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| quote: | Originally posted by Shakka
Man, we must really be doing some damage. Talk about galactic warming! Maybe we should send some saplings to Neptune on the next Voyager mission. We could send Al Gore to plant them.
http://www.worldclimatereport.com/i...8/neptune-news/ |
I got a little naturally suspicious about this paper by Hammel and Lockwood (2007) that was the main source of reference for the article you used, Shakka. Upon further examination (and some admittedly further reading from other scientists and their respective blogs, I believe my suspicions were confirmed, and it further ties my notion of parallels between creationists works and global warming skeptics. Here's why:
The source for the article was given:
Hammel, H. B., and G. W. Lockwood, (2007). Suggestive correlations between the brightness of Neptune, solar variability, and Earth’s temperature, Geophysical Research Letters, 34, L08203, doi:10.1029/2006GL028764.
And first off, NONE of the correlations cited by Hammel and Lockwood are significant, and they state as such (with a bit of disappointment on their part):
| quote: | | Although correlations between Neptune's brightness and Earth's temperature anomaly--and between Neptune and two models of solar variability--are visually compelling, at this time they are not statistically significant due to the limited degrees of freedom of the various time series. Nevertheless, the striking similarity of the temporal patterns of variation should not be ignored simply because of low formal statistical significance. |
You notice that little word "formal" in their tone? That's pretty fucking cute on their part, IMO, because they're doing their darnest to belittle that little formality of "statistical significance" in their paper. That's just in their abstract, too. In the actual paper they go further with their cuteness:
| quote: | | Low formal statistical significance does not mean the correlations we find are in fact spurious, only that we cannot demonstrate otherwise. |
Ummm, that's just patently absurd on the face of scientific scrutiny. If something is not significant, to which their findings clearly are not, then they really shouldn't bitch and moan about it. Just accept the lack of significance in their correlation and move the fuck on.
It gets better. They move their level of significance almost up to fucking 20%, and how they achieve that bewilders an amateur researcher hobbyist like myself:
| quote: | | "We assume four degrees of freedom for the decades long Neptune data set, based on the number of zero crossings in the residual plots in Figure 4." |
FOUR DEGREES OF FREEDOM?!?!?!? WHAT??!?!?!?
Furthermore, they selected a lag of 17 years between their datasets in order to get the most out of their correlations, which strangely their tests of significance don't even account for this.
Right there alone should be enough to discount the paper. Attempting to run their level of significance up to 4 degrees is beyond ridiculous and untenable. At most I've seen papers bumping up levels of significance to 10%, and those very few papers admit as much that their significance levels are so high based on initial experimental or pilot-type research (which in case you're wondering, that's 2 degrees of freedom).
So really, if we go by the known scientific axiom that "correlation does not mean causation", then what the fuck should we conclude when there's a complete LACK of causation like this?
Secondly, the correlations cited by Hammel and Lockwood are primarily sourced from Foukal (2002), A Comparison of Variable Solar Total and Ultraviolet Irradiance Outputs in the 20th Century, Geophysical Research Letters, 29, p. 2089.
This paper, which was apparently fine 5 years ago, is a bit dated in scientific terms for examining total solar irradiance (TSI). For Hammel and Lockwood to use that paper for their work which was published THIS YEAR does not make a very strong case for their argument of correlation. What is considered a more higher standard of current data before the satellite era is Lean (2000), Evolution of the Sun’s Spectral Irradiance Since the Maunder Minimum, Geophysical Research Letters, 27, p. 2425. This paper, although originally published in 2000, has actually been updated in 2004, which takes into account satellite measurements of TSI (and the recent satellite data is more closely aligned with their original calculations back in 2000 versus Foukal).
And guess what? That darn data used by Foukal just ain't supported by satellite measurements. What's clear in the current satellite measurements is there is nothing of the sort of a 2.3 W/m^2 increase in TSI from 1982 to 1990. The only significant change is the variations due to the solar cycle, with full amplitude of only 1 W/m^2, and the average value of TSI shows no real change at all.
What's even worse, the Foukal paper stops with data just a little beyond 1990, however the Lean paper moves further past 2000, with satellite data going even further. Why the fuck did Hammel and Lockwood not even consider up to date measurements?
Furthermore, the graphs cited by Hammel and Lockwood shows a variation in Neptune's brightness of 0.15 magnitudes, or a 15% difference radiation. However, if we assume such a variation is caused by the sun, then we must assume that it would have to increase its brightness by the SAME RATIO. However, upon examination of Foukal's paper, we only see a variation of 0.017%.
Strange, ain't it?
Also, Lockwood and Hammel source an eleven year cycle of solar and earth irradiance, showing a rising trend in this from 1960 and from 1980. But strangely, they do not cite the trend on Neptune in the same period. Strange that. Hammel and Lockwood cite this paper:
http://oposite.stsci.edu/pubinfo/pr/2003/17/paper.pdf
which states the following:
| quote: | | the combined disk-averaged variation from 1972 to 2002 is consistent with a simple seasonal model having a hemispheric response delay relative to solar forcing of 30 years. |
Hammel and Lockwood apparently point out that this somehow supports their argument, but seemingly run right over the fact that this data shows nothing in regards to pre-1970 data, to which they use as part of their sourcing for data in TSI and on earth (but not Neptune).
And finally, one has to wonder how temperatures on Earth were even attempted to correlate with Neptune when solar radiance has decreased.
There is an increase in brightness on Neptune that we're noticing, but it very well may be due to the hemisphere we are observing on Neptune is experiencing its summer cycle, and the brightness could likely be the result of Neptune's very, very long seasons (compared to ours). What's more, most of the brightness that we're observing has occurred in very specific bands of latitude on Neptune. Again this paper points that out:
http://oposite.stsci.edu/pubinfo/pr/2003/17/paper.pdf
One has to wonder why Hammel and Lockwood apparently left out the idea of seasonal variation AS WELL AS the strong latitudinal variation.
So in summary, this is a horribly flawed argument constructed on a horribly flawed paper. The lesson to be learned is that peer-reviewed work, albeit the best source we can come up with for reliability, is most certainly not flawless. I've seen similar works slip through the cracks in other sciences such as evolutionary science, and some of my current works of study in exercise physiology and physical therapy rehabilitation. Shit happens. It's up to scientists to examine the work under scrutiny, mimic the research in question and test the data themselves to see if the results are similar. That is indeed what has occurred here, but much more often than not this task is performed or at the very least discussed to its logical end PRIOR to publication. It sucks when it seeps through the cracks like this, but it happens nonetheless.
___________________
Whence September dusk grows crisper still,
with leaves all crimson conquered,
I yearn to shout,
and dance about,
and stick pickles in my honker...
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