See the Tabbed Pages for links to video tutorials, and a linked list of post titles grouped by topic.

This blog is expressly directed to readers who do not have strong training or backgrounds in science, with the intent of helping them grasp the underpinnings of this important issue. I'm going to present an ongoing series of posts that will develop various aspects of the science of global warming, its causes and possible methods for minimizing its advance and overcoming at least partially its detrimental effects.

Each post will begin with a capsule summary. It will then proceed with captioned sections to amplify and justify the statements and conclusions of the summary. I'll present images and tables where helpful to develop a point, since "a picture is worth a thousand words".

Saturday, July 15, 2017

Scientific Underpinnings of Modern Medicine - Vaccination

Summary. Our understanding of the human immune system made tremendous progress all through the 20th century, continuing even to the present day.  As part of this effort, important advances have been made in vaccine development, saving millions of lives worldwide.  But false reports linking vaccination with autism have led to rejection of vaccination by many parents, who fear incorrectly that vaccination may trigger the later appearance of autism.
Science can only proceed by open-ended inquiry, untainted by preconceived biases.  Unscientific proposals that are counter to the results of objective inquiry, such as the harmful movement to shun vaccination, are unproductive.  They harm society at large by diverting attention and wasting resources.  Human progress relies on critical verification of scientific discovery, and on building further on the progress made.

 
Allison had married relatively late, and was happy to have her infant son and husband as her family setting. 
As a parent, she’s been aware of the controversy in the popular press surrounding the question of a possible link between administering vaccines to infants and the later development of autism.  Having done considerable research on the controversy during her pregnancy, Allison realized she needn’t have concerns about this. She concluded that a possible connection with autism was mistaken. She proceeded to give all the vaccines recommended for growing children to her son, who continued growing to become a healthy child. 

                     +                   +                   +                   +                     +

The modern practice of medicine has benefited enormously from the results of scientific research in the biological and medical sciences.  We all are better off from the results of these efforts.  The previous post dealt with the discovery of the structure of DNA and the genetic code, and the immune system.  Here I discuss the immune system in vaccination, and fallacies surrounding use of vaccination. 
Antibodies.  One of the ways that the immune system reacts to, and fights against, a foreign (likely disease-causing) particle, such as a virus, cell, or parasite, is to generate antibodies (a group of special protein molecules) that specifically react against particular structures on the particle (the antigen).   The antibodies bind molecule-to-molecule to the antigen, inactivating the particle (see the previous post) and preventing the disease or minimizing its harmful effects. 

Vaccines.  Vaccination is another process involving the immune system.  It has long been used as a way of deliberately confronting the immune system of a healthy person with a component obtained from, or that is similar to, a foreign antigen that causes disease in humans, in order to generate protective immunity against appearance of the disease later on.  The process was originally developed by Edward Jenner in the 18th century for preventing smallpox.  It was known anecdotally that milkmaids who contracted cowpox from infected cows rarely became infected with smallpox.  Cowpox causes a similar, but weaker, illness in humans than smallpox. 
Jenner’s scientific breakthrough was to take the fluid produced in the cowpox infection, and to introduce it under the skin of healthy people.  He found that the treated people did not develop smallpox.  (We now understand that his procedure induced the immune system to produce antibodies that specifically attack the cowpox- or smallpox-causing substance, a virus.  A protein on the cowpox virus is sufficiently like the corresponding protein on the smallpox virus that the human antibodies that bind to cowpox also bind to smallpox, thus inactivating it.)

Many vaccines have been developed since then to immunize people against infection from viruses or bacteria.  Today commercial vaccines contain a very small amount of a preservative to keep them sterile.  Most vaccination is for young infants and toddlers, to protect against diseases such as diphtheria, whooping cough and measles.
Vaccines and Autism.  Public fear over use of vaccines has developed over the past two decades. It started with an erroneous and misleading report of a connection between vaccination and autism in children.  (See Science (2017), Vol.356, pp.364-373.)
In 1998 a physician, Andrew Wakefield, published a report in a respected British medical journal suggesting that use of the measles-mumps-rubella triple vaccine could lead to later development of autism.  His report led to a 20% reduction in vaccinations in Britain.  But in 2004 a journalist found that Wakefield was involved in trying to patent a competing measles vaccine, which was a serious conflict of interest.  The journal, in further investigations of its own found serious ethics violations by Wakefield and retracted his original paper in 2010.  A short time later the British General Medical Council revoked his license to practice medicine at all.  Thus Wakefield’s original findings were definitively determined to be invalid.
There is also a more general suspicion by many parents of an unwelcome intrusion by government authorities into a family’s health care decisions, as well as other nonscientific fears.
More recently, the Journal of the American Medical Association reported no difference in rates of autism between vaccinated and unvaccinated children. (See Science, cited above.)

Thimerosal, a mercury-based preservative, had been used in very small amounts in vaccines until 2001, when its use was discontinued in almost all vaccine compositions.  Even so, four years later in 2005 the lawyer Robert F. Kennedy Jr. (late President John F. Kennedy’s nephew) alleged in Rolling Stone and Salon that the U. S. government was hiding evidence that use of thimerosal led to increased incidence of autism.  The data Kennedy cited were mistaken, and in 2011 Salon retracted his article. 
Both the U. S. Centers for Disease Control and Prevention and the United Nations’ World Health Organization have concluded that thimerosal causes no health problems in children. (See Science, cited above.)  By contrast, a report published online in Nature on July 12, 2017 compares social interactions of infants and toddlers among pairs of identical twins, pairs of fraternal twins, and paired but unrelated single-birth infants and toddlers.  A genetic component was detected among children in the study that later were diagnosed with autism but that was absent in normal children.  This work shows that our scientific understanding of autism is growing as rigorous investigation proceeds.

Public refusal of vaccination places the children of rejecting parents in considerable danger because the infections that the vaccines inhibit cause serious or fatal diseases.  If enough children remain unvaccinated contagion can spread the diseases among them.  On the other hand, the World Health Organization estimates that 2 to 3 million lives a year are saved because of successful vaccination programs.

Conclusion 

Remarkable advances in biological and medical science, including immunology, have been made since the end of World War II.  Among these is cancer immunotherapy, in which antibodies are created to antigens on cancer cells, as if the cancers were foreign invaders like viruses and bacteria (see the previous post). 
Immunological research has also led to use of new, effective vaccines, raising immunity to dangerous diseases in our bodies.  To our detriment, nonscientific, indeed antiscientific, campaigns against the use of vaccines in children have increased the number of susceptible children among the populations of many developed countries, including the U.S., potentially to dangerous levels.  The spread of virulent infections is enabled by the failure to vaccinate. (See Science, cited above.)

Scientific investigation seeks to expand our knowledge and understanding of the world we live in.  Reflecting on the state of knowledge at any time, a curious scientist poses a question or suggests a hypothesis.  Experiments directed toward answering the question or verifying the hypothesis are carried out as an objective pursuit, further characterizing the natural world, without introducing preconceived biases.  Conclusions are then drawn based on the new results obtained. These frequently lead to practical applications that improve our health and prolong lives. 
The intrinsic value of scientific study should be defended and supported by all to continue its progress, and to promote human welfare.

© 2017 Henry Auer

Wednesday, July 12, 2017

Scientific Underpinnings of Modern Medicine – DNA, Cancer and Immunotherapy

Summary. Biological science has made tremendous progress since James Watson and Francis Crick presented their model for the structure of deoxyribonucleic acid, DNA.  Their model built on, and provided explanation for, important findings about DNA that were already known. 

Since then, important progress has been made, for example, in analyzing the base sequences, i.e., the chemical code, of specific genes and using that information for diagnostic and therapeutic purposes. Gene sequences that identify mutations in breast cancer genes alert physicians to the possibility that virulent malignancies may develop later in life.  Another genetic aberration, in the HER2 protein, permits targeting it with a therapeutic antibody, a major step forward.

Science can only proceed by open-ended inquiry, untainted by preconceived biases.  Unscientific proposals that oppose the results of objective inquiry are unproductive.  They harm society at large by diverting attention and wasting resources.  Human progress relies on critical verification of scientific discovery, and on building further on the progress made.


Allison just left her gynecologist’s office, with a referral to have a breast biopsy.  She was apprehensive, of course, since she had married relatively late, and was worried about her infant son and husband. 

Allison had been particularly concerned about her biopsy, because she’s a relatively late-age mother.  While breast cancer can arise in women of all ages, she had only recently had her first child, a son. 

A couple of weeks later Allison went in for the biopsy procedure.  In addition to the well-established examination of the samples from the specimen under a microscope, a small portion was also sent for DNA analysis, which searches for a genetic match for a mutation associated with some breast cancer cases.  When such a match is found, the patient is more likely to develop breast cancer during her lifetime. The pathologist found no visual evidence for cancer in Allison’s samples, and the mutant DNA also was not present. 

Now, with the negative biopsy result, and the information from the genetic analysis, Allison can continue to enjoy watching her son develop.  But she will be under close medical scrutiny for the possibility that a cancer may develop later, as the years pass.

                     +                   +                   +                   +                     +

The modern practice of medicine has benefited enormously from the results of scientific research in the biological and medical sciences.  Here I describe the discovery of the structure of DNA and the genetic code, and the immune system.  The next post discusses the immunology of vaccination and the unproven fears that vaccines may be connected to autism.

DNA and the Genetic Code.  Modern understanding of genetics has progressed dramatically since 1953, when the double helical molecular structure of DNA, the material containing the genetic code of all cells, was worked out by James Watson and Francis Crick (based on additional contributions from Rosalind Franklin). Other renowned scientists of the time had tried but failed to predict the structure.  Watson and Crick discovered that the structure can only be correctly constructed if, considering the four DNA building blocks, an adenine on one strand of the helix is paired with thymine on the opposing strand; and guanine is paired with cytosine (see the graphic below). 
 

Diagram showing the double helix structure of the DNA molecule.  Guanine (green) on one strand can only bind with cytosine (red) on the other, and thymine (orange) only with adenine (blue).

 
The sequence of the four building blocks, generally called nitrogenous bases, along the DNA strand, defines a code that specifies how each protein is synthesized in the cell. Proteins are the large molecules that variously define a) how cells go about their molecular business, b) provide structural elements that give cells their sizes and shapes, or c) communicate with neighboring and distant cells of the organism.

Breast Cancer Susceptibility.  As time passed, the base sequences of many single genes in cells have been worked out.  Among them were the two breast cancer, or BRCA, genes, BRCA1 and BRCA2.  A mutant, or variant, form of either of the BRCA genes can be easily identified by a genetic analysis that seeks the occurrence of the mutant base sequence in a subject’s DNA.  Having the mutant form increases the risk for later development of breast cancer by about 50%. 

Antibody therapy.  Certain breast cancers can be treated with some new drugs that are the result of major recent advances.  A breast cancer biopsy specimen can be assessed for the presence of a larger than normal level of a surface protein, the human epidermal growth factor receptor 2 (HER2) protein, which makes the cancer highly malignant.  Such breast cancers can be treated with a new biotechnology product, a monoclonal antibody drug called Herceptin®, that binds to and inactivates HER2.

Polyclonal antibodies.  One of the ways that the immune system reacts to, and fights against, a foreign (likely disease-causing) particle, such as a virus, cell, or parasite, is to generate antibodies (a group of special protein molecules) that specifically react against particular structures on the particle (the antigen).   The antibodies bind molecule-to-molecule to the antigen, inactivating the particle. 

Our natural immune system works by creating many antibody proteins that differ at the molecular level one from another, but that all bind to the foreign particle.  Each antibody protein arises from a distinct, specific cell in the immune system.  Because the natural immune reaction generates this large number of antibody species, collectively they are called polyclonal antibodies (see the image below). 


Left: Polyclonal antibody molecules (dark gray) in a sample bind different portions (colored pairs) of an antigen.  Right:  After selection of one of the antibody species, the antibody sample contains only one kind of antibody molecule, a monoclonal antibody, that binds only one portion of the antigen (blue pairs).
Source: http://absoluteantibody.com/antibody-resources/antibody-overview/antibodies-as-tools/


Monoclonal antibodies. Immunological research revealed that different antibody molecules in the polyclonal set bind differently to the antigen (see the image above).  Some that bind weakly only partly inactivate the antigen, whereas others that bind quite tightly are efficient as inactivators.

In 1975, Georges Köhler and César Milstein (Nature, 1975 Aug 7;256(5517):495-7), developed a technique that separated immune cells from one another, as well as creating hybrid cell fusions that never died. They cultured each isolated immune cell in a growth medium so that each culture now contained the daughter cells originating from a single fusion cell.  Now the antibody molecules in each culture were all identical to one another.  These are called monoclonal antibodies (see the image above).  The resulting monoclonal antibodies could be tested for how well they neutralized the antigen.

Herceptin® is the trade name for a monoclonal antibody drug that reacts specifically with the HER2 protein on a tumor cell surface, preventing the normal functioning of the receptor and inhibiting tumor growth.  In essence Herceptin® treats HER2, a normal constituent of human cells, as a foreign substance, attacking and inactivating it.

Conclusion 

Remarkable advances in biological and medical science have been made since the discovery of the DNA double helix and the identification of the genetic code.  Since about 2000 we have the sequences of all the genes in human DNA.  This permits identification of normal and pathological conditions in humans.  Understanding of the origins of many cancers has resulted, and has led to new therapies.  Among these is cancer immunotherapy, in which antibodies are created to antigens on cancer cells, as if the cancers were foreign invaders like viruses and bacteria. 

Science advances by the objective pursuit of new information about the natural world.  The results frequently lead to practical applications that improve our health and prolong lives.  The intrinsic value of scientific study should be defended and supported by all to continue its progress.
© 2017 Henry Auer

Wednesday, June 14, 2017

Our Life in a Technology-Driven World

Summary. Our lives in the early 21st century benefit from remarkable changes wrought by science and technology in the last 200 years.  As a human endeavor, science consists of a method of inquiry into the natural world based on open-minded investigation, rather than one biased in one direction or another that develops support for a desired point of view.

Certain science-based phenomena have come to light in recent decades that adversely affect human health or damage the environment.  Rigorous study showed that, in each case, products or practices of large corporations turned out to be responsible.  Those commercial interests sought to raise questions about the scientific results in the minds of the public, rather than continue further research to develop sound solutions to the problems.
We humans have benefited from the advances provided by science and technology.  We cannot justifiably select the science we like and dismiss the science that we don’t.

 
Benedict (Benny to his friends) is waking slowly, after having stayed late at a party last night.  He’s already enveloped in the soothing sounds of his favorite music, Sounds from Space, that invariably puts him in a mellow mood.  His radio came on with the music using an alarm setting.   He also plays music on his CD player; over the years he’s accumulated an extensive library of CDs.  His tastes run quite eclectic.
At last Benny swings himself out of bed and hops on to his Stair Stepper for a workout.  It’s equipped with a TV monitor so he can watch the latest news as he exercises.
After a leisurely breakfast, he gets ready to head out for his weekly frisbee match.
After the vigorous physical exertion of the game, he comes home and turns on his air conditioner to make his apartment more comfortable.  Air conditioners are effective because they lower the air temperature, but equally importantly, they remove some humidity from the air.  Lower humidity makes the body feel cooler because its perspiration evaporates more easily, cooling the skin.
Later, that afternoon, Benny has decided to attend a lecture at the local library on the shoreline habitats for all manner of wildlife. Lately he’s become even more interested in the natural world, and how different species interact in their habitats.  The lecturer is using a computer-driven digital projector, and he emphasizes his discussion as he goes along using a laser pointer.
In the evening, Benny and Valerie, his girlfriend, went out for dinner and came back to relax with a movie streamed over the internet.

                     *                    *                    *                    *                     *

Benny’s day, a rather routine one in today’s world, benefited from many products that rely on developments in science and technology.  Here we’ll discuss two classes of appliance, and a third that because of careful scientific investigation, became quite controversial.
Telegraph, and radio and television.  For all of history before the industrial revolution, news, books and artwork traveled only as fast as humans could carry them.  Walking and travel by horseback could transmit physical objects, whereas drumbeats, smoke signals and semaphore signaling could communicate more terse messages. 
In the 1830’s and 1840’s clusters of inventors in the U.S. and England separately developed the telegraph.  In the U. S., one of those was Samuel Morse.  The previous post mentioned that nineteenth century physicists developed an understanding of the reciprocal interactions between electricity and magnetism.  With the telegraph, a key pressed by a sender completed an electric circuit so that current could instantaneously flow as far as a conducting wire could be strung.  At the destination, the current activated an electromagnet to sound a click.  In addition to developing the technology Morse invented Morse code, by which the spacing between clicks permitted coding every letter of the alphabet.  The technology developed into the Western Union Company (cofounded by Ezra Cornell, for whom the university is named) which strung wires across the U. S.  This revolutionary technology liberated the transmission of information from the historical limits of personal or visual/auditory messaging.
The telephone built on the electromagnetic transmission of coded messages to the direct, immediate transmission of sound, especially the human voice.
The laws of physics relating to electromagnetism also led to radio and television transmission.  Perhaps, if you live in an older home, you’ve noticed that a window sash will buzz or vibrate in its track as an airplane or a truck passes by.  The window sash has its own characteristic vibration.  The sound from the passing plane or truck can set the window vibrating, but only if the vibrations of the sound waves have the same pitch as the natural vibration of the window sash.  This is variously called forced vibration or sympathetic vibration. 
Radio and TV transmission and reception work the same way.  A radio transmitter is designed to emit radio waves at a specific vibration frequency.  If a specific receiver circuit in a radio or TV is adjusted to vibrate at the same frequency, the broadcast signal is picked up by the receiver, amplified, and delivers sound and picture images.  If the tuner is not adjusted to the appropriate frequency it will not receive the broadcast signal.
Benny’s air conditioner is filled with a refrigerant gas, a chlorofluorocarbon.  The technological principles underlying operation of refrigerators and air conditioners were explained in the preceding post. 
Use of chlorofluorocarbons (CFCs) is an example where a useful technology turns out to have harmful consequences.  When they were developed and entered the market, the use of CFCs as refrigerants and in other applications became widespread. During the 1980’s, however, researchers discovered that the amount of ozone in the stratosphere (a zone centered around 15 mi. above Earth’s surface) was diminishing compared to earlier years. Stratospheric ozone is beneficial because it filters out ultraviolet light from incident sunlight.  (This should not be confused with ground level ozone, a health hazard, which is produced by smog on hot days.) If ozone becomes depleted, more ultraviolet (UV) light can reach the surface of the earth.  The additional UV could increase the incidence of skin cancer the world over if the ozone depletion were to continue.
After some years atmospheric scientists showed clearly that chlorofluorocarbons (CFCs) caused the ozone depletion.  These compounds enter the atmosphere when refrigeration equipment leaks its refrigerant or is improperly disposed of; when we use spray cans, such as hair spray; and when CFCs are used as industrial foaming agents.  Even a small amount of CFCs has a powerful destructive effect because the active component derived from CFCs is re-used in the chemistry of ozone destruction many times over.    For this discovery, Paul Crutzen, Mario Molina, and Frank Rowland were awarded the Nobel Prize in 1995. 
In light of this new understanding almost 50 of the world’s nations, the main producers and users of CFCs, agreed to the Montreal Protocol of 1987 to phase out use of these compounds.
Corporate Interests generated doubt and delay.  Early on the manufacture of CFCs, and of the spray cans that use them, became a lucrative business.  Rigorous scientific  research, pursued as a quest for understanding of basic properties of the natural world, led to evidence showing that CFCs were responsible for destroying stratospheric ozone.  As this evidence was accumulating, however, the companies  sought to neutralize the impact of the scientific results (Wikipedia; N. Oreskes and E. M. Conway, “Merchants of Doubt”, 2010, Bloomsbury Press, New York), without offering scientific evidence to support their position. 
In one paper, prepared by Greenpeace for the 9th meeting of participants in the Montreal Protocol in 1997, a threefold corporate strategy of disinformation used by a major corporation was summarized:
Deny that CFCs are responsible.  The corporation wrote in 1979: "No ozone depletion has ever been detected...all ozone depletion figures to date are based on a series of uncertain projections." 
Delay.  In the years surrounding the signing of the Montreal Protocol, this corporation sought to delay implementation of its terms by lobbying activities.  In 1986 it testified before Congress: "we believe that there is no immediate crisis that demands unilateral regulation."
Dominate.  The industry had already developed alternatives to CFCs, closely related in chemical structure to the banned compounds, by which they intended to dominate the world market for refrigerants and propellants.

Discussion

This post and the preceding one, and perhaps a few more to come, strive to point out that humanity benefits from scientific endeavor, in all its varied subject matter.  Scientists work by pursuing characterization of our natural world in an open, unbiased fashion.  The results of scientific investigations and the technologies that result from those studies benefit our lives in innumerable ways.  The progress we humans have made began largely with the industrial revolution in the nineteenth century; it represents a revolutionary departure from the way of life humans had known throughout history.
Telegraph and radio communication point out how scientific development permitted humans to communicate instantaneously across great distances.  Prior to this time human communication traveled primarily only as fast as we could move across land and sea.

The example of CFCs used as refrigerants and propellants likewise shows how research creates new materials intended to have beneficial properties.  The detrimental aspect of their use, promoting the destruction of stratospheric ozone, was unforeseen.  It is thanks to further atmospheric research that the mechanism of ozone destruction was unequivocally identified, and still newer substances that avoid this downside were created.  (Unfortunately, both CFCs and the newer refrigerants are extremely potent greenhouse gases.  It will require still further efforts to overcome this detriment.)
When the drawback of CFCs was identified the powerful corporations that manufactured them sought to diminish the significance in the mind of the public of the scientific research underlying the problem.  But science proceeds in the same way regardless of whether we consider the results to be favorable or harmful.  As shown above, the same scientific process led to potential solutions that overcame the disadvantages. 
The public at large, and corporate entities impacted by research results, cannot cherry pick the results they like and dismiss the ones they don’t.  Rigorous pursuit of the scientific method is the only way forward.
 
© 2017 Henry Auer

Wednesday, May 31, 2017

Science and Technology in Modern Life

Summary. Our daily routines, as we go about our lives in the early 21st century, benefit from revolutionary changes wrought by science and technology in the last 200 years.  As a human endeavor, science consists of a framework of inquiry into the natural world based on open-minded investigation, rather than one in which scientists seek evidence or arguments that support preconceived biases and reject evidence that refutes those preconceptions. 
Certain phenomena came to light in recent decades that adversely affected human health or damaged the environment.  Rigorous scientific study showed that, in each case, human activity involving products or practices of large corporations turned out to be responsible.  Those commercial interests sought to invalidate the scientific results in the minds of the public, rather than continue further research to develop sound solutions to the problems.
We humans have welcomed the advances provided by science and technology.  We cannot justifiably select the science we like and dismiss the science that we don’t.
 
The Daily Routine

Janice gets up in the morning and gets ready to go to work.  She switches on the light and the TV to get the latest news and weather.  For breakfast, she takes a quick snack from the frig and heats it up in the microwave oven.  She gets into her battery-powered electric car, which she bought just a few weeks ago; she’s really impressed with its ease of use and responsiveness on the road.
Once in the office, Janice turns on a networked computer which contains more computing power than the massive main-frame computers of a generation ago.  Her coworkers include many colleagues scattered around the U. S., with whom she effortlessly teleconferences directly from her workspace.  This saves many hours that would be lost in travel time flying to another location for a face-to-face meeting, as well as travel expenses.  Her day is turning out to be highly productive as a result, and saves her company money in the process. 
Back home in the evening, Janice has a dinner composed of foods grown using advances in agriculture that promote higher crop yields; farmers benefit greatly from weather and climate research that helps them plan effectively for the best sowing and harvesting operations. 
                                *                    *                    *                    *
 
The Science and Technology That Janice Likely Takes for Granted

Science.  As a human endeavor, science is a framework of thought and experiment carried out in an open-ended, fact-based fashion.  Scientists seek to make sense of our physical world, both animate and inanimate.  By not having preconceived notions of how they want an investigation to turn out, they probe physical reality in ways that add to our body of knowledge, and that suggest further investigation of questions that may have arisen in earlier work.  New information obtained from these efforts may have direct practical significance having the potential to lead to products that improve our lives.
Technology, or applied science, seeks to optimize characteristics of a system to solve a specific practical problem or to make a specific article with an intended practical use. 
Modern life.  Like Janice, we all benefit from the progress of science and technology in our daily lives, and relish the conveniences and capabilities of new devices or processes as they reach the market.  We, the public at large, accept these with open arms, whether we “understand” the scientific principles that govern their operation or not.  We do not question the truth or validity of the science that undergirds these objects that ease our daily life; indeed, we welcome it with open arms because of the benefits that it brings to our lives.
The scientific basis underlying some of the items and phenomena that Janice encounters in her daily routine are set forth at the end of this post in the Details section.
But some scientific questions, or technological accomplishments, have turned out to provide adverse consequences.  Smoking tobacco became associated with lung disease, including cancer.  Pristine forests and fish in lakes downwind of coal-fired electric generating plants began to die inexplicably, which was ultimately attributed to acid rain from burning coal.  The ozone in the stratosphere, which absorbs harmful ultraviolet radiation in sunlight, became depleted relatively suddenly.  Research showed that certain chemicals developed to serve as propellants in spray cans were responsible. 
Each of these cases is associated with a powerful and lucrative industry.  Careful scientific investigation, using the same conceptual approaches as outlined above, in these cases succeeded in providing a sound scientific basis for the harm that each phenomenon produced.  Yet the industries involved mounted strong public relations campaigns (not based on science) to discredit the science in order to sow doubts about the scientific explanations. 
But we cannot cherry pick which science we like and which science we disavow.  Open-ended, unbiased investigation leads us universally to the scientific progress we welcome and depend on.  In the examples above, scientific study not only explained the origin of the respective adverse effects but also suggested how to remedy the problems.  Thus, here too the scientific method has led to benefits that promote our wellbeing and the integrity of the physical world we inhabit.
Details
Electricity.  The laws of physics governing the interactions between electrically conducting materials (such as metal wires) and magnetic fields were identified during the nineteenth century.  The phenomena are reciprocal: wires moving through a magnetic field generate electrical current, and electrical current flowing through wires generate strong magnetic fields when wound around a core.  In other words, the opposite of generating electricity is the use of wire-wound motors to provide rotational mechanical motion by passing electrical current through them. 
Thomas Edison on the one hand, and Nikola Tesla and Charles Steinmetz on the other, developed differing ways of generating electricity.  Tesla joined the Westinghouse company; their technology won out. Steinmetz joined the General Electric Research Laboratories.
Refrigerators.  The intrinsic physical properties of most gases are such that when the gas is compressed it releases heat to its environment, and when the pressurized gas expands it cools down, absorbing heat from the environment.  Refrigerators work by expanding the gas in the chamber that needs cooling, absorbing heat from the food in the chamber so that the food is cooled.  The refrigerator then compresses the gas outside the chamber, releasing the heat to the environment.  (In recent decades, the reciprocal process has been applied in heat pumps: a gas is expanded in an external environment, absorbing heat, and compressed inside a home, releasing heat to warm the interior space.) 
Microwave ovens.  Physicists whose understanding led to generation of electricity pursued their studies leading to suitable instruments that emit microwaves.  A second group of physicists who developed quantum theory over several decades in the early twentieth century understood that materials could specifically absorb microwaves (among other forms of energy) according to the laws of quantum physics.  Water is one such substance, which is warmed in the process.  A microwave oven generates the specific type of microwave radiation that water absorbs.  Specifically, the oven works by efficiently warming the water contained in various foods using microwave energy.
Electric cars.  Electric cars depend critically on high capacity batteries.  To date these are based on lithium.  The basis for this technology originates in fundamental investigations by chemists, mostly in the nineteenth century.  One contribution was developing the systematics of the chemical periodic table.  Lithium is a very light material, atom for atom, a first physical property favorable for use in batteries.  Second, chemists found that the intrinsic ability of lithium to provide electrical energy is among the highest of all among the chemical elements.  These two inherent physical attributes of lithium make it an optimal choice for use in electric car batteries.  Current research and development is directed to making the batteries as efficient and long-lasting as possible.
Agricultural production.  The Austrian friar Gregor Mendel was the first to discover the laws that govern inheritance of traits in organisms.  Working with pea plants he showed by conventional breeding experiments that intrinsic factors (now called genes) govern how physical traits are passed from generation to generation.  (His work was clearly painstakingly slow, since only one generation of pea plants can grow per year.) 
Agricultural breeders utilize Mendelian genetics to enhance the properties of commercially significant plants and animals.  These properties may include nutritional value, hardiness, and drought and/or heat tolerance, for example.  The results of these projects benefit us, the consumers, as we make our grocery purchases.
The Agricultural Research Service (ARS), a division of the U. S. Department of Agriculture, conducts ongoing characterization and forecasting of near-term weather as well as the longer-term seasonal climate.  Farmers use the information provided by these projects advantageously to plan their activities: planting, fertilizing, and harvesting.  The work of the ARS is summarized in the pamphlet “Science in Your Shopping Cart” .
© 2017 Henry Auer

Friday, April 28, 2017

Sea Level Rise, Due to Human Activity, Imperils Many


Summary. This post discusses three newspaper articles concerning global warming-induced sea level rise, which all appeared in a one-week period about the third week of April, 2017.

Sea level rise is inexorable, already irreversibly “baked in” to the planet’s climate, because melting of ice in the summer season is not restored by new snow and ice in the winter, and because the melted water flows away into the ocean.
Sea level rise is already causing human societal and economic damage around the world.  It will continue unabated, and likely worsen, in future centuries.  To minimize these harms, the world has to minimize greenhouse gas emissions to near zero as soon as possible.  This process would be significantly advanced by adhering to the Paris climate agreement. 
                                          *         *         *         *         *

 




 
The Washington Post reported on April 26, 2017 that the rate of sea level rise now foreseen by scientists is considerably higher than published only four years ago by the Intergovernmental Panel on Climate Change (IPCC) in its Fifth Assessment Report.

The Post article reports that the projections are a collaborative effort among 90 scientists, which was subjected to peer review by 28 other scientists.  Climate models based on two scenarios for continued rates of emission of greenhouse gases to the year 2100 were used for the projections.  One is a moderately stringent policy limiting emission rates.  The second is a scenario based on continued unconstrained emission rates comparable to those that reflect today’s fuel use.  The results are shown in the following table, which also includes the 2013 IPCC projections for comparison.

Scenario
Predicted sea level rise by 2100 [2013 IPCC prediction]
Moderately stringent
At least 52 centimeters (1.7 feet) [32 centimeters (1 foot)]
Unconstrained
At least 74 centimeters (2.4 feet) [45 centimeters (1.5 feet)]

The updated estimates take into account the increased rate of melting of the Greenland Ice Sheet and Antarctic ice shelves recently observed, and expansion of the liquid ocean due to its higher temperature, among other contributing sources.

                                          *         *         *         *         *









This article reports that Tasmania, the island south of the Australian mainland, is already suffering the ravages of sea level rise.  The shoreline is being eroded by rising seas, and trees are being uprooted and falling into the sea.  An abandoned shoreline coal mine is being filled in by the sea.  The article states “The ocean is rising in large part…because people the world over have burned so much coal, pumping planet-warming carbon dioxide into the air. Perhaps a new stone marker [referencing a seaside prisoners’ graveyard] ought to be planted above the eroding mine: Cause, Meet Effect.”  A Tasmanian ecologist stated, with some irony, “It’s a smoking gun for sea-level rise causing an acceleration of erosion.  And it’s coal! Mined for burning!”

The article summarizes manifestations of worsening global warming: “In country after country, managers of national parks and other historic sites are realizing that climate change, with its coastal flooding and erosion, rising temperatures and more intense rainstorms, represents a profound risk to the heritage they are trying to preserve.”  It mentions damage to the Statue of Liberty’s foundation by Hurricane Sandy, loss of most of the glaciers in America’s Glacier National Park, damage to Australia’s Great Barrier Reef due to rising ocean temperature (vindicating a 10-year old prediction), among many other examples.
                                          *         *         *         *         *
https://www.nytimes.com/2017/04/20/magazine/how-singapore-is-creating-more-land-for-itself.html?_r=0













Singapore is an independent island city-nation just off the coast of the southern tip of Malaysia.  It is a thriving metropolis, whose economic base is commerce and the financial industry.  The article notes that Singapore has felt the limitations of its small land area for decades.  This has constrained the ways it can develop additional useful real estate as its fortunes continue to grow. 

In recent years this quandary has been worsened by the encroachment of rising sea levels.  Singapore fortunately has the financial resources artificially to expand its land area by robbing it from the sea.  The image above shows one example.  The city sinks massive ocean-resistant caissons (seen above from the air) into the sea bed surrounding its natural land base, forming void rectangular enclosures.  It then imports huge quantities of sand, or of pulverized rock, and fills in the rectangles to provide new land area which, when completed, will form new surface area for development.  The new land is high enough to withstand sea level rise in the coming years.

The article contrasts the case of affluent Singapore with other, more impoverished, island “micro-nations” that are losing the battle against rising seas.  Solomon Islands is a Pacific Ocean nation on six major islands and several hundred smaller islands, with an area of 11,000 sq. mi.  The article notes that five small islands have already disappeared under rising seas.  Kiribati has bought 6,000 acres of land 1,000 miles away in Fiji for resettlement of its people.  The Maldives is considering a similar purchase in Australia.  Some of the people living on the island micro-nations of Tuvulu, the Marshall Islands and Nauru have already departed.

Discussion

Newspaper reports on sea level rise.  The examples cited in the articles above pinpoint the flooding, and consequent damages, to be expected along coastlines all over the world as sea levels continue rising.  Man-made global warming, the main cause for the rising seas, is unequivocally due to humanity’s burning of carbon-containing fuels for energy, emitting the greenhouse gas carbon dioxide into the atmosphere.  (Other man-made greenhouse gases also contribute to warming.) 
The fundamental problem is that carbon dioxide remains resident in the atmosphere for centuries because there are no natural processes that remove it at the speed and on the massive scale needed to balance the excess amounts that we produce.  As a result, warming will continue worsening until emissions are effectively minimized to near zero. 

Polar melting.  As noted in the Summary, the long-term average temperature of air in contact with the Greenland ice sheet and of ocean water in contact with the Antarctic ice shelves is already warm enough to lead to net melting of these ice reservoirs, raising global sea levels.  We cannot go back to a planetary regime having a lower temperature (which might slow or stop melting of the ice) because of the permanence of carbon dioxide in the atmosphere.  Consequently the sea level is projected to increase for centuries.  Projected higher temperatures will worsen this trend.
The “social cost of carbon” is an economic term for a framework that attempts to place direct financial costs, as well as indirect societal costs, on the consequences of carbon dioxide-induced global warming.  This is necessary because direct costs for the use of carbon-containing fossil fuels stop at the point of sale of the fuel.  The costs incurred as consequences of the resulting global warming are not reckoned in the sale price. 

This may be contrasted, for example, by the costs that residents bear to have their household waste removed by tax-supported services, or the charges that they pay for treatment of their waste water.  The separate expense of handling the waste is directly borne by property owners and/or municipal taxpayers.  No analogous cost for waste treatment is built into the cost structures of fossil fuel-derived energy use.  This is the accounting that enters into pricing the social cost of carbon.
Contributions to the social cost of carbon are seen in the journal snippets presented here.  Singapore is fortunate in having the resources to protect itself from sea level encroachment.  The other oceanic island micro-nations mentioned here do not; they face existential threats in the near future. 

In the U. S., coastal communities in Miami and south Florida, as well as Norfolk, Virginia, now suffer fair weather flooding at high tide, due to higher sea levels, that had not occurred previously.  Their cost of carbon lies in the extensive, expensive barriers they are forced to put in place to minimize the flooding.  Likewise, the New York region is planning to construct similar barriers as a defense against the possibility that future storm surges similar to that of Hurricane Sandy could occur.  All these projects were not foreseen in earlier budgeting processes.  The additional expenses for them become unexpected taxpayer burdens at the state and local levels.  They clearly represent social costs of carbon that are not included in the prices paid for fossil fuels at the time of use.
Conclusion

Three simultaneously published newspaper articles have pointed out the present and future harms to humanity due to sea level rise.  The rising level is due to humanity’s burning of fossil fuels, worsening the carbon dioxide-induced greenhouse effect and producing warmer global average temperatures that melt polar ice caps.
We must work together to minimize future increases in the carbon dioxide burden of the atmosphere in order to slow continued sea level rise.  (The world’s temperature is already too high to stop it outright.)  The Paris climate agreement of 2015 is a good start on this path.  All nations of the world should embrace its provisions, and improve the emission limits it has created.  Rejecting the agreement would be at humanity’s peril.

© 2017 Henry Auer