Story submitted by WUWT reader Nancy Green
There is a message in Marcott that I think many have missed. Marcott tells us almost nothing about how the past compares with today, because of the resolution problem. Marcott recognizes this in their FAQ. The probability function is specific to the resolution. Thus, you cannot infer the probability function for a high resolution series from a low resolution series, because you cannot infer a high resolution signal from a low resolution signal. The result is nonsense.
However, what Marcott does tell us is still very important and I hope the authors of Marcott et al will take the time to consider. The easiest way to explain is by analogy:
50 years ago astronomers searched extensively for planets around stars using lower resolution equipment. They found none and concluded that they were unlikely to find any at the existing resolution. However, some scientists and the press generalized this further to say there were unlikely to be planets around stars, because none had been found.
This is the argument that since we haven’t found 20th century equivalent spikes in low resolution paleo proxies, they are unlike to exist. However, this is a circular argument and it is why Marcott et al has gotten into trouble. It didn’t hold for planets and now we have evidence that it doesn’t hold for climate.
What astronomy found instead was that as we increased the resolution we found planets. Not just a few, but almost everywhere we looked. This is completely contrary to what the low resolution data told us and this example shows the problems with today’s thinking. You cannot use a low resolution series to infer anything reliable about a high resolution series.
However, the reverse is not true. What Marcott is showing is that in the high resolution proxies there is a temperature spike. This is equivalent to looking at the first star with high resolution equipment and finding planets. To find a planet on the first star tells us you are likely to find planets around many stars.
Thus, what Marcott is telling us is that we should expect to find a 20th century type spike in many high resolution paleo series. Rather than being an anomaly, the 20th century spike should appear in many places as we improve the resolution of the paleo temperature series. This is the message of Marcott and it is an important message that the researchers need to consider.
Marcott et al: You have just looked at your first star with high resolution equipment and found a planet. Are you then to conclude that since none of the other stars show planets at low resolution, that there are no planets around them? That is nonsense. The only conclusion you can reasonably make is that as you increase the resolution of other paleo proxies, you are more likely to find spikes in them as well.
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As a primer for this, our own “Charles the Moderator” submitted this low resolution Marcott proxy plot with the Jo Nova’s plot of the Vostok ice core proxy overlaid to match the time scale. Yes the vertical scales don’t match (numerically on the scales due to the ticks being different and the offset difference), but this image is solely for entertainment purposes in the context of this article, and does make the point visually.
Spikes anyone? – Anthony
![marcottvostok2[1]](http://wattsupwiththat.files.wordpress.com/2013/04/marcottvostok21.jpg?quality=83)
(Added) Study: Recent heat spike unlike anything in 11,000 years “Rapid” head spike unlike anything in 11,000 years. Research released Thursday in the journal Science uses fossils of tiny marine organisms to reconstruct global temperatures …. It shows how the globe for several thousands of years was cooling until an unprecedented reversal in the 20th century. — Seth Borenstein, The Associated Press, March 7th
Note: If somebody can point me to a comma delimited file of both the Marcott and Vostok datasets, I’d be happy to add a plot on a unified axis, or if you want to do one, leave a link to the finished image in comments using a service like Tinypic, Imageshack or Flickr. – Anthony
Thomas:
It would require writing a book to correct all your errors in your comments addressed to me in your post at April 4, 2013 at 12:37 pm. However, one of the difficulties results from a typing error which I made and failed to see.
I will quote each of your points in turn and give brief answers. And I will state my error which caused confusion.
It is not possible for me to prove a negative but it would be very simple for you to prove me wrong if I were. All you need to do is provide one single solitary piece of evidence that “that an increase to atmospheric CO2 from present levels will have any discernible effect on global temperature.”
You cannot provide such evidence because there is none.
Three decades of research conducted world-wide and costing over $5 billion p.a. has failed to find any. If you find some such evidence then publish it and get a Nobel Prize. Santer tried to pretend he had found some in the 1990s but his shenanigans was rapidly exposed.
I did NOT “assert” negative feedbacks.
I cited the evidence for negative feedbacks and I provided references and links to the pertinent papers.
SB derivation of climate sensitivity with no feedbacks is ~1 deg.C for a doubling of CO2 equivalent. The empirical measurements each provide indication of climate sensitivity which is about half that.
Quad Erat Demonstrandum.
The feedbacks are measured to be negative.
No! Clearly, you are as mystified by logic as you are by science.
This issue was explained to you by wte9 at April 4, 2013 at 11:45 am but you either did not read his explanation or have been incapable of understanding it. So, I will try to spell it out for you.
1.
Marcott provides a time series which cannot resolve ‘spikes’ similar to the recent global temperature rise because it lacks sufficient temporal resolution.
2.
The recent ‘spike’ is provided by the existing system.
3.
The Null Hypothesis says the system has to be assumed to be unchanged unless there is evidence of a change.
4.
Therefore, the Null Hypothesis provides a testable hypothesis which Nancy’s analogy explains; viz.
If the system has not changed then similar ‘spikes’ to the recent rise in global temperature would be observed in a time series with sufficient temporal resolution to observe therm.
Say what!?
I quoted you verbatim. You said
I fail to understand any possibility of that meaning other than you were claiming that correlation of those two parameters showed the system has changed (i.e. “Null Hypothesis fails”) and I don’t understand how that can be anything other than an assertion of causality.
That is such a mish-mash of illogical and untrue twaddle that I am tempted to let it stand because it defeats itself. However, it contains falsehoods so I will address those.
I did NOT try to “trivialize the observed warming”. There is no need to because it is trivial.
Over the twentieth century mean global temperature rose about 0.8 deg.C.
Each year mean global temperature rises by 3.8 deg.C deg.C from June to January and falls by 3.8 deg.C deg.C from January to June.
So, the warming which you want to exaggerate is about a fifth of the rise experienced during 6 months of each year.
Twaddle.
I pointed out – with example – the fallacy of ascribing cause without evidence and you claim ”science” says we should adopt that fallacy.
IT DOES NOT. SCIENCE SAYS WE SHOULD REJECT THE FALLACY.
I repeat, there is no evidence which uniquely identifies atmospheric CO2 concentration as being responsible for any of the recent rise in mean global temperature.
It seems you really do want to show you can bat 100% wrong.
If one wants to know how long it has been since there was any discernible global warming at 95% confidence then one has to start from now – any other date is ‘cherry picking’ – and consider back in time. Then one has to determine if global temperature trend differs from zero at the low confidence level of 95% which is used by ‘climate science’.
It turns out that – depending on which time series is analysed – the time of no recent discernible global warming at 95% confidence is between 16 and 23 years. In other words, discernible global warming stopped at least 16 years ago.
This finding refutes the AGW hypothesis as exemplified by global climate models.
The explanation for this is in IPCC AR4 (2007) Chapter 10.7 which can be read at
http://www.ipcc.ch/publications_and_data/ar4/wg1/en/ch10s10-7.html
It says there
In other words, it was expected that global temperature would rise at an average rate of “0.2°C per decade” over the first two decades of this century with half of this rise being due to atmospheric GHG emissions which were already in the system
This assertion of “committed warming” should have had large uncertainty because the Report was published in 2007 and there was then no indication of any global temperature rise over the previous 7 years. There has still not been any rise and we are now way past the half-way mark of the “first two decades of the 21st century”.
So, if this “committed warming” is to occur such as to provide a rise of 0.2°C per decade by 2020 then global temperature would need to rise over the next 7 years by about 0.4°C. And this assumes the “average” rise over the two decades is the difference between the temperatures at 2000 and 2020. If the average rise of each of the two decades is assumed to be the “average” (i.e. linear trend) over those two decades then global temperature now needs to rise before 2020 by more than it rose over the entire twentieth century. It only rose ~0.8°C over the entire twentieth century.
Simply, the “committed warming” has disappeared (perhaps it has eloped with Trenberth’s ‘missing heat’?).
I add that the disappearance of the “committed warming” is – of itself – sufficient to falsify the AGW hypothesis as emulated by climate models. If we reach 2020 without any detection of the “committed warming” then it will be 100% certain that all projections of global warming are complete bunkum.
Oh dear! Wrong again.
Perhaps CO2 did act as a positive feedback in geological times but – if it did – then
(a) that does not affect my point in any way
and
(b) that feedback was so small that it failed to stop temperature rising and falling because (according to the Vostock ice core) the delay of CO2 reversal was typically 800 years after each temperature reversal.
Also, that is the longest time scale and I said “at all time scales”.
At the shortest time scale CO2 follows temperature by 5 months. This was first discovered in 1990 by Kuo, Lindberg & Thomson
(ref. Cynthia Kuo, Craig Lindberg & David J. Thomson “Coherence established between atmospheric carbon dioxide and global temperature” Nature 343, 709 – 714 (22 February 1990) )
This has been independently confirmed by several others since and the subsequent studies have revealed that the time of the delay of CO2 after temperature varies with latitude.
Atmospheric CO2 was much higher than now throughout most of the time since the Earth has had an oxygen rich atmosphere. Indeed, plants grow better in higher atmospheric CO2 concentrations because they evolved when CO2 was higher. Horticulturists usually try to keep CO2 concentration in their greenhouses at ~1,000 ppm. Pumping CO2 into the greenhouses costs money but the obtained plant growth more than compensates for this cost.
Burning fossil fuels t is returning CO2 to the carbon cycle which was removed from the carbon cycle by the plants from which the fossil fuels were formed.
The Deccan Traps released CO2 in at least as great a rate as the burning of fossil fuels.
We know exactly what will happen if we return CO2 to the atmosphere: plant life and everything up the food chain from plants will gain the benefits which they had until the carbon was sequestered as fossil fuels.
I object to your misrepresentation of what I said. I cited the EMPIRICAL derivations of climate sensitivity. That is NOT bias. Choosing fiddle factors used in computer models over the empirical data is bias.
Ouch!
Thankyou I mistyped and failed to see my mistake.
I apologise for that error and thank you for pointing it out.
Having made the error I ‘read’ what I intended to type which was
“The feedbacks in the climate system are negative and, therefore, any effect of increased CO2 will be probably too small to discern because natural climate VARIABILITY is much, much larger.”
This was a clear typing error by me and demonstrates my poor ability at proof-reading my own words. I apologise for the resulting confusion.
We all make mistakes. It is important to acknowledge when we have made them. Perhaps you can try to do it, too?
Richard
dr. lumpus spookytooth, phd. says:
April 4, 2013 at 6:40 am
Leif I will give you this, you state more personal opinions than almost anyone.
Better than stating somebody else’s opinions, don’t you think?
Steve Keohane says: April 4, 2013 at 11:04 am
This is the Vostok graph I used to overlay on Marcott. It seems to show much more variation than the Vostok record record overlaid in red accompanying this article and Mike McMillan says:April 4, 2013 at 10:11 am.
Your version of Vostok has different year dates from the Jo Nova post. It has a 1999 before present date, while Jo Nova may have a different before present date. I’ll overlay the two and if there’s a noticeable difference I’ll redo.
Your analogy is very very useful and of course covers vast other discussions, from history, to crime, to well, everything. In short, ‘absence of evidence is not evidence of absence’.
I must nitpick the planet discovery thing though, “as we increased the resolution we found planets” unless we confine that statement only to our own solar system. The current trend at NASA and other places is to pronounce every “wobble” or “dimming” as a new planet, and they build up a ledger of names of “discoverers” of new planets, people who deserve no such recognition, yet.
We don’t even have adequate optical resolution photos of the “nearby” planet Pluto and her moons in my opinion, and those newer ones beyond her that are still “nearby”. These so-called “planets” in other solar systems are hundreds and thousands of light years away (while Pluto is like .0005 on average) which is tens and hundreds of million times farther away. They can show me a picture when they got one. 🙂
This is extra-solar planet thing is all about “safe Science”, stuff that cannot be proven in the next thousand human lifetimes, and is merely a way to get recognition and funding for doing nothing of consequence. Wikipedia proves this by saying “A total of 861 such planets (in 677 planetary systems, including 128 multiple planetary systems) have been identified as of March 22, 2013”. Utter garbage. Defund this nonsense. And stop naming planets in far-away places that may already be named by the local inhabitants 😉
P.S. this is not a religious statement, it is not an attack on “Science”, it is an attack on lack of precision and fake work which should not be called “Science” at all, just like the entire AGW hoax. I don’t need fake Science to tell me there are planets everywhere. I already know they are there from glancing up at the stars.
Personally I prefer a little more accuracy in my blanket statements. Using “warm the planet” in this sentence sure sounds like adding heat were there was none before. Precision demands that statement to instead read as ‘slows down the loss of heat’. That may sound like nitpicking, and certainly would be for the average layman, but that does not include Steve Mosher.
I can think of one scenario where CO2 would add heat where none existed before. Imagine an experimental planet with zero atmosphere, a complete vacuum. Now we add an atmosphere of pure CO2. Now, completely disregarding the “greenhouse effect” of capturing and re-emitting some IR back towards the planet, in fact just imagine there is no sun and no incoming radiation at all. Summary: there is “new heat” by way of friction of atmosphere molecules now bouncing off things, i.e., matter exists where previously there was none. Is this added heat even measurable? Probably not, just ask the Martians whose planet is an example of that experiment.
The point is Mosher, that phrase sure sounds to me like you are saying adding CO2 adds heat, but in reality the effect is only fractionally slowing down cooling. The existing heat is exactly the same heat that was always going to be there, minus the heat from friction of extra air molecules. Steve knows this full well, yet he continues to parrot the phrase “CO2 will warm the planet”. He apparently does not give a crap that he is misleading the people that do not follow these things closely. Why is that, Steve?
Here’s another analogy.
Let’s say that I plotted the average daily temperature for September 1 through September 30.
Then on October 1, I plotted the average hourly temperature from 7:00am until 2:00pm.
Could I then claim that there’s a never before seen temperature spike occurring?
Thomas says:
April 4, 2013 at 12:37 pm
” CO2 has continued to rise while global temperature has NOT risen for at least the last 16 years.”
Actually we do have a positive trend over 16 years,
It depends on your data set. For RSS, for example, the slope since December 1996 to March, 2013, is -2.3524e-05 per year. This is 16 years and 4 months. See:
http://www.woodfortrees.org/plot/rss/from:1996.9/plot/rss/from:1996.9/trend
Actually, let me change the times to 11:00am to 3:00pm.
Thomas says:
April 4, 2013 at 12:37 pm
‘“To falsify the Null Hypothesis, which is what you want to do, you must show that the warming in the last 100 years cannot be explained by natural fluctuations.”
Now, this is a fundamental misunderstanding of how science works. You can *never* prove that something can’t be caused by some unknown process. Maybe gravity doesn’t exist and it’s just angels pushing the planets around. How do you disprove that? In science you create different hypothesis how something works, calculate what predictions they make, and make measurements to see which hypothesis works best. It may not be perfect, but until you find something better you work with the theory you have, trying to find the boundaries for where it is useful.’
The full range of natural variation is found in the historical records. The highest temperature is the top of the range and the lowest is the bottom of the range. If present temperatures exceed the highest historical temperature then we have something to explain, namely, what caused the high range of natural variation to be exceeded. The Roman Warm Period exceeded today’s temperatures and the Medieval Warm Period equaled them. Therefore, there is no reason to assert that natural variation cannot account for today’s temperatures.
Some Alarmists argue that the rate of temperature increase since 1975 or so has been greater than any known rate. Setting aside matters of cherry picking, the rate of increase in the Thirties was as high as the rate today. In any case, to make the argument you have to buy into Mann’s preposterous Hockey Stick. If you have bought into Mann’s work, you simply have not done your homework.
Do you now understand what natural variation is? It is simply the full range, bottom to top, of temperatures known from historic records and paleo studies and such. If present temperatures fall within that range then natural variation explains present temperatures. (Yes, climate scientists should be hard at work identifying all causes of historic variation but they seem unable to do that while publishing CAGW warnings brings in the grant dough.) If present temperatures were to fall outside the range in a non-trivial way, then the Null Hypothesis would be falsified and there would be a reason to search for a cause that is unique to our time, something like manmade CO2.
You, like most Alarmists, labor under the confusion that climate science is about causes only. Alarmists present manmade CO2 as a cause of higher temperatures, though they will not admit that no such thing can be known until the “forcings and feedbacks” calculation is complete, and challenge Skeptics to come up with a better cause. That is not science because it ignores the records of observations that define the higher and lower bounds of what can be expected from natural variation.
@ur momisugly Thomas says:
April 4, 2013 at 12:37 pm
markx “Are stating here that you consider the 20th century temperature spike is ‘proven’ because you know CO2 levels have risen? ”
No, I consider it proven because we have observed it.
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LOL you get props for being persistent. Well done!
Yes, sort of. But you’ve no idea how it relates to the past. No one does. And that’s the whole point of the discussion about resolution.
As to CO2 being the cause, repeating a mantra doesn’t make it true. As you correctly pointed out, there’s probably thousands of estimations of climate sensitivity to CO2. They’re all over the board. No one knows what it is or even if there is a measurable sensitivity. Forgoing rehashing of old arguments like the ignoring of other heat transfer mechanisms, and absorption frequency windows, we can just say there is no skill in such calculations because we don’t know how a chaotic system is going to work. It’s the ultimate hubris to believe otherwise.
As to the null hypothesis, you don’t know what else could cause a spike, ergo none exists? The problem arises when people feel an explanation is needed when no need really exists. There’s plenty of evidence the current warmth isn’t unusual. But, you’re focused on a spike which can’t be seen in the paleo recons because of the resolutions. So, it must be CO2. Sadly, I think this is how much of the climate science is conducted today.
As to the warming over 16 years, I’m sure you know it depends on what temp set one uses. http://www.woodfortrees.org/plot/rss/from:1997/plot/rss/from:1997/trend Of course, if we use that, it pokes some holes in the whole thought experiment about CO2. Sat temps are suppose to be amplified. oops. Ignore that inconvenience. We can conceive of nothing else, ergo, we’re right.
As far as negative feedbacks….. they are published in all sorts of science literature. Indeed, we just read a paper asserting the warmth is the cause for the expansion of the southern hemisphere ice extent. We’ve also seen insistent claims about the warmth causing the cold and snow. Now, I’m not big on the warmcold theory, but it is out there, promoted by alarmist sciency types. Still, we can’t help but notice the expansion of the ice and the increase in the winter snow. If we are to believe calculations regarding albedo, I’d say we’ve found a couple of negative feedbacks, and because of the origins of snow, it seems we’ve probably found another.
I’d go on but I don’t wish to deprive anyone of their fun.
Thomas says:
April 4, 2013 at 12:37 pm
“Now you are being silly. Surely you are aware that we have had good scientific reasons to believe CO2 causes warming for well over a century. It’s not a matter of what I want but of what existing science tells us.”
You continue to assert this point though people have explained that the “forcings and feedbacks” calculation is not complete. We cannot know that manmade CO2 causes increases in global average temperature until that calculation is complete. It does not matter what CO2 does in the laboratory. What we need to know is what it does in the atmosphere. No one will know until the matter of forcings and feedbacks has been sorted out.
I conclude that you have no idea what the “forcings and feedbacks” calculation is.
Nicely put Ms Green.
Previous statements that exaggerate expertise and hide ignorance are:-
“We only use 10% of our brain”
“Most DNA is junk DNA”
richardscourtney says:
April 4, 2013 at 2:35 pm
————–
As usual a pleasure reading your rebuttals Richard, well done as always, except for the frustration I experience due to your thoroughness. Once you’ve finished posting there isn’t any troll leftover for me. 🙂
Steve Keohane says: April 4, 2013 at 11:04 am
This is the Vostok graph I used to overlay on Marcott. It seems to show much more variation than the Vostok record record overlaid in red accompanying this article and Mike McMillan says:April 4, 2013 at 10:11 am.
The two curves are identical..
Mark Bofill:
Thankyou for your post addressed to me at April 4, 2013 at 3:49 pm.
I apologise for my “thoroughness” but I only answered points addressed specifically to me. Others (e.g. Theo Goodwin) have also addressed some of those same points.
If I thought my contributions were to prevent your making your much more succinct and extremely cogent posts then I would cease to contribute.
At April 4, 2013 at 2:32 pm, my son provides a demonstration of how to make a clear and complete argument in far fewer words than I do .
I console myself with the hope that a variety of onlookers will contain a variety of types of people so a variety of types of post will be appreciated. Different people liked information to be provided in different ways.
Richard
lsvalgaard says:
Better than stating somebody else’s opinions, don’t you think?
Since most opinions on AGW are appropriated from others with no value added and often with no understanding of any science behind those opinions, the climate discussions in the blogs and media would be rather shorter without all that repetition.
Toto:
In your post at April 4, 2013 at 4:48 pm you assert
The only way I can make sense of your assertion is to assume that by “blogs” you were talking about warmunist ‘echo chambers’ such as SkS.
It is certainly not true of WUWT as anybody reading e.g. this thread can see.
Richard
richardscourtney says:
April 4, 2013 at 4:34 pm
“Mark Bofill:”
Thanks for your dedicated work in behalf of science. You do a good job, too, Mark.
Nancy Green,
Thanks for this excellent article. Marcott is not getting much traction in the media.
I’m dedicating this post to Thomas and all the other wacky head of a pin tapdancers from the last week that I’ve seen here, on Climate Etc. on Pielke Jr’s, at Climate Audit and at Revkins place.
A Josh cartoon from almost a year ago.
http://wattsupwiththat.files.wordpress.com/2012/04/expert_opinion.jpg
And an excellent read from Robert Tracinski which has my quote of the day.
http://www.realclearpolitics.com/articles/2013/04/04/the_end_of_an_illusion_117795.html
“A theory with this many holes in it would be have been thrown out long ago, if not for the fact that it conveniently serves the political function of indicting fossil fuels as a planet-destroying evil and allowing radical environmentalists to put a modern, scientific face on their primitivist crusade to shut down industrial civilization.
But can’t we all just stop calling this “science” now?”
richardscourtney says:
April 4, 2013 at 9:15 am
=====================
Bravo Richard for that wonderful and concise explanation of the null hypothesis.
The frustration must be hard to take when someone is just incapable of being educated.
The common theme here, as ever, is an inability to put the results before the conclusion.
Skiphil says:
April 3, 2013 at 8:29 pm
fyi, Tamino has a new post claiming to have tested via “three spikes”
==========
My understanding is that Tamino has drawn in 3 spikes on top of the old proxies data and voila, Marcott can detect them. I’ve been hearing that RC and Tamino have become quite excited since I posted this paper to their sites!!
What you have to realize is that Tamino has played a magician’s trick on you. He hasn’t added the spikes to the location where the proxies were created, he has drawn them on top of the proxy data. To understand this by analogy, consider this:
Adding additional planets around stars does not make them detectable to astronomers 50 years ago. These additional planets would be real spikes. However, drawing picture of planets on the old photos will certainly make them detectable! These are Tamino’s spikes. Your half blind old granny could detect them!! So, no surprise Marcott was able to do the same.
I would like to thank the many contributors that have made this the Top Post at WUWT. Wahoo! Please pat yourselves on the back. I would especially like to thank Anthony and “Charles the Moderator” for helping make this article such a success.
<i. Mike McMillan says:April 4, 2013 at 4:21 pm
~Steve Keohane says: April 4, 2013 at 11:04 am
~This is the Vostok graph I used to overlay on Marcott. It seems to show much more variation ~than the Vostok record record overlaid in red accompanying this article and Mike McMillan ~says:April 4, 2013 at 10:11 am.
The two curves are identical..
My proxy graph, linked above has 25% more variation, not counting the initial tail. It measured readings from -2°C to +2°C in the past 8100 years as opposed to -1.3°C to +1.87°C from the graph you used.
Graphically: http://i48.tinypic.com/2v8k11s.jpg
When an analog time-waveform is processed on a digital computer (as opposed to processed on an analog computer–which in today’s world, is a rare event), the original analog signal must have been sampled at discrete time intervals. An ideal low pass filter (a) passes undistorted (constant gain–ideally unity, and either no phase shift at any frequency or a phase shift at each frequency that is directly proportional to the frequency) all frequency components in the signal below the filter cutoff frequency and (b) completely removes all frequency components greater than the filter cutoff frequency. The impulse response (both digital and analog) of an ideal low pass filter is a sync function (continuous in the analog case, discrete time in the digital case) that in time extends to plus and minus infinity. As such, in the real world ideal low pass filters don’t exist. If the original analog signal is sampled at uniformly spaced time intervals, then the discipline of digital signal processing can be used to characterize filter performance. If the original analog signal is sampled at nonuniformly spaced time intervals, then most uniform-time-sampled-data digital signal processing “rules” cease to apply. For a real analog signal (as opposed to a complex analog signal), uniform sampling aliases (causes frequency information to appear at a different frequency) all signal frequency information above half the sampling rate into signal information in the frequency interval between 0 and half the sampling rate. If frequency components above half the sampling rate exist in the analog signal, the uniform-rate sampling process renders recovery of analog frequency information above half the sampling rate impossible and corrupts the analog information below half the sampling rate.
For uniform sampling, a moving average corresponds to an impulse response that is zero everywhere except over a short, finite, continuous time interval, during which the impulse response is constant. A moving average impulse response acts like a poor low pass filter. Specifically, except at discrete frequencies, some high-frequency information is passed, and the gain as a function of frequency over low frequencies is not constant. The degree to which these imperfections affect conclusions drawn from uniform-sampled, low-pass filtered data will in large part be a function of the original analog signal and the information being sought.