Author Archives: bob

Avian Scavengers

A number of birds will scavenge animal remains of all sorts. The most obvious are vultures but also several birds of prey including eagles, crows and even smaller birds such as roadrunners and Jays. This is an important ecological service to clean up what could otherwise be a source of disease. Actually some of the scavenging birds not specially adapted to the lifestyle can become ill from eating carrion.

Some scavenging birds, including our national symbol the bald eagle, are on occasion poisoned with lead bullet fragments in gut piles left over from field-dressed deer. A couple of lead fragments the size of a grain of rice can be lethal to an eagle.

The most commonly encountered scavengers are the Black and Turkey Vultures frequently seen cleaning up road-killed armadillos, possums, skunks, etc. They share some features and are distinct in others. They are both dark birds with bald heads. The lack of a feathered pate was thought to be for hygiene but recently its been suggested to be for thermoregulation. They also share incredibly acidic stomachs. The gastric juices of the Turkey Vulture are more acidic than a car battery and nearly one hundred times as acidic as our stomachs.

Vultures literally turn down their temperature at night by several degrees. In the morning they can be seen with their wings spread wide to the sun. Another method of temperature regulation involves urohidrosis, defecating down their legs in hot weather. This provides some cooling and may also be beneficial in the management of bacteria on their legs.

If approached by a predator or human for that matter they vomit. Some authors suggest this is a defensive action, as their vomitus is so acidic that it can cause burns. Other authors disagree, but all agree that the loss of the vomitus lightens the body weight to aid take-off for escape. Neither variety of vulture has a syrinx so they can only make grunting or hissing noises.

Black Vultures are slightly smaller than the Turkey Vulture. They have a poor sense of smell, therefore they detect a meal via keen eyesight. They will frequently soar higher than other vultures and follow them to a carcass. Black Vultures can show up in large numbers during the birth of livestock. Not only will they consume the afterbirth but also attack and kill newborn animals, and hence can constitute a serious agricultural pest.

Turkey Vultures are slightly larger and have a distinctive red head. Also, they have a somewhat brownish tinge to their feathers when viewed up close. They have the keenest sense of smell among birds. They tend to soar somewhat closer to the ground sniffing constantly for the odor of a carcass.

The importance of vultures was highlighted in India and Pakistan a decade ago. When the vulture population crashed due to the presence of a toxic (to vultures) arthritis drug in cattle carcasses, stray/feral dogs stepped up to fill the niche as scavengers. The dog population rapidly increased as did rabies. It caused a spike in human deaths due to rabies from dog bites.

Dr. Bob Allen, Ph.D., is Emeritus Professor of Chemistry at Arkansas Tech University.

Feedback Accelerates Global Warming

Positive feedback to global warming keeps climate scientists up at night. Feedback can accelerate the rate of change in the climate. The worst-case scenario involves tipping points where the heating of the air and water make parts of the planet uninhabitable.

A frightening irony concerning global warming is the use of air conditioning to combat the heat. We obviously don’t think about cooling our homes and offices right now, but that is part of our problem. Using air conditioning requires power to generate the necessary electricity. The electricity comes to a large degree from burning fossil fuels which contribute to global warming. This short term reaction to a meteorologic phenomenon contributes to a long term climatological phenomenon.

Climate scientists call this positive feedback. Burning fossil fuels to run air conditioners contributes carbon dioxide to the atmosphere which traps heat and makes the planet warmer, which requires more air conditioning, which causes carbon dioxide release which causes more heating which… You get the picture.

In this case, the feedback has a human element. Other feedback loops are purely physical phenomena. These feedback loops add to the complexity of climate modeling. Predictions of future climate rely on computer calculations, the accuracy of which depends on how well the variables in a climate system are understood.

Water vapor in the atmosphere is without question the most important of the global warming feedback loops. Water vapor is a strong greenhouse gas itself; that is, its presence in the atmosphere traps heat and contributes to global warming. The positive feedback comes about because the amount of water vapor in the atmosphere is directly proportional to the temperature of the atmosphere. The hotter the atmosphere the more water vapor, the more water vapor in the atmosphere, the more heat trapped in the atmosphere, the more water vapor in the atmosphere, the more… you get the picture.

When natural gas (methane) is burned it produces carbon dioxide, a major greenhouse gas. Unburned methane released to the atmosphere is itself a potent greenhouse gas. There are vast stores of methane trapped in the permafrost of the tundra and the continental shelf under the oceans. As the planet warms, the permafrost thaws which releases methane. Methane release warms the planet thawing more permafrost which releases more methane which… you get the picture.

The amount of solar heating of the planet is a function of the albedo, the reflectivity of the planet. Sunlight is strongly reflected by snow-covered expanses near the north and south poles. As the climate warms due to global warming, the snow melts exposing soil which is much less reflective.

The less reflective soil traps more heat, warming the planet further, melting more snow, which traps more heat… you get the picture

The same is true of sea ice and the oceans. Ice is more reflective than water. As the ice cover melts, more heat is trapped, as more heat is trapped more ice melts… you get the picture.

A final irony is that as the area of the oceans covered with ice shrinks, it opens more area to exploration and untimely production of crude oil. Burning these fossil fuels adds more carbon to the atmosphere, which warms the planet… I hope you get the picture.

Dr. Bob Allen is Emeritus Professor of Chemistry, Arkansas Tech University.

Minority Rule is the law of the land

In the lifetime of a current college student, a minority of voters have twice selected the president of the United States. In 2000 Al Gore received about half a million more votes than George Bush but Bush was elected president. In 2016, Hillary Clinton got about three million more votes than Donald Trump yet Trump is the president. This has happened on only three other occasions out of forty-five total times.

Currently the Republican party controls fifty-three votes in the Senate, the Democrats and Independents who caucus with them hold forty-seven. Although the Republicans control the majority of votes in the Senate, they represent only forty-four percent of the voters in the United States. We have minority rule in both the presidency and the US Senate.

This disparity in who decides the law of the land was a result of the “Great Compromise” between the power and influence of the small versus large states. The members of the house of representatives often referred to as the peoples’ house, are elected by popular vote. Each House member, regardless of what state they are from, represents about three-quarters of a million people. The Senate is different. Each state gets two senators regardless of size.

At the time of the writing of the constitution, the difference between the populations of the most and least populous states was not as great as today. The ratio of votes in the most populous state, Virginia, was nineteen times the votes in the least populous state, Georgia. Now, California has nominally seventy times as many voters as Wyoming.

The imbalance of votes in the electoral college follow from the imbalance in the Senate. Each state gets electors equal to the number of representatives and senators. An electoral vote is California is worth only one-fifth that of a vote in Wyoming when population is considered.

Compounding the problem is the fact that most states award electoral votes on a winner take all basis. The states get to decide how to apportion popular vote to electors to the electoral college.

Voters in small states have more “electoral oomph” when it comes to electing the president and the composition of the Senate. We currently have minority rule in the presidency, the Senate and the courts due to the responsibility of the Senate to approve federal judges at all levels. Democracy is only found in the House of Representatives. Elsewhere, the minority is thwarting the will of the majority.

Any remedy is hard to come by. Direct election of the president by popular vote would go along way to alleviate the issue of the electoral college but requires amending the constitution. Some argue that the direct election of the President is impractically complex but we do it in every other jurisdiction in the country.

Fixing the disparity in representation in the Senate is even more difficult. Breaking up the big states into smaller pieces by creating senate districts would work. Likewise combining the smaller states into super senate regions is possible. Neither of these is likely – as in now way Jose.

Dr. Bob Allen is Emeritus Professor of Chemistry, Arkansas Tech University.

There’s a Reason for Regulations

In 1516, Duke Wilhelm IV decreed that beer can have only four ingredients: barley, hops, water, and yeast. This regulation, Reinheitsgebot, persists to this day in Germany. The absence of regulations follows the dictum of caveat emptor, the principle that the buyer is solely responsible for ensuring the quality and suitability of goods to be purchased.

If you are buying apples or oranges, it isn’t all that difficult to tell just what you are buying, but in an increasingly complex society with the range of foods and especially drugs, it isn’t so easy. For decades preceding the turn of the twentieth century, the government struggled with protecting us from harm. The Pure Food and Drug Act was passed in 1906 and with it was the creation of the Food and Drug Administration (FDA.)

About this time agriculture was shifting from subsistence farming to larger corporate operations. Increasingly, processing of foods made them less easily identifiable as pure. The muckraking novel “The Jungle” by Upton Sinclair was published in 1905. The novel highlighted the exploitative and unsanitary conditions in the meatpacking industry.

Since that time our food and drug supply have become much safer due to a myriad of regulations by the FDA and the Agriculture Department. Drugs must pass rigorous testing for purity and efficacy and the United States Department of Agriculture (USDA) has been charged with among other things inspecting the meatpacking industry. But with regulations come costs. The fact that meat from infected carcasses doesn’t end up at the grocery store or toxic and carcinogenic molds don’t contaminate peanuts are the result of regulations.

Ronald Regan once famously said let business be business, implying that regulations were stifling commerce. This began the legitimization of deregulations to streamline government involvement in business. The Trump has carried this torch onward. Warning letters, a key tool to keep dangerous drugs or tainted food off the market have fallen by one-third since Trump took office. The rarer but more strict injunctions have also dropped by close to thirty percent.

Deregulation in the meatpacking industry includes allowing faster processing of carcasses and a reduction of the number of USDA inspectors. In some plants, the USDA inspectors have been replaced entirely by plant employees. Do you really think that a meatpacker whose business is to profit from packing meat will view an infected or contaminated carcass with the same critical eye as an inspector paid by the USDA?

The deregulatory zeal goes far beyond food and drugs. The laws and regulations which protect our air and water are under assault. Overturning the Obama era Clean Power Plan means there will be more Mercury in our water, and more Ozone in our air just to name two.

Other actions include allowing greater occupational exposure to toxic substances, and an increase in allowed “accidental release” of toxic materials. Regulations protect us from harm. Business may not like them, and they may cause a small increase in the costs of goods and services but overall they make our society safer. It’s called civilization.

Dr. Bob Allen is Emeritus Professor of Chemistry, Arkansas Tech University.

Ocean Woes

Threats to the biosphere from changes in the oceans are real. Global warming involves not just atmospheric heating but also sea surface warming. About half the increased warming is going to the oceans. This can have wide-ranging effects, with deoxygenation at or near the top of the list of risks.

Henry’s law states that the solubility of gasses in water is inversely proportional to temperature. What this means is that warmer water holds less oxygen. Anglers in Arkansas recognize three distinct kinds of conditions for fishing. Likely the most common fishery in Arkansas is a lake where the water temperature and hence the oxygen content supports fish such as largemouth Bass, sunfish, and the like.

If you are after smallmouth bass you are unlikely to find them in a lake, at least here in Arkansas. Smallmouth bass require a higher oxygen content that is available only in cooler water – usually clear streams that flow fast enough to avoid warming from the sun. It is not uncommon to see smallmouth bass at the cooler upstream ends of creeks and largemouth at the lower, warmer reaches.

Trout are the most demanding in terms of oxygen needs. Trout only thrive in cold water with the highest oxygen concentration. Here is Arkansas that means creeks that get the majority of their flow from springs and the cold tailwaters of impoundments.

The point of this freshwater digression is to point out that the variety and number of fish in a given locale is dependent on water temperature. This is also true in the oceans. There is a reason that megafauna such as whales spend their time in the cold, oxygen-rich waters of the arctic and Antarctic regions – that’s where their food is found in abundance. As the surface of the oceans warm, we should expect changes in where fish and sea mammals alike can survive. Just that sort of change is happening and it doesn’t look good.

Cod are an extremely important commercial fish found in northern regions of both the Atlantic and Pacific Oceans. The importance of this fish alone can not be overemphasized. The coastal regions of northern Europe have depended to a large degree on access to Cod. In the middle of the twentieth century the United Kingdom and Iceland were all but at war over fishing rights to the cod in the north Atlantic near Europe.

The trouble with cod now centers in the North Pacific. Just last week, the Gulf of Alaska was closed to cod fishing for the 2020 season. Stocks have been declining for several years, not from overfishing as occurred in the Grand Banks region of the Atlantic, but from ocean warming. The Arctic is warming much faster than the rest of the planet. Glaciers are receding, arctic ice is diminishing and now fish stocks are dwindling.

In the future, it is conceivable that other more tolerant species of fish can migrate into the warming Arctic waters but for other locales, this isn’t possible. Fish currently in the tropics are already the only species tolerant of the lower oxygen concentrations. Higher temperatures will likely create fish “deserts.”

Dr. Bob Allen is Emeritus Professor of Chemistry, Arkansas Tech University

wind turbine

Size Matters/Wind Turbines

Utilization of the wind for motive power has a long and rich history. Wind-powered sailing vessels were known to ply the Nile river somewhere between 3 and 5 thousand years before the common era (BCE.) Although there is no direct evidence, it is quite possible that sailing craft could have been employed 50 thousand years ago to populate Southeast Asia and Australia.

Stationary power production in the form of lifting water has been dated to a few centuries BCE. Similarly, the wind was used for motive power to grind grain. The use of wind turbines in the Netherlands is legendary. By the 14th century CE, the Dutch were making extensive use of wind turbines to pump water out of the Rhine river basin to recover and maintain dry land. There is a reason this part of Europe is referred to as the “Low Countries.”

The history of wind for the generation of electrical energy is of course much younger. In 1877 Professor James Blythe in Glasgow, Scotland erected a 10-meter tall cloth-sailed wind turbine connected to batteries to light his cottage. Small scale isolated wind-powered electrical production has been in use around the world, including early twentieth-century Midwestern United States. Centralized power delivered via rural electrification in the 30s replaced virtually all small systems.

The modern era of electrical power production began in the 70s following the formation of the Organization of Oil Exporting Countries (OPEC) and subsequent oil price shocks and embargoes. The price of crude oil skyrocketed and shortages of gasoline forced rationing. Later years saw the federal government subsidize wind power with grants and production credits. In 1990 less than one percent of total electrical energy in the United States came from wind. Currently is over seven percent.

The real change in wind power is the size of the turbines themselves. The earliest modern turbines averaged 50 kW, enough to power only a handful of homes. Also, these early turbines were erected on derricks which made for attractive roosting sites birds, especially raptors which led to unacceptable bird kills. The development of monocoque supporting towers have greatly reduced but not eliminated bird kills.

By the start of the twenty-first century, the average turbine size increased 30 fold. These giants produce about 2 MW. Simple calculations show that the midwestern United States could easily produce all the electrical needs of the country except for the distribution problem – most Americans live near the coasts far from the windy central United States.

The real expansion of wind power will occur with off-shore installations. Most off-shore wind is now located in shallow near-coastal areas, but plans for real behemoths on floating towers are in the works. Each of these 20+ MW plants, taller than the Eiffel Tower, can provide energy for tens of thousands of homes.

Both wind energy production and potential continue to grow. The cost of energy production continues to drop and with the advent of large off-shore plants comes more reliability and less intermittency.

A Natural Reaction

Uranium is, of course, the stuff of nuclear reactors and atomic weapons, but it is also part of an intriguing detective story from 1972 that traces back to events two billion years ago – actually 4.5 billion years but at that age who’s counting.

First a little background. For either nuclear reactors or bombs, Uranium 235 is required. This isotope of Uranium has fewer neutrons in the nucleus and is present in small concentrations with U238, the most common isotope. U235 with a natural concentration of 0.72 %, must be concentrated further to make a fissile material that is used in reactors and weapons.

In the early seventies, there was something of a panic in France. France, then as now provides the lion’s share of their electricity from nuclear reactors. At the time France was buying Uranium ore called yellow cake from a mining region in the Oklo River basin in Gabon, Africa. Assays of some shipments showed that the ore was unnaturally low in U235, sometimes by as much as half the expected concentration.

During this period there was much civil unrest as the continent slowly emerged from under the yoke of colonialism. It was feared that Uranium was being stolen by a local tribe with the intention of making a crude bomb. It turns out that the problem was a rather unnatural event in nature. When scientists looked at an analysis of the shipments low in U235 they found several unnatural elements such as Americium, Curium, and Polonium.

These so-called transuranic elements were not known to exist in nature until this discovery. The only place they had been observed was as part of the waste from nuclear reactions, both controlled reactors and bombs. The French had discovered an extremely rare event, a natural nuclear reactor.

When the U235 atoms draw too close together a chain reaction occurs which produces heat. That heat is used to produce steam in nuclear reactors. In the process, the U235 reacts to turn in to other elements. Exactly the same process occurred in the Oklo River basin.

Over two billion years ago there was scant free Oxygen in the air, then along came cyanobacteria. Gradually the atmosphere changed and many minerals reacted with Oxygen. All the rusty looking soil across the planet is due to Iron Oxide which formed during this period.

In the case of Uranium, it became more water-soluble as it oxidized. In locations with rich Uranium deposits such as the Oklo River basin, this allowed for the dissolved Uranium to accumulate in shallow lakes. Over time some of these lakes became isolated and as the lakes evaporated the Uranium was concentrated. Another bacteria capable of taking the Oxygen away from the Uranium Oxide reduced the solubility even further.

When the Uranium in these pools reached critical mass – the concentration necessary for a chain reaction – the U235 fissioned producing heat and forming the transuranic elements. As the reactions proceeded the U235 was depleted. Altogether sixteen different sites in the river basin have been found to have undergone fission reactions. To date this is the only known place on earth where a natural fission reaction has occurred.

Dr. Bob Allen is Emeritus Professor of Chemistry, Arkansas Tech University.

Pumpkin Eater

Other than the turkey itself, no other foodstuff says Thanksgiving like pumpkin. Notably, both the turkey and the pumpkin are native to the Americas. Turkeys and pumpkins both were supposedly components of that first meal shared by native Americans with the colonists. Pumpkin pie is so ubiquitous that the combination of spices used to flavor it – cinnamon, nutmeg, cloves, and ginger – have come to be called pumpkin spice, and that flavor shows up in a number of the products we consume this time of year.

Pumpkins are in a large family, Cucurbita, with over 900 species. These species include gourds, winter and summer squash, all sorts of melons, and even cucumbers. Native Americans over thousands of years transformed what we know today as a Pumpkin from a tennis ball sized gourd with a very bitter taste.

As are so many other things we eat, pumpkins were made palatable via selective breeding. Pumpkins originated in Central America, and seeds of domestic Pumpkins dated to 8,000 years Before the Current Era (BCE) have been found in the highlands of Mexico. Softer, sweeter pumpkins were chosen from the wild or selected from purposeful plantings. This process continues to this day. Burpee’s Catalog offers 26 varieties of pumpkins.

The story of the post-human-manipulation pumpkin is interesting in and of itself but the natural history of the pre-humanpumpkin is also exciting. There is evidence that megafauna: mastodons, mammoths, giant sloths, etc., were an important part of the pumpkin’s story. Deposits of mastodon dung dated to 30,000 years ago contained squash seeds. The survival of the seeds after passage through the digestive tract of the megafauna provided a means of dispersal and fertilization which is valuable mechanism for evolutionary success.

It is quite likely that the bitter taste is important to this story. The bitterness of the ancestral pumpkin was due to compound called Curcubitacin which not only imparted the bitter taste but was also toxic. Plants and animals have been duking it out over billions of years. Plants have evolved to produce a great number of toxins to prevent herbivores from damaging their reproductive parts or seeds.

Had small mammals eaten these squash, they surely would have also eaten the nutritious seeds. And here is where the bitterness comes in. Modern gene sequencing has shown that among mammals at least, there is a correlation between sensitivity to the bitter taste and size. Sampling animals from rodents to elephants has shown that the smaller the animal, the greater the sensitivity to bitterness. Small mammals such as rodents avoided the bitter plants leaving them to the megafauna.

The effect is that early pumpkins allied with the megafauna to promote a type of mutualism. The megafauna got the benefit of the pumpkin as food while the pumpkin benefited by dispersion/fertilization. The demise of the megafauna would have been a problem for pumpkins, but luckily humans came along and partnered up. Pumpkins are now cultivated around the world, a range far in excess of its ancestral home.

Dr. Bob Allen is Emeritus Professor of Chemistry, Arkansas Tech University.

Energy Plus Agriculture

All human endeavors have some impact on the environment be it good, bad, or otherwise. This is especially true when it come to power production. Relatively cheap and available power has transformed the human landscape. Life expectancy more than doubled since the advent of the industrial revolution begun late in the 18th century. The cheap power aided agriculture by greatly increasing productivity and reducing the threat of starvation. Less demand for agricultural labor freed the attention of others to expand an understanding of health care.

However, the negative impacts of the utilization of fossil fuels – coal, oil, and gas – are legendary. In December, 1952 a combination of weather conditions and pollutants from coal smoke killed thousands of Londoners. Oil slicks on the Cuyahoga River in Cleveland, Ohio frequently caught on fire throughout the 1960s. Re-injection of fracking wastes from the production of natural gas has been blamed for recent earthquakes. And then there is global warming and climate change which threaten the planet.

So, power is good, but power from fossil fuels is not so good. The obvious answer is power without the negative impacts imposed by fossil fuels. All the alternatives have some negative impacts but in aggregate, are an improvement.

An interesting combination of technologies is referred to as agrivoltaics, the pairing of agriculture with solar panels to increase farm income. The results from studies here in the United States and Australia are quite surprising.

At first blush one would think that putting solar panels on a pasture would produce energy from the solar panels but the shading would decrease forage production. A study in Australia found just the opposite. Properly spaced and elevated solar panels actually increased forage production. Partial shading was not a significant issue, but the presence of the solar panels reduced loss of soil moisture.

At the same time that the panels help agriculture, agriculture helps the panels. Transpiration of the biomass under the panels lowered the temperature around the panels and increased solar electric output.

An unanticipated benefit was found in a study in Oregon. Panels installed on a pasture on a sheep farm greatly reduced predation of lambs by eagles. The panels provided shelter from eagle strikes.

In a related vein, the marriage of solar panels and water bodies is synergistic. In arid lands evaporation from a reservoir is significant issue. Placing solar panels on pontoons close to the water’s surface reduces evaporation and as before, the cooling effect of the water increases energy production.

Even without the benefit of increased energy production, solar panels can be beneficial. Rooftop systems reduce exposure of homes to harsh weather. Or how about decking over asphalt parking lots? The shade provided will help cool the lot and at the same time provide electrical energy to perhaps charge electric vehicles while the owners shop.

With forethought, energy production from solar panels can be enhanced and simultaneously provide beneficial effects to land use.

Dr. Bob Allen is Emeritus Professor of Chemistry, Arkansas Tech University.

Leaving Paris

President Trump campaigned on the denial of climate change, calling it a Chinese hoax. Upon election, he announced that the United States would be withdrawing from an agreement reached among every nation on earth. Despite the world’s scientists, the world’s scientific organizations, and the world’s governments agreeing that climate change is an existential threat to humanity and our environment, the government of the United States says no.

Despite polling showing the majority of us agree that climate change is occurring and action needs to be taken and despite the fact that the size of this majority is growing over time, the Trump administration continues to roll back regulations meant to combat global warming.

The full name of the agreement is “the Paris Agreement under the United Nations Framework Convention on Climate Change. “ It is also referred to as COP21, the 21st Conference of Parties. This agreement was designed to improve upon and replace the rather ineffectual Kyoto Protocol from 2005.

The agreement is an international treaty that has been ratified by UN members representing nations that produce in aggregate over 55 percent of greenhouse gas emissions. This means very few nations representing major emitters could effect ratification of the treaty: China, USA, India, Russia, and Japan would be all that is necessary. In fact, 197 countries have ratified the treaty.

The treaty created individualized targets called Nationally Determined Contributions (NDCs) for greenhouse gas reductions. The developed nations have targets with steeper reduction curves compared to the developing world. The argument is the countries of the developed world are principally responsible for the excess of greenhouse gasses and therefore should bear the lion’s share of the reductions.

President Trump formally notified the international community this week that we will withdraw from the agreement next fall. The date for the formal withdrawal is one day after the 2020 elections. Even if he loses his bid for re-election he is still president until the inauguration of a new president.

Since at least the end of World War II, the United States has been the world leader in science and technology and a moral guidepost for the world. By disengaging from this treaty we are telling the rest of the world that we don’t care. By abandoning the objective of lessening of the risk of climate change also means that we will be less focused on science and technology to achieve the end.

The solution for addressing climate change is a moral one – we need to recognize reality, and a scientific and technological one – developing new ways of producing the energy we need to power our society with less greenhouse gas emissions.

China is the world leader in installing wind and solar power sources in total. On a per-capita basis, Denmark is the leader in wind and Germany for solar.

We literally stand along among the nations of the world in our direction of change. As the world moves to cleaner renewable energy our government is moving to subsidize fossil fuel utilization.

Dr. Bob Allen is Emeritus Professor of Chemistry, Arkansas Tech University.