done, the number of people killed off site by the Japanese nuclear disaster following the earthquake and tsunami is lower than the number killed in mine accidents so far this year.
Nuclear power remains the “greenest” and most reliable energy source we have. It is not “safe” perhaps, but we know the limits of its effect. Chernobyl is about the worst disaster and it was pretty minimal compared to – well, to the worst scenarios of global warming, as an example. I don’t like unlimited dumping of CO2 into the atmosphere. I think there are better ways to deal with that threat than wrecking the economy.
