Category Archives: Basic Science

Demise of Dinosaurs

by James R. Barrante, Ph.D.

It is well-known that dinosaurs disappeared from the planet over a relatively short period time (on a geological time scale).  Many theories have been floated as to what caused their rapid demise.  The latest is that an asteroid struck the planet about 60 million years ago and did them in.  But there is another possible and perhaps more plausible explanation.  It is pretty clear that large animals like dinosaurs required a tremendous amount of food.  Atmospheric levels of CO2 during the era of the dinosaurs is estimated to be around 3000 to 4000 ppmv, ten times what it is today.  It is very unlikely that dinosaurs could have survived at CO2 levels of 400 ppmv or less, a fact that seemed to be overlooked in recent movies describing the Jurassic period.

If one looks over the history of atmospheric CO2 (you can find papers online), you will find that during a period from about 100 million years ago to about 60 million years ago, the period estimated to be when dinosaurs went extinct, atmospheric CO2 levels fell from about 3000 ppmv to 250 ppmv.  If that is, in fact, the case, an asteroid hit would not have been necessary to get rid of all these large animals on the planet.  We know from experience that pre-industrial levels of 280 ppmv CO2 caused mass famine to Earth’s populations in the 1700’s and 1800’s, when these populations began to grow.  It is highly probable that dinosaurs simply starved to extinction, the large vegetarians going first, then large meat-eaters, and finally smaller species.  Moreover, along with this, a reasonable explanation for the cause of this large drop in CO2 level would have been a “rapid”  (remember, on a geological time scale a million years would be “rapid”)  drop in ocean temperature, causing the excess CO2 to dissolve in the oceans.  We see the reverse happening today.  The temperature of the oceans is increasing and atmospheric CO2 levels are also increasing accordingly, lagging behind by about 400 years.

In any case, a rapid cooling globe would have made it difficult for large, cold-blooded animals to survive, thus insuring the repopulation of the globe by small, furry, warm-blooded mammals.  This scenario most likely will occur again.  Experts predict that in order for humans to make it through the 21st century, food supplies will have to double.  There is no way this is going to happen at atmospheric levels of 400 ppmv.  For large animals to survive through the 21st century, atmospheric CO2 levels would have to increase to 700 or 800 ppmv.  Will governments allow that to happen?  Not if the rank and file continue to believe that our source of food on the planet is changing the climate and this is going to be devastating.  Actually, what will be devastating will be the attempts by misguided (I am being kind) individuals to lower atmospheric levels of CO2 , which will destroy food supplies for most large animals, including humans, on the planet.  Insects probably will survive.  To quote the newspaper comic strip character Pogo, “I have seen the enemy and it is us!”

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Filed under Basic Science, Carbon Dioxide Properties, Solubility of CO2 in Water

Physical Chemistry for the Biological Sciences

Poster

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September 11, 2014 · 12:19 pm

The Taste of Carbon Dioxide

by James R. Barrante, Ph.D.

A few years back, the Environmental Protection Agency deemed that the gas carbon dioxide is a pollutant.  The dictionary defines a pollutant as a substance that contaminates or poisons.  It would be useful to look at how carbon dioxide stands up to this definition.

The composition of Earth’s early atmosphere was approximately 95% carbon dioxide and water vapor, very similar to the atmosphere of Venus today.  It contained no oxygen.  Any oxygen that might have formed, reacted chemically with metals in the hot crust (e.g., iron, copper, calcium, magnesium, aluminum) and metalloids (silicon) to form oxides.  As the planet cooled to below 100˚C, something that Venus was never able to do because of its nearness to the sun, the water vapor began to condense forming lakes and rivers, and because of its high solubility in liquid water, the atmospheric carbon dioxide began to dissolve in the Earth’s waters.  When carbon dioxide dissolves in water, it forms a weak acid, known as carbonic acid, that will react with any alkaline (basic) substances to form bicarbonates and carbonates.  Earth’s waters began to attack the alkaline oxide minerals, like calcium oxide, to form carbonates, and since most carbonates are not soluble in water, they settled out of lakes and oceans to form rock such as limestone and marble.  This left more room for more carbon dioxide to dissolve.  The level of atmospheric CO2 began to drop.  Moreover, certain chemical reactions in the atmosphere began to produce nitrogen gas, a relatively inert gas that reacts slowly with other elements.  The composition of the atmosphere began to drastically change.

The appearance of living organisms on the planet further changed the chemistry of the planet.  While the chemical reaction

CO2     +     H2O       →     sugars     +       O2   

is not energetically possible, certain plants learned to make a photosensitizer, known as chlorophyll, that allowed them to use the sun’s energy to force this reaction to occur.  Because chlorophyll absorbs in the red region of the spectrum, plants appeared to be green.  The formation of large quantities of green algae further reduced the level of atmospheric carbon dioxide, producing an atmospheric waste poison, oxygen gas.  Luckily, the level of oxygen gas in the atmosphere would remain low.  This is because any newly formed oxygen gas would quickly react with metals in the Earth’s crust to form the metal ores that are present today.  Likewise, the reaction of vast amounts of silicon, the second most abundant element with oxygen, formed silicates and large regions of sand.

Animals began to evolve in the waters, feeding on the green plants (and on each other), but were confined to the waters, because of the deadly ultraviolet radiation reaching the surface of the Earth from the sun.  One good effect, however, did result from the oxygen in the air.  Lightening storms supplied large amounts of energy that allowed another type of oxygen, O3, and known as ozone, to form and this gas began to build up in the upper atmosphere.  Ozone has the ability to filter the ultraviolet radiation from sunlight, and this eventually allowed animals to move from the oceans onto the land.  We must keep in mind, however, that the food chain remained in tact.  Carbon based plants obtain their carbon atoms solely from atmospheric carbon dioxide.  Animals get their carbon atoms by eating the plants or eating the animals that eat the plants.  At levels of atmospheric CO2 in the thousands of parts per million range, lush plant life covered the Earth’s surface, allowing animals that fed on these plants or fed on the animals that ate these plants to grow very large. This could never happen today.  At levels of 100 ppm (parts per million) CO2 plants begin to die.  At levels of 200 ppm plants struggle to survive.  At levels of 300 ppm (pre-industrial CO2 levels) there was barely enough food for pre-industrial populations to survive, at todays levels of 400 ppm, it is not likely that there will be enough food on the planet to feed the expected large increases in population in the 21st century.

We know that atmospheric CO2 levels are controlled by the temperature of the oceans. If we are lucky, oceans will not cool and cause carbon dioxide levels to plummet. It appears that declaring our source of all the food on this planet a pollutant was not a stroke of genius. It was a stroke of ignorant stupidity.

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Filed under Basic Science, Carbon Dioxide Properties

The Whole Truth

by James R. Barrante, Ph.D.

We have all seen the famous ice-core graphs from data taken from Vostok Station, Antarctica.  The CO2 graph going back some 400,000 years is particularly interesting.  The graph clearly shows atmospheric levels of CO2 rising and falling on a periodic basis.  The maxima, occurring approximately every 100,000 years at a level of about 280 ppm, represents the four interglacial periods, like the period we have been in for the last 10,000 years.  By contrast, there are four minima at approximately 180 ppm corresponding to the periodic ice ages experienced by the globe over the past 400,000 years.  We must keep in mind that on a scale of 400,000 years, a 200-year time period is about the width of the ink line.  Usually attached to the end of of the graph, representing a time period of about the last 150 years, is a vertical line shooting up to over 350 ppm, and then extrapolated into the future.  The caption found on many of these graphs is, “for the past 400,000 years CO2 levels in the atmosphere have never exceeded 280 ppm until now.”  It is perhaps one of the most dishonest interpretations of data I have seen in my long scientific career.

Now, before going on, let me say that there is nothing dishonest about the ice-core data itself.  It represents a beautiful piece of research done under miserably cold conditions by a group of scientists with the best intentions in mind.  What is dishonest is the idea that the graphs represent global temperature and global CO2 levels.  For example, ice core data came from samples of ice taken from the deep in the snowpack of Antarctica.  The ice came from snow that fell through the atmosphere of Antarctica (not New Jersey) and CO2 levels were determined from air trapped in those bubbles.  It is unlikely that those bubbles of air represent anything but the air over Antarctica.

The last part of the graph showing the last 150 years where “global CO2” shoots up to over 350 ppm was not constructed from Vostok ice-core data.  It was constructed from data obtained from measurements taken on Mauna Loa, an active volcano.  It would seem logical that the water temperature around Hawaii is a little warmer than the waters surrounding Antarctica, and since we know that atmospheric CO2 levels are controlled by water temperature, it would make sense that (volcanic action aside) CO2 levels around the Hawaiian Islands should be higher than around the South Pole.

So, when we say that CO2 levels never have exceeded 280 ppm for the last 400,000 years, that has only been verified over Antarctica.  We have no research suggesting that this is true for any other part of the globe.  You see, in science, an average of a specific property such as temperature, taken at different points with different measuring devices is just a number with no specific meaning.  The number describes something that does not exist.  For example, if you did not know the shape of an NFL football and I told you it had an average diameter of 6.64 inches, what shape would you expect it to have?  A sphere?  Obviously, the average diameter of a football doesn’t exist.  The same thing is true for average global temperature, average CO2 level, average sea level, or average global anything.  To suggest that it does is scientifically dishonest.

The only time that a an average is scientifically significant because it increases the precision of a measurement is when one measures the exact same thing with the exact same measuring device, under the exact same conditions hundreds of times.

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Filed under Basic Science, Global Warming

Can Infrared Light Pass Through Glass?

by James R. Barrante, Ph.D.

There seems to be some controversy, particularly by laypersons, as to whether infrared light can pass through glass.  The correct answer is, “That depends!”  Infrared radiation spans a wide region of wavelengths.  At the shorter wavelength end, near visible red, the behavior of infrared light is not that different from visible light, except, of course, humans cannot see it. This radiation, called near infrared, does pass through glass. A better way to look at it is to say that it is not absorbed by the glass. It’s energy is too large to excite atoms in molecules to higher vibrational states. If you own an electric stove, you will experience this light just before the coils begin to glow a dull red. If you doubt that it is there, put your hand near a coil. Your skin actually “sees” this light.

The middle band of wavelengths, generally referred to as thermal infrared, is infrared light produced by matter around room temperature.  It is this band of infrared that cause atoms in molecules to jiggle, and jiggling atoms generate heat.  This radiation is strongly absorbed by matter, and will not pass through glass.  It is also the radiation absorbed by CO2.  So any demonstration that attempts to show that a glass jar filled with CO2 will heat up faster and to a higher temperature than a jar filled with air by shining infrared on both jars has been staged. Oh, the gases in both jars will heat up. If you heat up any container, glass or otherwise, any gas inside the container also will heat up.

At the other end of the infrared spectrum, the far infrared, the light is significantly lower in energy, approaching that of microwaves and radio waves.  This type of radiation generally is produced by colder substances.  It is a more controllable heating radiation and is the type used in infrared heaters and saunas.

As a final reminder, infrared radiation is a form of light, not heat.  Heat is transferred by molecular collisions and is relatively slow.  Infrared radiation moves at the speed of light and is fast.  We associate infrared light with heat only when it interacts with matter and excites vibrational modes of motion of atoms in molecules.  In order for that to happen, a vibrational mode must set up an oscillating electric field in the molecule that can couple with the electric field component of the infrared wave.  While the nitrogen atoms in N2 vibrate, they are unable to create an oscillating electric field.  Consequently, N2 is not infrared active.  Carbon monoxide, CO, is a polar molecule and therefore will set up an oscillating electric field when the carbon-oxygen bond stretches.  It is infrared active.

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Filed under Basic Physical Chemistry, Basic Science