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Decoding Climate Change with Perl, gnuplot and Google Earth

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21–30 of 35 posts

Re: Decoding Climate Change with Perl, gnuplot and Google Earth

#21
I'm sorry, isn't the elephant in the room the admission that the HadCRUT data was shown to be corrupted/inaccurate?

And that a few lines of Perl automated the error checking to such an extent that the errors just popped up?

How exactly am I to have confidence in the rest of the numbers?

Re: Decoding Climate Change with Perl, gnuplot and Google Earth

#22
post #8

Earlier quoted context omitted.

> In the case that there is no man made global warming and we act, then the outcome is still good This is the kind of statement that fuels skeptics. If the cost of "we act" exceeds the benefit, it is not "good." Skeptics are suspicious that some are using global warming to advance unrelated causes which (conveniently) require the same actions; namely, higher taxes, more regulation, bigger government. They might furth…

> If the cost of "we act" exceeds the benefit, it is not "good." I think the point is that of the four possible outcomes (in order of costs: no action and no climate change, action and climate change is real, action but no climate change, climate change is real but no action), this is the second worst outcome. All other things being equal it really comes down to a risk assessment. Yes - this, the third option, would…

You would probably think life insurance wasn't such a good bet if the premiums were 90,000 per year for a 100,000 payout. It's silly to talk about whether "climate insurance" is a good bet without assigning numbers to the premium and payout.

Re: Decoding Climate Change with Perl, gnuplot and Google Earth

#23
post #18

Comparing to the average temperature between 1961 and 1990 seems spurious. If this window of time were changed you would probably get substantially different anomaly results.

Can someone run the numbers using a different time frame as the baseline? Can someone who is not an uneducated ignoramus like myself explain why it matters?

Re: Decoding Climate Change with Perl, gnuplot and Google Earth

#24
http://en.wikipedia.org/wiki/Milankovitch_cycles Global warming WILL occur, regardless of man.

The question is what is the value of the subcomponent of temperature variation caused by man. I would argue that it is nearly impossible to isolate this value. It would require models of every other natural cause of temperature variation, from the galactic position of the solar system to the water cycle, and confidence estimates of these models. Weather is a prototypically complex and chaotic system.

Rather than allocating resources based on an answer to a nearly impossible to answer question, we should tackle questions that are more solvable like "relation between cancer rates and environmental pollution" (aka things that could have the same policy effect i.e. curbing emmisions) and remember that acute, immediate events can have a far more deleterious effect on global temperature http://en.wikipedia.org/wiki/Nuclear_winter

Re: Decoding Climate Change with Perl, gnuplot and Google Earth

#25

http://en.wikipedia.org/wiki/Milankovitch_cycles Global warming WILL occur, regardless of man. The question is what is the value of the subcomponent of temperature variation caused by man. I would argue that it is nearly impossible to isolate this value. It would require models of every other natural cause of temperature variation, from the galactic position of the solar system to the water cycle, and confidence esti…

THe Milankovitch cycles don't seem very relevant here, don't they appear across hundred thousands of years (I just skimmed the Wikipedia article)? Also, if Milankovitch can predict cycles, wouldn't it contradict your assumption that we can't infer anything about climate at all?

Re: Decoding Climate Change with Perl, gnuplot and Google Earth

#26

I'm sorry, isn't the elephant in the room the admission that the HadCRUT data was shown to be corrupted/inaccurate? And that a few lines of Perl automated the error checking to such an extent that the errors just popped up? How exactly am I to have confidence in the rest of the numbers?

Have a link about the inaccuracy of HadCRUT data? Or are you referring to the small problem mentioned in the article? As it was fixable, I would assume it is not a problem anymore - it shows the scientific process worked for once.

Re: Decoding Climate Change with Perl, gnuplot and Google Earth

#27
post #26

I'm sorry, isn't the elephant in the room the admission that the HadCRUT data was shown to be corrupted/inaccurate? And that a few lines of Perl automated the error checking to such an extent that the errors just popped up? How exactly am I to have confidence in the rest of the numbers?

Have a link about the inaccuracy of HadCRUT data? Or are you referring to the small problem mentioned in the article? As it was fixable, I would assume it is not a problem anymore - it shows the scientific process worked for once.

Characterizing it as a small problem, and "fixable" seems to minimize the very obvious fact that a few lines of Perl caught problems that should have been caught well before the data was released.

Re: Decoding Climate Change with Perl, gnuplot and Google Earth

#28
post #26

Earlier quoted context omitted.

Have a link about the inaccuracy of HadCRUT data? Or are you referring to the small problem mentioned in the article? As it was fixable, I would assume it is not a problem anymore - it shows the scientific process worked for once.

Characterizing it as a small problem, and "fixable" seems to minimize the very obvious fact that a few lines of Perl caught problems that should have been caught well before the data was released.

First, it's easy to tease out a previously unseen characteristic of a data set if you tickle it in the right way.

Second, you may be underestimating the power of "a few lines of Perl." :)

Re: Decoding Climate Change with Perl, gnuplot and Google Earth

#29

http://en.wikipedia.org/wiki/Milankovitch_cycles Global warming WILL occur, regardless of man. The question is what is the value of the subcomponent of temperature variation caused by man. I would argue that it is nearly impossible to isolate this value. It would require models of every other natural cause of temperature variation, from the galactic position of the solar system to the water cycle, and confidence esti…

Superb point about resource allocation. That such an approach hasn't been taken is the root of my skepticism about the global warming apocalypse.

Re: Decoding Climate Change with Perl, gnuplot and Google Earth

#30
post #18

Comparing to the average temperature between 1961 and 1990 seems spurious. If this window of time were changed you would probably get substantially different anomaly results.

Can someone run the numbers using a different time frame as the baseline? Can someone who is not an uneducated ignoramus like myself explain why it matters?

The shape of the graph should be exactly the same only shifted up or down. That's the good news. The bad news is that this is only true for a single station. The shape of the curve for the global average could be seriously affected by the fact that hundreds of new stations were being open around the world.
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