Tuesday, June 27, 2017

Rant on climate change

Warning: this is a rant. A friend of mine recently posted on Facebook a link to an unscientific article about climate change which rather annoyed me.


When I call the article unscientific, I don't mean that "it challenges the commonly accepted ideas about climate change". Challenging accepted ideas is at the very core of true Science (with a capital S). What I mean is that this so-called "challenge" does not follow the basic rules for Science, for science reporting, or for journalism in general. It follows the rules of propaganda. 

The article in a purported news outlet is based on an article in a second news outlet, which was in turn based on an article in a third news outlet. This house of cards was ultimately built on a blog post. The original blogger is either utterly stupid, or a deceitful, shameless charlatan who has pledged mindless allegiance to the climate change deniers club. Either way, his blog post is complete garbage. But of course, you wouldn't know that if you just read the first news article that my friend posted.

If there are valid scientific arguments against climate change exist, this is clearly not one of them. 

New scientific study

The link was to an article in Federalist Papers.

Let's start with the alarmist title: "New Scientific Study Demolishes Liberal Climate Change Arguments". The rhetoric is a bit distasteful. It is rather unlikely that a single paper could "demolish" the conclusions of 3,894 peer-reviewed journal papers. And climate change is not a liberal thing. It's a science. People who disagree with climate change are allowed into the club, so long as they agree to follow the basic tenets of Science

But... rather than quibble about rhetoric... If the purpose of the Federalist Papers article is to present Science, they would post a link to the paper, or at the very least, properly cite the article by giving the title, authors, and where it was published. Where is this new study? The article only provides us with two sources, neither of which is to a scientific article. Both are links to Daily Wire -- not to a reputable peer-reviewed science journal. 

The Federalist Papers article claims that the study is the "most recent findings from the Danish Meteorological Institute (DMI)". This contradicts the Daily Wire article that they cite. Here is a quote from the the Daily Wire article: "The Telegraph newspaper in the UK has published a fascinating article detailing data from the Danish Meteorological Institute (DMI)." The new scientific study is not from the DMI, but derived from data from the DMI. 

Ok... my skeptic flag is going off. There seems to be  pattern of deception here; is this an attempt to make the new scientific study appear more significant than it is? If a reputable organization that should be full of climate change zealots says that climate change is a hoax, well gosh darn it, that's compelling. We shall see just how significant the "new scientific study" really is.

The Daily Wire article in turn, gives a link to an article in Telegraph. This article cites a blog post from Paul Homewood, who provides his terse commentary on six graphs from DMI. Six graphs and 147 words of careful, detailed scientific explanation. (Note: when I said "detailed scientific explanation", I was being sarcastic. I dunno if that was clear.)

Ok... so let's count. The article from the Federalist Papers cites Daily Wire, which cites Telegraph, which cites a blog, which cites DMI. We have a fourth-hand account of DMI data, with the conclusions largely drawn from a blog which is called a "scientific study". Fourth hand reporting of uncited sources is bad journalism, and as we all know, playing telephone with the Telegraph generally leads to misinterpretation.

So, even without researching the claims in the blog, this is just plain sloppy journalism.

The mean temperature of the Earth

The original Federalist Papers article starts with a meme that claims the Earth's mean temperature is unchanged between 1996 and 2016. The meme does not cite the source of this information. Again, very, very sloppy journalism.

Is this true? I did a little fact checking. Here is a chart from NASA.



"With the contribution of eight consecutive high monthly temperature records set from January to August, and the remainder of the months ranking among their five warmest, 2016 became the warmest year in NOAA's 137-year series."

Here's a blog post that deeply investigates that meme. I quote the conclusion of the blog post:

"So in summary, whoever made up that meme 1) lied about their numbers, 2) is ignorant of the actual temperature data, and 3) abjectly ignorant of basic statistical concepts.  And then they had the balls to call Al Gore and progressives liars.  How quaint."

So, you have the choice between believing a meme that offers absolutely nothing to back it up and actual data from NASA and NOAA. I heartily welcome a legitimate critical look at the data and analysis from these organizations, but the meme is an insult to my meager intelligence.

In my book, the fact that Federalist Papers included that meme is a huge discredit to the article, and puts the whole website in a bad light. Note: While most of the Federalist Papers article was based on the Daily Wire article, the stupid meme was brought in by Federalist Papers.


Quotes from the Telegraph

After the meme, the Federalist Papers article gives a quote which it says is from  Telegraph. (I assume that the quotes did actually come from the Telegraph article. I tried to look at this article, but it was behind a paywall.) I will analyze the claims in this quote one at a time.

"Ever since December temperatures in the Arctic have consistently been lower than minus 20 C." 

This is a factual statement, and could be deduced from the original data from DMI.

However, DMI cautions about the interpretation of this data. (The bolding is my own, to call note to the warning. The capital letters on "NOT" are from the original.)

"The temperature graphs are made from numerical weather prediction (NWP) "analysis" data. Analyses are the model fields used to start NWP models. They represent the statistically most likely state of the atmosphere, given the information available to make the analysis. Since the data are gridded, it is straight forward to deduce the average temperature North of 80 degree North. However, since the model is gridded in a regular 0.5 degree grid, the mean temperature values are strongly biased towards the temperature in the most northern part of the Arctic! Therefore, do NOT use this measure as an actual physical mean temperature of the arctic. The 'plus 80 North mean temperature' graphs can be used for comparing one year to an other."

Even if Telegraph was making proper use of the data, the statement does nothing to refute climate change. What was the typical temperatures during this part of the year ten or twenty or forty years ago?

The Federalist Papers article stops there in summarizing Homewood's blog. The blog goes on to say that the Arctic temperatures "are currently below average".

Here is the plot, taken from Homewood's blog post (which came from the DMI website), which he uses to support this statement. The green line is the average temperature, and the red, jagged line represents the temperatures from 2017.


Ummm.... I may not be so good at math and stuff, but the red line appears to me to be almost entirely above the green line. Homewood has either made an honest mistake, or he is deliberately misinterpreting this graph to support the climate change denier narrative. I think this statement might not get past peer review in a real scientific article.


"In April the extent of Arctic sea ice was back to where it was in April 13 years ago."

This is based on the following comment from Homewood's blog: "Average April ice extent has now been stable since 2004."


Here is a closeup of the last 18 years from this chart, with a horizontal line in green so we can compare. To me, it looks like you could legitimately make the statement that the April ice extent is very close to what it was 11 years ago, but that's a misrepresentation of all the available data. All real-life data has variability, so you need to do some stats on the trend. Our good friends at DMI did the stats, came up with a regression line (in black), and concluded that the ice extent has been shrinking by 2.8% per decade. That's how Science is done.


Homewood has resorted to egregiously cherry picking data. That's how Propaganda is done. 


"Furthermore, whereas in 2008 most of the ice was extremely thin, this year most has been at least two metres thick." 

The quote from Telegraph is consistent with Homewood's terse analysis. This analysis is based on his subjective summary of the following two maps. For convenience, I combined the two into one image and put them side-by-side.


My own subjective analysis is two-part. First, I have to agree with his assessment that there is a lot of healthy green and yellow in the 2017 map of the area around the North Pole -- more so than in 2008. Santa will be happy to hear that, but this is subjective. More importantly, I have to ask myself why Homewood chose 2008 as the year to compare against. I had a peek at DMIs map from 2007. This would clearly be a bad map for a climate change denier to compare against, since it would not support the narrative. Once again, Homewood has cherry-picked data with a lot of variability. Bad Science. 
  
The second part of my subjective analysis is that the map on the right has a whole lot more purple than that on the left, particularity on the right side of the map. Purple represents ice that is less than a meter thick. This is alarming. This is the thinnest and hence the most precarious area. Since the transition between water and ice at 32 degrees involves a lot of energy exchange, I would guess that if this ice cover is lost, it will be hard to regain.

Now for the objective analysis. Homewood has conveniently ignored the graphs in the upper-right hand corner of the images which compare the ice volumes over multiple years. I expand them and show the two below.


The gray swath on both graphs is the average of the years 2004 and 2013. The width of the gray swath is 2 standard deviation units. Under the assumption of normal statistical variation, we would expect that data would fall in this range about 95% of the time.

Note from the graph on the left that 2008 hugs the edge of the gray swath. (The 2008 data is the dark black line.) This demonstrates that 2008 was an anomalous year, with exceptionally low ice volume. Hint to cherry-pickers: This would be a great year to compare against, since it is not very representative of the typical year between 2004 and 2013. 

More importantly, note the graph on the right which shows that 2017 (and 2016, for that matter) are both well below the gray swath. This is clear evidence that the 2017 and 2016 data is not just a statistical anomaly. This is real. There has been a statistically significant reduction in Arctic ice volume when you compare 2016 and 2017 to the time period from 2004 to 2013.

Homewood's statements are refuted by the very graphs he submits as evidence.


"The Greenland ice cap last winter increased in volume faster than at any time for years."

This is directly from Homewood. He provides a graph from DMI to support this, but really only states his conclusion. The graph all by itself is hard to make sense of, since none of the axes are labelled. 

But from reading the actual webpage on DMI, this statement is mostly factual, but misleading. Snow accumulates during the winter and large pieces of ice break off into the ocean (called calving) in the summer. Homewood has looked at the accumulation part, and in just one year.



Quoting from the DMI website:

"Over the year, it snows more than it melts, but calving of icebergs also adds to the total mass budget of the ice sheet. Satellite observations over the last decade show that the ice sheet is not in balance. The calving loss is greater than the gain from surface mass balance, and Greenland is losing mass at about 200 Gt/yr."

(A Gt is a gigaton, one billion tons. The yearly loss of 200 Gt amounts to a block of ice that is about 6 kilometers by 6 kilometers by 6 kilometers.)

Ok, so, I have been loosing money in the stock market practically every year for like 36 years... and this year (so far) I'm doing better than other years. Maybe I will wind up with a net loss at the end of the year, but I dunno yet. Ummm... should stay in the stock market?


"As for those record temperatures brought in 2016 by an exceptionally strong El Niño, the satellites now show that in recent months global temperatures have plummeted by more that 0.6 degrees: just as happened 17 years ago after a similarly strong El Niño had also made 1998 the “hottest year on record”."

This is the final part of the quote in the Federalist Papers / Daily Wire quote from Telegraph. I don't know where this came from. It is not in the blog post by Homewood. Clearly it was not derived from actual data from NOAA. The graph below compares global temperatures of 2017 against the eight warmest years on record. I don't see a 0.6 degree plummet. I see something more like 0.2 degrees.


But clearly, 2017 is starting out with lower temperatures than 2016, so although his point is exaggerated by a factor of three, the good news holds -- this year has (so far) been cooler than last year. But before we get out the party hats and champagne, the bad news is that 2017 is on track to be the second warmest year since 1880. And by the way, the eight warmest years in the 137 year record were 2016, 2015, 2014, 2010, 2013, 2005, 2009, and 1998 -- all of which are in the last two decades. 

Conclusion

The direct conclusion is that the blog that all this is based on is complete trash, and the subsequent articles in Telegraph, Daily Wire, and Federalist Papers are lazy and irresponsible.

One would be tempted to make some generalizations here. I want to make it clear that I am not arguing in favor of the generalizations.

First, one may think that I am saying that, since this particular sequence of webpages is poppycock, the entire climate change theory must be correct. This would be poor reasoning. Strong evidence against climate change may exist, but this is definitely not it!

On the other hand, the data and papers from DMI, NOAA, and NASA that are mentioned here provide some pretty clear evidence that climate change is real. I welcome any cogent analysis that proves otherwise.

Second, one may think that I am saying that the three news sources mentioned are unadulterated BS. Again... poor reasoning. I would definitely argue that, based on his atrocious blog, Paul Homewood has demonstrated that he has no business writing about science. But, while the articles in the news sources are downright sloppy journalism that appears to be propaganda, my only conclusion is only that these websites should be read with skepticism. As should all news sources...

Monday, June 19, 2017

Just for laughs

Today I share some of the most brilliant memes ever created. Well... some of the most brilliant memes that I have created.

Playing with my food






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For my Jewish friends



When food is love (and we are promiscuous)




And speaking of sleep



Tuesday, May 16, 2017

What is the opposite of yellow?

There is a controversy about complementary colors!
Will the most complimentary color please stand up!

I watched an interesting YouTube video the other day that answered the question that has been foremost in the hearts and minds of Americans these days: "Why Are So Many Popular Cartoon Characters YELLOW?"


Channel Frederator (that's the name of the guy in the video, or something like that) gave a very entertaining answer to this question. I won't spoil it for you. I will let you watch the video to find the answer.

The complement of yellow is purple

I want to zoom in on the explanation of complementary colors. Frederator first showed the artist's color wheel. This wheel is designed around the color system that I learned about in kindergarten... when I wasn't chasing Tammy around the playground. 

The artist's color system is based on the set of artist's primaries: red, blue, and yellow. Someday, I will write a blog post that totally destroys this silly notion about this silly set of primaries, but for the time being, let's just accept these as a hymn from the gospel choir with shouts of Alleluia! coming from the congregation. Here is an actual screenshot from the video, defaced with some childish scrawling from me.


Artist's color wheel, showing purple opposite yellow

So, yellow's complementary color on this wheel is purple. Or, to put it in the words of Frederator, "So, yellow's complementary color on this wheel is purple." (At the 2:45 mark in the video.)

The complement of yellow is blue

Now the controversy starts. Frederator then describes a second color wheel, based on another set of color primaries. In this view of the colorverse, the complement of yellow is blue! This is just too much for my simplistic brain to hang on to!!


RGB color wheel, showing blue opposite yellow

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The complement of yellow is purple blue

I wish it stopped there. Albert Munsell, the father of Color Science, developed his own color system something over 100 years ago. His color system is three-dimensional, however the following image shows just a slice of it. The illustration below is unrepentantly stolen from the Munsell website. Again, I scribbled on it with my Photoshop equivalent to crayons.

Munsell color wheel

In the Munsell system, the complement to yellow, which Munsell euphoniously named Y. The complement of Y was neither purple nor blue, but PB. I am not sure whether PB stands for peanut butter or purple-blue. I will have to ask him next time I bump into him.

You might say that Munsell found a compromise between these two warring factions. That might not have been his reason for spending the majority of his adult life researching color and inventing the Munsell Color Tree, but this is indeed a compromise. My wife tells me that she knew this all along. The complement of yellow is either blue or lavender / purple. I wish she woulda told me before I wasted all that time on the blog!

The complement of yellow is blue

Now, let's get into some more recent science. Munsell did some scientifical stuff -- I am not suggesting otherwise -- but there has been some progress in organizing crayons since then. Here is an attractive diagram that shows a color wheel based on the CIELAB color space.

Dieser CIELAB-Farbkreis zeigt für ΔHue=10 die jeweils
in CMYK erreichbare höchste Chromazität.

I need to back up just a bit. The CIELAB color space became an official standard in 1976. It is based on a long line of work that started with Munsell, but included the work of many luminaries in the field of color: MacAdams, Adams, Nickerson, Hunter, and Glasser. From a qualitative standpoint, the CIELAB color space looks a great deal like the Munsell color space. Today, CIELAB is defined in the ISO standard CIE 15:2004, and has been chosen as the official color space of the 2018 Olympics. So, it is considered good science.

From a casual glance at the preceding diagram (the one with the German caption which I clearly never bothered to translate), it's apparent that the color directly opposite yellow is a shade of blue. It would seem that Munsell's compromise got lost somewhere.

But, I am cautious in drawing this conclusion. First, the diagram looks real slick, but how do I know that it's correct? This is especially important since the interpretation of RGB colors in an image is up for interpretation. Without a color managed workflow, we can't know that the color that shows up on my computer monitor is the same as the one that showed up on the computer monitor of the person who created that slick graphic. To add to the ambiguity, who's to say that my perception of blue is correct? My wife would certainly argue otherwise. Call her up. She would be glad to tell you that I am wrong about virtually everything.

(Comment from my wife: Except for the fact that I was right to marry her--she's actually quite ecstatic about that.)

I just happen to have a previous blog post about color naming that could provide a more meaningful answer. In this blog post, I congealed a bunch of data about the CIELAB values of a variety of fundamental colors. I repeat the fabulous diagram below.

The fabulous diagram that was referred to in the text

Based on the above diagram, which gives CIELAB ranges for some basic color names, the CIELAB answer to the question of what is the complement of  yellow is blue. 

So, what-people-would-call-blue is the complement of what-people-would-call-yellow

Did I say purple blue? I meant blue

Did Munsell really mean "purple blue"?

There is something of a bridge that connects the Munsell color space to CIELAB. This bridge is called the Munsell Renotation Data. This is a table of 2,729 colors, where each color is expressed using the Munsell notation and in CIELAB values. These values can be used to test whether the Munsell and the CIELAB answers to the question of complementary colors are consistent.

I selected all the entries in the renotation data that have a hue of 5Y. This hue designation is in the center of the yellow group of hues. They have an average CIELAB hue value of 98.3. There was a bit of variation, so I also looked at just the most saturated colors in the 5Y family. If I select only those colors of high chroma, the average CIELAB hue is 93.7. Where does this put the complement? These hue values are in degrees, so this would put the complement of yellow at a CIELAB hue of -81.7 or -86.2. I did the same computation for the PB5 section of the table. I got CIELAB hues of -86.8 and -82.2.

My conclusion is that Munsell and CIELAB are basically in agreement as to the complement of yellow. It's blue, ok? The only odd thing is that Munsell seemed to think that it should be called purple blue. Something else I need to talk with him about the next time we have a beer together.

The complement of yellow is yet to be decided

Ok... how about two more approaches to answering the question? Both start with another question.

Q: What is the complement of yellow?

A: What do you mean by "complement"?

Why didn't I think before to question the question? 

One answer to the second question is that complementary colors means that the two colors look good together. That's a kinda fuzzy definition. How can I make that definition a bit more solid?

I could perform a huge psychometric experiment to answer this question. I would recruit a bunch of volunteers and ask them to tell me which of the three colors below (purple, purple blue, or blue) go better with the yellow. 

Which shade goes better with yellow?

So I'm recruiting you. Since you made it this far in the blog post, I assume you may actually have an interest in the topic. Which of the three shades go better with yellow? Answer in the comments below. (Note that I moderate the comments, since there is a fair amount of spam. Please don't get upset if your vote doesn't show up for a day or two.) I readily admit that the answer likely depends on the characteristics of your computer monitor and viewing conditions, but... baby steps.

The complement of yellow is bluish purple blue

I present another answer to the secondary question about what complementary color means. But first let me show you an optical illusion I just created. I'm pretty excited about it, so I just had to show someone.

Please take a moment to find the star in the image below. Once you have identified the star, please find the black dot within the star. Stare at the black dot in the middle of the star for ten or twenty seconds, and then look at one of the other three black dots. I find this works best with the room lights darkened, with a glass of a full-bodied red wine in hand, and with some Gato Barbieri playing softly in the background. The presence of a full-bodied person of your prefered gender is recommended, but not required.


When you avert your eyes to one of the other dots, you will see an afterimage of the yellow star, but it won't be yellow anymore. I added some white space below the black dot so you can better assess the color of the afterimage, and to compare it to one of the three afterimage colors. It will likely come close to matching the hue of one of the three background colors. For me, the afterimage star was somewhere between the hue of the purple blue and the blue background.

For my wife, the experience was a little different. She says: Doesn’t the color of the star vary depending on which background color you look at? When I looked at purple it was slightly darker than the purple and when I looked at blue it was slightly darker than the blue. Just saying. 

She's right, but she missed something really subtle in what I said. I used the word hue, and not color. In my silly little manner, I just assumed that everyone would know that I was talking about the more technical definition of hue, which is roughly speaking, the position on the color wheel. Pink, red, and brick red are different colors but have more or less the same hue.

Now try a variation on this. Take another sip of the Malbec, and stare at the star for another ten or twenty seconds. Then avert your eye slightly to look at one of the tips of the star. The purple or blue afterimage star will follow your eye for a moment, until it fades. Hang onto this thought while I transition into the next section.

Seymour's hypothesis of complementary colors

Here's my own explanation for the phenomena of complementary colors. Maybe this explanation has been articulated elsewhere - I don't know. It didn't occur to me until I was writing this blog post. If one of my readers has seen this explanation somewhere else, I would be happy to hear about it.

Thomas the Tank Engine demonstrates saccades

Our eyes are always moving around, even when we are not consciously moving them. This is known as saccades. Because of saccades, we are always seeing these afterimages. Generally, we are not consciously aware of them, but I hypothesize that they may interfere with our perception of adjacent colors. If the afterimage has a significantly different hue than the adjacent object underneath, then the edges of an adjacent object will change hue whenever our eye wiggles around. 

This constantly shifting hue will subliminally interfere with our ability to parse out the various parts of the image. If the afterimage has more or less the same hue as adjacent colors, then there is no interference, and we see harmony.

That's my hypothesis, anyway. I welcome comments, unless the comments are negative.

What causes an afterimage?

(Warning: The following material contains references to scientifical stuff, and hence may not be suitable for all readers.)

Now for the psychofizziks behind the afterimage effect. 

When we see something, photons are captured by photoreceptors in the eye, putting the photoreceptor cells in an excited state. The excitement in the cells triggers a reaction that results in a nerve impulse. I see the light! But, photoreceptors being what they are, it takes a little while for them to settle back down. They sit out on the sidelines for a bit before getting ready to capture the next photon.

A wideband photoreceiver who can't wait to get back into the game

BTW - I used a football analogy to explain what the photoreceptor is doing. In actuality, though, the analogy (much like everything else about football) is exactly backwards. The photoreceptor doesn't sit on the sidelines to recharge, but rather to discharge. Catching the photon gave it more energy, and that energy has to be dissipated before the next cycle can begin.

When a single photoreceptor is on the sidelines, we can still see because there are plenty other neighboring photoreceptors to catch photons. But each photoreceptor that is sitting out increases the probability that a photon can pass unnoticed. So, as more and more photoreceptors are sitting on the sidelines (i.e. when there is a lot of light), the eye becomes relatively less sensitive to photons.

This effect happens independently for the L, M, and S photoreceptors. (These represent the long, medium, and short wavelength cones in the eye, roughly relating to red, green, and blue light.) For example, the L and M photoreceptors may have a relatively large proportion of photoreceptors on the sidelines, while the S photoreceptors are pretty much all in the game. This isn't a random example, this is what happens when we see yellow.

[The previous paragraph was corrected from the original. Thanks, Max, for finding my whoops!]

When we shift the eye so that those photoreceptors are now seeing white, the S photoreceptors that were seeing yellow are very sensitive to the incoming blue photons, so there is a blue signal. This is true until the blue photoreceptors have reached equilibrium. The L and S photoreceptors who were seeing yellow have already adapted, so they are relatively less sensitive to photons in their part of the rainbow.

(Literally as I write this, I got an email telling me that an old buddy of mine just published a paper with some of his buddies entitled "The constancy of colored after-images". Naturally, I didn't actually read the whole thing, but the authors apparently argue that the brain has something to do with the afterimage effect.  

The complement of yellow could be blue or purple

The chromaticity chart can be used to predict the color (or at least the hue) of an afterimage color. We start by looking at yellow-- the start of the arrow on the diagram. When we look at white, represented by the black dot in the diagram, we have effectively added in some of "the opposite of yellow, so the hue we see is directly opposite of the hue of yellow. This diagram gives us an answer to the question of "what is the complement of yellow?" From the diagram, we can see that it's blue. Case closed. Blue is the unequivocal complement of yellow.

Chromaticity diagram, adapted from this site

But now it gets fun! Notice that the answer depends on where the white point is. The following chromaticity diagram shows that a cool white point (I show 55K, which is where my computer monitor is set) gives us a complement of yellow that is blue. The diagram also shows what happens if the white point is  warmer, as from an incandescent bulb. In this case, the complement of yellow is decidedly purple. I don't think this has ever been said before: The complement of yellow depends on the white point.

The complement of yellow can be either blue or purple

I have made a strong and possibly controversial statement. I put it in italics and copied it as the caption for the above image just to make sure everyone realizes just how important the statement is. But I have a little secret just between you, Dear Reader, and me. I'm not sure I fully believe what I said! 

Tuesday, May 2, 2017

Scatology and lug nuts

You know, I haven't done a long meandering, stream-of-consciousness kind of blog in a while. How about I start off by talking about poop? After all, everyone likes scatology. 

Scatology

There was a study published this past week in the ironically named journal Soft Matter entitled "Hydrodynamics of defecation". Now that caught my attention. And another thing that really cemented my attention was this quote from the abstract:

Despite the length of rectum ranging from 4 to 40 cm,
mammals from cats to elephants
defecate within a nearly constant duration of 12 ± 7 seconds (N=23). 

Wow. My first reaction was: "Well, none of them have cell phones or tablets!" The article went right down into the bowels of the physics that makes this happen. The findings are really quite unexpected. I mean, elephant dung is ejected at an astounding 0.075 MPH, but mouse dung is only going 0.0075 MPH. They explained the lack of variation on the stopwatch by saying that it was all about mucus. Larger animals have a longer transit system, but also have a lot more mucus to keep the trains moving.

I have 12 seconds to answer the age-old question

But my thoughts went more to "why"? As in, "why would Evolution design elephants to have more mucus?" Of course, that reminded me of another article about animals pooping that I read recently. A vet was asked about why dogs look at their owner when they poop. The explanation given by this vet is that animals are vulnerable when they assume the poopsition. They look to their pack mate (that is, you) in order to be alerted about danger.

So, my explanation is that animals are designed to fit the 12 second rule so as to avoid becoming some other animal's poop.

Pit stop

I started wondering... what else takes 12 seconds? My wife gave me a flippant answer about certain quick activities, but her answer was a bit embarrassing. So I went to Google to find a different answer. Here is an interesting factoid: animals and NASCAR drivers require a 12 second pit stop.

The pressure is intense when you're up against a bear in the woods!

Here is a quote from Greg Morin, who is the coach for a whole passel of pit crews:

Our goal is to hit a 12-second pit stop,
hit five lug nuts off, five lug nuts on (on each wheel) ...
get it full of fuel and ship it down pit road.

Left-handed lug nuts

Which brings me around to lug nuts. Here is a very interesting factoid about lug nuts. Back in the 1960's and into the early 1970's, the wheels on a car were held on with nuts with both left- and right-handed threads. Again, why did Evolution create such a silly design?

Keeping you regular since 1897

I found the answer in a well-written blog post on the MoparMax website entitled "The Mystery of Left-Hand Lug Nuts". The writer of this blog has the clever idea to use clever humor to engage histreader. Wow. I wish I'd thoughta that!

Anyway, here's the backstory. 

When a car is moving forward, the wheels on the right side (passenger side in the U.S.) will rotate clockwise. The wheels on the left side (driver side) will rotate counter-clockwise. When I first articulated that sentence my dog said "Huh? How can they be rotating in different directions?"

I went to the garage to look at my car and it hit me. Not the car, I mean the explanation hit me. The wheels rotate in the same direction, but your point of view changes. If I stand on the driver side and look at the front wheel, and then go on the other side and look at the other front wheel, I actually turn around 180°. Factoid: If you look at a clock from behind, it is running counter-clockwise. Words to live by.

When you accelerate a car, there is a torque applied to the lug nuts because of momentum; a clockwise torque on the passenger side, and a counter-clockwise torque on the driver side. If that torque actually makes the lug nut move with respect to the bolt, then it will tighten the passenger side lug nuts and loosen the driver side ones. Yikes! That don't sound so good.

In 1965, a non-profit firm by the name of the Motor Vehicle Research Center did the seminal study on lug nuts. (No pun intended.) (Well, maybe it was intended.) They hand-tightened some lug nuts and did a little test driving. They found that the lug nuts on the driver side were loosened during the test drive, and eventually fell off. Note that the nuts hand-tightened the nuts.

Whoops

Chrysler, Buick, Oldsmobile, and Pontiac all caught wind of the nutty story and bolted to make a design change. Reverse threaded driver side lug nuts became all the rage from 1955 to 1961.

But they don't do that no more. Why did they change? It's about a little thing called stiction. This is like friction, only it's a frictive force between two objects in contact that makes them resist moving until the force is big enough to overcome the stiction. If I have a book on a table, and I lift one side of the table, the book is initially not inclined to move. As I further incline the table, the book will eventually slide down and drop on my foot. I will say "ouch", which is an equal and opposite reaction, just as Newton would predict.

But the book initially not sliding runs counter to one of Newton's other laws, the "force equals mass times acceleration" law. The book should move a tiny bit when the table is slightly inclined. But stiction is a little thing that lives in the world of non-linear mechanics.

And speaking of mechanics, how do they make use of stiction? They tighten lugs nuts to 20 pounds of torque. That's enough to overcome the torque applied when we accelerate. If they promise to always give 20 pounds of torque, we can let them have all the lugs nuts threaded the same way.

Nuts who are left handed

One of my favorite words is sinistral, right up there with non-eucentric, defenestration, and funicular. Not surprisingly, one of my favorite sentences is "The sinistral man non-eucentrically defenestrated his friend from the funicular." More words to live by.

Sinister, sinistral -- Be careful to use the correct word

Sinstral has a dual meaning. First off, it means left-handed. But did you notice that the word sounds a lot like sinister? That's not a fluke. (Cuz a fluke is something that you don't want to have in your liver.) The two words have the same etymology. From the Online Etymology Dictionary entry on sinister we have this quote: 

Old French senestre, sinistre "contrary, false; unfavorable; to the left" (14c.)

Here we see the mixed meanings. There is an implication that left-handedness runs contrary to the normal order of things. And that left-handed people take too long in the bathroom.

The opposite of sinistral is dextral, or right-handed. Not surprisingly, the word dexterity comes from the same root as dextral. I mean, most people are more adept at tightening lug nuts with their right hand.

The sweet truth

Another word that shares a root with dextral is the word dextrose.

First let me say this. The end of the word (-ose) generally signifies sugar. The sugar in fruit is call ed fructose. The sugar in milk is called lactose. The sugar in malt is called maltose. And the sugar in french fries is called potat-ose. (Pause for groan...)

The Elmer's sauce really holds this gluecumber sandwich together -
an excellent source of glucose!

So dextrose is a sugar. What's with the prefix "dextro-"? It turns out that dextrose polarizes light to the right.

Dextrose, and other sugars really got a bad rap. My doctor tells me that sugar is associated with obesity, diabetes, and ants invading picnics. That's just silly. I have never witnessed an ant going into a diabetic coma at one of my picnics. I won't mention the behavior of any of my aunts at picnics.

High fructose corn syrup has gotten an especially bad rap. We find roughly 400 ounces of HFC in every 12 oz can of Coke. And it is really, really bad. Everyone knows that. It's all calories - no protein or fiber or nutrients. And it really messes with all that insulin stuff going on in our bodies.

(BS warning) But, don't believe any of that stuff. That's just fake science that is funded by the Aspartame Supplier Society. (BS warning) A lot of self-appointed health gurus are advocating that we should use "healthy sugars". While the sucrose that I shovel onto my Sugar Pops every morning may not be all that healthy, that sugar is highly refined. (BS warning) We know that anything that's refined has gotta be bad. The self-appointed health gurus tell us that unrefined sugars are actually good for us, since they contain nutrients. (BS warning) Thus, we should be drinking stuff with agave juice and baking stuff with honey. 

(Returning to my normal BS-free blog style) Honey, agave, turbinado, coconut palm sugar... these all have a minuscule amount of nutrients. But none of them are anywhere near being a health food. All of them are a zillion percent sugar, and too much sugar isn't good for you.

How about molasses?



There are a number of self-appointed health gurus who tout the benefit of molasses:

This is a link to a BS self-appointed guru site
Absolute claptrap on blackstrap
More advice for gullible people

Molasses had it's zenith as a health food with the book Look Younger; Live Longer, in which Gayelord Hauser promised us another five years of youthful life if we eat molasses. Here is a list of all the wonderful claims in the book, as recited in an FDA court case of 1951:

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The court case? It seems a health food store was shipped a package containing jars of Plantation brand molasses along with copies of Hauser's book. The book specifically endorsed Plantation molasses. The health food store displayed them together in their window, and used the book to help sell customers molasses. The court found that this constituted misbranding of the molasses. They held that bringing the book and the molasses together constituted labeling of the product, and that the claims were just plain stupid.

Interesting point though... Hauser didn't lose the case, the health food store was on trial. Freedom of speech allows Hauser to sell books with flat-out lies and preposterous health claims, but one cannot be so free when labeling products.

Don't get me wrong—blackstrap molasses does have significant amounts of calcium, iron, magnesium, and vitamin B6. But it has no fiber, no fat, and no protein. And it's 75% sugar. If you like the strong flavor, go ahead and indulge. But it's better to look toward yogurt, kale, broccoli, salmon, beans, whole grains, fruits, nuts, bananas, and poultry to get these nutrients.

Here is a YouTube video of some celebs of the time, poking fun at the whole "natural foods" movement:



Coming full circle

I should mention one of the audacious claims by one of the audacious websites pushing audacious health food remedies:

Blackstrap molasses has been
a sweet savior for more than a few sufferers of constipation,
be it chronic or occasional. 

I guess if you get enough molasses in your diet, you can get your pooping down to 12 seconds.

Tuesday, April 25, 2017

On the nature of emitted light, Part 3

I said in a previous blog post that I wanted to talk about fluorescent bulbs. I do. Really. And I will... in this very blog post. But before we get to that dessert, we need  to eat our peas and carrots. Let's talk about fluorescence.

The soon-to-be-famous sunburn analogy

I am of Northern European stock. I sunburn easily. Naturally, I wound up in a place where the Sun doesn't shine. Milwaukee. On those rare occasions when the Sun does shine, I absorb ultraviolet light. Later, my skin emits red light.

Lobster, anyone?

That's fluorescence.

Well, not really. I do absorb UV, and my skin does turn red. But that red is a reflective red, rather than a emissive red. My skin doesn't actually give off light. Factoid: sunburnt skin is red due to the increased concentration of hemoglobin at the surface. Hemoglobin absorbs bucketloads of light in the OYGBIV part of the spectrum, and reflects some at the R end. The reflected light is thus comprised chiefly of red light so skin looks red when we burn. (Interested in more about the color of human skin?)

Just in case you were wondering, my normally pasty-white Anglo-Swedish skin matches 2R04 in the Pantone Skintone guide.

If I recall correctly, though, I was talking about fluorescence. My explanation about sunburn shares a lot of the features of fluorescence. Light is absorbed at one wavelength, and is emitted at another wavelength. It is always emitted at a wavelength with less energy, which is to say, at the more relaxed higher wavelengths. For some molecules, the absorbed light is in the UV, and the emitted light could be at the red region of the spectrum. 

My understanding of the fizzicks involved

This will thankfully be a short section. I dunno nothin' about the fizzicks behind fluorescence. I mean, a molecule absorbs a photon, and that photon "kicks it up into a higher energy state". I have no clue what that means. I just know that I don't want to be around when my wife gets kicked up into a higher energy state.

Happy little benzine molecule

Later, the excited molecule gives up that energy, but not all at once. For some reason, it only gives it up a parcel at a time. Hence each fluorescent emission is at a lower energy (higher wavelength) than the excitation.

Note that I said molecule, and not atom. In the last post, kicking an atom up into a higher energy state was all about the orbits of electrons. Now it's about molecules. Surely that's a clue about what is happening when something fluorescences. But I am pretty ignorant when it comes to all that chemistry stuff. I'm the guy who once looked for a quantum mechanic to fix my compact car.

If I really understood any of this stuff, I would explain that
in this diagram from Kurt Nassau's book,
the wavy lines represent fluorescence

But in the spirit of pretending I know something...

There is a closely linked phenomenon called phosphoresence. Actually, it's the same phenomenon with a different name. Light is absorbed and is later emitted at a higher wavelength. The only difference is in how much later the emission happens. If it happens on a time scale where we don't notice (like nanoseconds or milliseconds), it's called fluorescence. If the delay happens on a time scale that we notice, for example if the fluorescent emission continues for seconds or hours after the excitation goes away, then we call it phosphorescence.

The distinction between fluorescence and phosphorescence is thus strictly anthropocentric. Just like the distinction between electromagnetic radiation and light (described in a previous blog post), the distinction is along a continuum and is not based on anything physical other than our meager, pitiful senses.

Examples of phosphorescence

Back in the olden days, engineers made a lot of use of phosphorescence. Cathode ray tubes (CRTs) in electron microscopes and in radar systems had long-persistence phosphors so that the image stayed latent on the tube long enough for us to notice. Quick show of hands... how many in the audience have used one of these devices?

A vintage scanning electron microscope (left) and a vintage radar tube (right)

Ok... let's try to open this up a bit. Show of hands again. How many in the audience have been to a historical museum (or my basement, same thing) and saw a TV that was two feett deep and weighed more than a pregnant and cross-eyed mule? That, my friend, was a cathode ray tube display, with a phosphor on the inside of the display end of the tube. Then again... maybe that was more accurately called a fluorescor, since we definitely didn't want it to persist for more than a 30th of a second.

(By the way, a scanning electron microscope is nearly identical in structure to the cathode ray tube in a television set. In fact, the cathode ray tube display was invented along side the scanning electron microscope. Someday I will blog on that topic.)

Certain lichens and mushrooms will glow in the dark long after the sun has gone down. Perhaps there is an evolutionary advantage to being seen as a part of the night life of the forest? I dunno. When it comes down to it, being a visible part of the night life has never given me much of an evolutionary advantage. It usually kicks my wife up into a higher energy state.

Some minerals fluoresce like an Anglo-Swedish color scientist with sunburn. Party-loving minerals like fluorite come to mind. I wonder where it got that cool name? Come to think of it, where did phosphorous get it's cool name?

Welcome back to the 60's

You can also see phosphorescence if you look at a fluorescent bulb in the dark, just after it has been turned off. Here we see the vague distinction between fluorescent and phosphorescent. Some of the stuff inside the tube is fluorescing, and some of it is phosphorescing. But more on that when I finally get around to discussing fluorescent bulbs.

But by far the most useful application is the little rubber duckie that was sitting on my wife's desk, at least until I absconded with it for a photo shoot. The rubber duckie is impreganted with some phosphor with excitation in the violet to blue part of the rainbow, and emission in the green to yellow part.

You can't claim to be uber-cool until you have one of thes on your desk

Examples of fluorescence

Certain versions of the Pantone guide had a few cards with the ever-popular 800 series inks. These inks all have fluorescent properties.

Picture of my 2005 Pantone guide

One of the more hip of these colors is Pantone 804, which is the orange ink. I almost called this dayglo orange, but that would be a misuse of the word, since Dayglo is a company. They make Dayglo pigments.

To demonstrate the phenomenal fluorescent properties of Pantone 804, I set up my spectrometer, my camera, and dug out my red, green, and blue laser pointers. (Note the repetitive use of the first-person pronoun my. It's all about me. Even when it's not, it's still about me.)

Here is what happens when I point the green laser pointer at Pantone 804. There is a strong peak in the green, at 546 nm. This is the reflection of the light from the laser pointer. But note the broader spectral stuff that appears from 560 nm to 700 nm. Lasers only put out a very narrow range of wavelengths. The broader peak must be fluorescence.


Now have a look at the spectrum emitted when the blue laser pointer is swapped in. The laser wavelength appears way far to the left, tucked away nicely at 390 nm. Then there's a broad peak that looks a lot like the broad peak in the previous spectrum. The excitation wavelength has changed, but the emission spectrum has not. 


Or at least the fluorescent emission spectrum hasn't changed a lot. Have a close look at the region from 460 to 510 nm. We see another bump. Not a big one, but a bump all the same. Why didn't this show up in the experiment with the green laser?

The explanation can be found above. I don't mean in the Heavens, but earlier in this blog post. I wisely said: "each fluorescent emission is at a lower energy than the excitation." The green laser just didn't have the gumption to excite emission in the blue part of the spectrum.

This should help us explain the frankly quite boring results with the red laser pointer that are shown below. We see a red peak, which is way up at 688 nm. Ho-hum. Any fluorescence would have to be above that, so we get bupkis in the way of fluorescence.


Fluorescent whitening agents

How about another example? I have previously touched on the topic of additives that make paper whiter. I mentioned it in a blog about color-related standards in the print industry. I also blogged about how different spectros deal with the problems caused by the whitening stuff. And I blogged about a conference with a sub-conference on the little buggers.

The image below shows the reflectance spectrum of one paper stock. You might notice something a bit peculiar about it, especially around 430 nm. Go ahead. Have a look. And take note of the scale on the left-hand side. The observant reader will have noticed that over 120% of the light that hits the surface is reflected back. For the mathophobes in the crowd, 120% is more than 100%. So... this paper is creating light?

Note the attractive little bump at the blue end of the spectrum

So, here's the scam. Paper normally looks like a brown paper bag. You can make it whiter by various means, including bleaching it, but that's expensive. Not horribly expensive, but there is cost involved. And people like their paper to be white. In fact, studies have shown that people prefer paper that is just a tad on the blue side of true white.

A cheaper way to get white (and the only way to get blue) is to add fluorescent whitening agents to the paper. There is a family of compounds known under the name of stilbenes. Below is the excitation / emission spectra of stilbene stolen from a TAGA paper by Dr. David Wyble and some Anglo-Swedish guy who likes to think of himself as a color scientist. The blue line shows the amount of energy that the stilbene absorbs, as a function of wavelength. Note that this is in the UV region, mostly all between 300 nm and 400 nm. The red line is the wavelengths where that energy is fluorescently emitted. Pretty much what we would call the blue region of the spectrum, from 400 nm to 500 nm. 

Yest'day I's fluorescin', and today, I still-been fluorescin'

Adding stilbene to a paper stock will boost the blue. Since drab, dull, yellowish paper is blue-deficient, this will make it look whiter. Well, provided there is some UV light to get it excited. Paper is not creating light, it's redistributing the energy from the UV to higher wavelengths.

The image below illustrates that. There are three sheets of paper here. I wrote on them, annotating the amount of FWAs. On the right side, I took a picture of the three sheets under regular old garden-variety light. The three look similar. On the left we have a picture of those same three sheets under a UV flashlight. OMG! It is pretty obvious that there is some sorta difference going on! 

Three sheets to the fluorescent wind

BTW, FWA AKA OBA. Someone got the bright idea to call these brighteners OBAs. This stands for Optical Brightening Agents. I agree, the term fits. Stilbene brightens paper optically. But so does bleach, calcium carbonate, and titanium dioxide, and a good coat of white paint. These four will all increase the reflectance of paper in the blue region. But only stilbene does it with a fluorescent flair. So, if you hear someone call stilbene an OBA, wag your finger at them and tell 'em John the Math Guy says that they are using the term improperly.

Remember back when I took note of the little bump in the spectrum when I used the blue laser pointer? You may have guessed by now. It was stilbene. The paper that the Pantone book is printed on has quite a bit of FWAs. It's kinda hard to find paper today that doesn't.


Well. Look at the time! It's about time to wrap up this blog post on the nature of emitted light. Today I taught you everything I know (and a little bit more) about things that fluoresce in the night. There was something else I wanted to say about fluorescent light... Can't remember what it was. I guess it can wait until the next blog post. That one will be about fluorescent bulbs. I promise.