Good Science vs. “Feel Good” Science
A new scientific truth does not triumph by convincing its opponents and making them see the light, but rather because its opponents eventually die.
—Max Planck, German Nuclear Physicist
Science is organized knowledge. Wisdom is organized life.
—Immanuel Kant
Some say walking, running, or working barefoot, sans shoes, will make you feel good, feel better, feel great.
Really?
Well, there are those who think this is so . . . that doing everything shoeless is the way to go . . . that it just makes good sense. . . . This is called feel good science.
Really?
They think living naturally is living good . . . a reflection of good science . . . and that being shoeless is almost as good as being without clothes.
Really? Are they sure? Because we’ve heard that natives in tropical areas who have gone barefoot their entire lives suffer from some terrible diseases.
Really?
They walk or run around in their bare feet in tropical areas where the soil contains feces . . . of various sorts and sources.
Really?
The feces-contaminated soils contain various pathogenic organisms that enter the skin of the feet and infect humans.
Really?
Locally, the infected humans end up with what they call swollen belly disease or swollen belly syndrome, which causes grossly, distended abdomens.
Really? Sounds a lot like nothing worse than a common beer belly problem.
No; the infection is invariably fatal in infants.
Really? That is bad.
Really!
Introduction
When a national or international issue arises that must be dealt with, generally the problem-solving technique or mitigation process is discussed in terms of justice, morality, and/or science. When issues are confronted, several questions arise. For example: Is the national or international problem of the kind or type that can be dealt with by simply doing what is considered the “right” thing? That is, could the specific decision-making process involved be accomplished based on ethics, rationality, fairness, or rule of law? Or is the issue and its resolution one that requires judgment based on morality rather than justice? That is, is the proper outcome (i.e., the perceived proper outcome) to be achieved as a moral outcome based on action deemed proper at that particular instant or time? When the question is not best resolved based on justice and morality (is there ever such a question?), then may we turn to science for the answer? If so, then do we not have to be careful that the fork in the road we choose to take is based on good science rather than feel-good science? And if this be the case, what is the difference between “good” science and “feel-good” science?
These are questions that must be answered when solutions are sought. In this text we are concerned almost exclusively with science. It is important to note, however, that in any scientific endeavor, what is accomplished or not accomplished can’t be done in a total vacuum—justice and morality will enter the picture sooner or later (let’s hope it is always sooner rather than later).
The point is, whenever a problem arises that must be solved for the common good, then the lines between justice and morality and science may become blurred, to say the least.
In this chapter we use three real-world examples, case studies, of science and scientists at work. We chose these examples because they help to make the point (in our opinion) that in scientific activities nothing is cut and dry; the lines of justice, morality, and science can be and are blurred on a daily basis. The point we are attempting to make is that many people choose to ignore science, brush it away, or simply detest it because science is not always a straightforward path to a concrete or correct decision; science is not a math problem with an absolute, indisputable outcome. And if there is an indisputable outcome, this does not mean we will like it.
Good vs. “Feel Good” Science: The Difference
Before we move on to the case studies, there remains one piece of unfinished business for us to clear up: What is the difference between good science vs. feel-good science? For our purposes in this text we define good science as scientific research that is independently conducted using the scientific method (the scientist’s toolbox) and subjected to peer review. That is, for science to be classified as “good” science, research on whatever issue one is trying to validate must be substantiated.
What about “feel” good science? For our purposes, feel good science is non-objective science. For example, if you think shutting down the smoke-billowing factory next door will solve the world’s air pollution problem that might be an example of “feel-good” science. If you think shutting down the compost factory in your neighborhood will solve an odor-producing problem, the decision to do so might be based on “feel-good” science. If you think the removal of a hydroelectric dam to allow salmon to return to their native waters to spawn is the right thing to do, this may be an example of “feel-good” science. If you are a researcher hired by a particular funding source and your findings favor the position of the funding source, this may be an example of “feel-good” science (some would call this “feel-good” pocketbook or bank account science). This last example, in our opinion, is an example of science at its worst.
In the following case studies, we have presented facts as we see them. We have attempted to make no definitive statements, but we would be wrong in stating that we have not voiced or interjected our opinion, in one way or another. We are human and these are very touchy, emotion-driven subjects. Thus, we provide the following advice to anyone who reads these case studies: In making decisions that affect large numbers of living things and the environment, the decision made should take into account the economic, social, health and safety, moral and ethical, as well as scientific implications of the issue at hand—in attempting to view the big picture, our view should be wide and generalized, not narrow and specialized.
Case Study 6.1: Salmon and the Rachel River1
The Rachel River, a hypothetical river system in the northwestern United States, courses its way through an area that includes a Native American Reservation. The river system outfalls to the Pacific Ocean and the headwaters begin deep and high within the Cascade Mountain Range of Washington State. For untold centuries, this river system provided a natural spawning area for salmon. The salmon fry thrived in the river, and eventually grew the characteristic dark blotches on their bodies and transformed from fry to parr. When the time came to make their way to the sea, their bodies now larger and covered with silver pigment, the salmon, now called smolt, inexorably migrated to the ocean, where they thrived until time to return to the river and spawn (about 4 years later). In spawning season, the salmon instinctively homed their way toward the odor generated by the Rachel River (their homing signal), and up the river to their home waters, as their life cycle instincts demanded.
Before non-Native Americans (settlers) arrived in this pristine wilderness region, nature, humans, and salmon lived in harmony and provided for each other. Nature gave the salmon the perfect habitat; the salmon provided Native Americans with sustenance. Native Americans provided to both their natural world and the salmon the respect they deserved.
After the settlers came to the Rachel River Valley, changes began. The salmon still ran the river, humans still fed on the salmon, but circumstances quickly altered. The settlers wanted more land, and Native Americans were forced to give way; they were destroyed or forcibly moved to other places, to reservations, where the settlers did all they could to erase Native American beliefs and cultural inheritance. The salmon still ran the streams.
After the settlers drove out the Native Americans, the salmon continued to run, for a while. But more non-Native Americans poured into the area. As the area became more crowded, the salmon still ran, but now their home, their habitat, the Rachel River, started to show the effects of modern civilization’s influence. The “civilized” practice and philosophy was “If I don’t want it any more, it’s trash. Throw it away” and the river provided a seemingly endless dump—out of the way, out of sight, out of mind. And they threw their trash, all the mountains of trash they could manufacture, into the river. The salmon still ran.
More time passed. More people moved in, and the more people, the bigger their demands. In its natural course, sometimes the river flooded, creating problems for the settler populations. Besides, everyone wanted power to maintain modern lifestyles—and hydropower poured down the Rachel River to the ocean constantly. So they built flood control systems and a dam to convert hydropower to hydroelectric power. (Funny. The Native Americans didn’t have a problem with flood control. When the river rose, they broke camp and moved to higher ground. Hydroelectric power? If you don’t build your life around things, you don’t need electricity to make them work. With the sun, the moon, and the stars and their healthy, vital land at hand, who would want hydroelectric power?)
The salmon still ran.
Building dams and flood control systems takes time, but humans, though impatient, have a way of conquering and using time (and anything else that gets in the way) to accomplish their tasks, goals, objectives—and construction projects. As the years passed, the construction moved closer to completion, and finally ended. The salmon still ran—but in reduced numbers and size. Soon local inhabitants couldn’t catch the quantity and quality of salmon they had in the past. When the inconvenience finally struck home, they began to ask, “Where are the salmon?”
But no one seemed to know. Obviously, the time had come to call in the scientists, the experts. So the inhabitants’ governing officials formed a committee, funded a study and hired some scientists to tell them what was wrong. “The scientists will know the answer. They’ll know what to do,” they said, and that was partly true. Notice they didn’t try to ask the Native Americans. They also would have known what to do. The salmon had already told them.
The scientists came and studied the situation, conducted testing, tested their tests and decided that the salmon population needed to increase. They determined increased population could be achieved by building a fish hatchery, which would take the eggs from spawning salmon, raise the eggs to fingerling-sized fish, release them into specially built basins, and later, release them to restock the river.
A lot of science goes into the operation of a fish hatchery. It can’t operate successfully on its own (though Mother Nature never has a serious problem with it when left alone), but must be run by trained scientists and technicians following a proven protocol based on biological studies of salmon life cycles.
When the time was right, the salmon were released into the river—meanwhile, other scientists and engineers realized that some mechanism had to be installed in the dam to allow the salmon to swim downstream to the ocean, and the reverse, as well. In salmon lives (since they are an anadromous species—they spend their adult lives at sea but return to freshwater to spawn), what goes down must go up (upstream). Those salmon would eventually need some way of getting back up past the dam and into home water, their spawning grounds. So the scientists and engineers devised, designed, built, and installed fish ladders in the dam (see figure 6.1), so that the salmon could climb the ladders, scale the dam and return to their native waters to spawn and die.
Figure 6.1 Fish ladder at Rocky Reach Dam, Upper Columbia River, Washington State. Photo by Frank R. Spellman.
In a few seasons, the salmon again ran strong in the Rachel River. The scientists had temporarily—and at a high financial expenditure—solved the problem. Nothing in life or in nature is static or permanent. All things change. They shift from static to dynamic, in natural cycles that defy human intervention, relatively quickly, without notice—like a dormant volcano, or the Pacific Rim tectonic plates. In a few years, local Rachel River residents noticed an alarming trend. Studies over a five-year period showed that no matter how many salmon were released into the river, fewer and fewer returned to spawn each season.
So they called in the scientists again. “Don’t worry. The scientists will know. They’ll tell us what to do.”
The scientists came in, analyzed the problem, and came up with five conclusions:
1. The Rachel River is extremely polluted both from point and nonpoint sources.
2. The Rachel River Dam has radically reduced the number of returning salmon to the spawning grounds.
3. Foreign fishing fleets off the Pacific Coast are depleting the salmon.
4. Native Americans were removing salmon downstream, before they even get close to the fish ladder at Rachel River Dam.
5. A large percentage of water is withdrawn each year from rivers for cooling machinery in local factories. Large rivers with rapid flow rates usually can dissipate heat rapidly and suffer little ecological damage unless their flow rates are sharply reduced by seasonal fluctuations. This was not the case, of course, with the Rachel River. The large input of heated water from Rachel River area factories back into the slow moving Rachel River creates an adverse effect called thermal pollution. Thermal pollution and salmon do not mix. In the first place, increased water temperatures lower the dissolved oxygen (DO) content by decreasing the solubility of oxygen in the river water. Warmer river water also causes aquatic organisms to increase their respiration rates and consume oxygen faster, increasing their susceptibility to disease, parasites, and toxic chemicals. Although salmon can survive in heated water—to a point—many other fish (the salmon’s food supply) cannot. Heated discharge water from the factories also disrupts the spawning process and kills the young fry.
The scientists prepared their written findings and presented them to city officials, who read them and were (at first) pleased. “Ah!” they said. “Now we know why we have fewer salmon!”
But their pleasure was short-lived. They did indeed have the causal factors defined—but what was the solution? The scientists looked at each other and shrugged. “That’s not our job,” they said. “Call in the environmental folks.”
The salmon still ran, but not up the Rachel River to its headwaters.
Within days, the city officials hired an environmental engineering firm to study the salmon depletion problem. The environmentalists came up with the same causal conclusions as the scientists (which they also related to the city official), but they also related the political, economic, and philosophical implications of the situation to the city powers. The environmentalists explained that most of the pollution constantly pouring into the Rachel River would be eliminated when the city’s new wastewater treatment plant came on line, and, that specific point source pollution would be eliminated. They explained that the state agricultural department and their environmental staff were working with farmers along the lower river course to modify their farming practices and pesticide treatment regimens to help control the most destructive types of nonpoint source pollution. The environmentalists explained that the Rachel River dam’s present fish ladder was incorrectly configured, but could be modified with minor retrofitting.
The environmentalists when on to explain that the over-fishing by foreign fishing fleets off the Pacific Coast was a problem that the federal government was working to resolve with the governments involved. The environmentalists explained that the state of Washington and the federal government were also addressing a problem with the Native Americans fishing the down-river locations (before the salmon ever reached the dam). Both governmental entities were negotiating with the local tribes on this problem. Meanwhile, local tribes had litigation pending against the state and the federal government to determine who actually owned fishing rights to the Rachel River and the salmon.
The final problem was thermal pollution from the factories, which was making the Rachel River unfavorable for spawning, decreasing salmon food supply, and/or killing off the young salmon fry. The environmentalists explained that to correct this problem, the outfalls from the factories would have to be changed—relocated. The environmentalists also recommended construction of a channel basin whereby the ready-to-release salmon fry could be released in a favorable environment, at ambient stream temperatures, and where they would have a controlled one-way route to safe downstream locations where they could thrive until it was time to migrate to the sea.
After many debates and newspaper editorials, the city officials put the matter to a vote—and voted to fund the projects needed to solve the salmon problem in the Rachel River. Some short-term projects are already showing positive signs of change, long-term projects are underway, and the Rachel River is on its way to recovery.
In short, scientists are professionals who study to find “the” answer to a problem through scientific analysis and study. Their interest is in pure science. The environmentalists (also scientists) can arrive at the same causal conclusions as general scientists, but are also able to factor in socioeconomic, political, and cultural influences as well.
But wait! It’s not over yet. Concerns over disruption of the wild salmon gene pool by hatchery trout are drawing attention from environmentalists, conservationists, and wildlife biologists. Hatchery- or farm-raised stock of any kind is susceptible to problems caused by, among other things, a lack of free genetic mixing, spread of disease, infection and parasites, reinforcement of negative characteristics—when escaped hatchery salmon breed with wild salmon, the genetic strain is changed, diseases can be transmitted . . . many problems arise.
Yes, many problems arise and solutions are constantly sought. When nature’s natural processes are interrupted, changed or manipulated in any way, not only do humans need to adjust to the changes but so does Mother Nature. The question is: Are the human-made changes to natural surroundings a good or bad thing? It depends. Depends on what? Depends on your point of view.
For many, the Rachel River case study probably generates more questions than answers, because there are a number of vignettes within the account; many of which garner separate case studies of their own. However, if we focus on the dam only and its implications, not only for the human inhabitants but also for the natural resources involved, environmental scientists would study the construction of such a human-made structure based on facts, science, and the pros and cons. For example, let’s consider the pros and cons (USGS 2009).
PROS to Hydroelectric Power (as Compared to Other Power-Producing Methods):
• Fuel is not burned so there is minimal pollution
• Water to run the power plant is provided free by nature
• Hydropower plays a major role in reducing greenhouse gas emissions
• Relatively low operations and maintenance costs
• The technology is reliable and proven over time
• It’s renewable—rainfall renews the water in the reservoir, so the fuel is almost always there
CONS
• High investment costs
• Hydrology dependent (precipitation)
• In some cases, inundation of a wildlife habitat
• In some cases, loss or modification of fish habitat
• Fish entrainment or passage restriction
• In some cases, changes in reservoir and stream water quality
• In some cases, displacement of local populations
When you compare the pros and cons of hydroelectric power it sounds great—so why don’t we use it to produce all of our power? Good question. We will leave the answer to the experts—the scientists.
Case Study 8.2: Climate Change2
Humanity is conducting an unintended, uncontrolled, globally pervasive experiment whose ultimate consequences could be second only to nuclear war. The Earth’s atmosphere is being changed at an unprecedented rate by pollutants resulting from human activities, inefficient and wasteful fossil fuel use and the effects of rapid population growth in many regions. These changes are already having harmful consequences over many parts of the globe.
—Toronto conference statement, June 1988
Is global warming a hoax? Is earth’s climate changing? Are warmer times or colder times on the way? Is the greenhouse effect going to affect our climate, and if so, do we need to worry about it? Will the tides rise and flood New York? Does the ozone hole portend disaster right around the corner?
These and many other questions related to climate change have come to the attention of us all. We are inundated by a constant barrage of newspaper headlines, magazine articles, and television news reports on these topics. We’ve seen report after report on El Niño and its devastation of the West Coast of the U.S. (and Peru and Ecuador)—and its reduction of the number, magnitude and devastation of hurricanes that annually blast the East Coast of the U.S.
Scientists have been warning us of the catastrophic harm that can be done to the world by atmospheric warming. One view states that the effect could bring record droughts, record heat waves, record smog levels, and an increasing number of forest fires.
Another caution put forward warns that the increasing atmospheric heat could melt the world’s icecaps and glaciers, causing ocean levels to rise to the point where some low-lying island countries would disappear, while the coastlines of other nations would be drastically altered for ages—or perhaps for all time.
What’s going on? We hear plenty of theories put forward by doomsayers, but are they correct? If they are correct, what does it all mean? Does anyone really know the answers? Should we be concerned? Should we invest in waterfront property in Antarctica? Should we panic?
No. While no one really knows the answers—“we don’t know what we don’t know syndrome”—and while we should be concerned, no real cause for panic exists.
Should we take some type of decisive action—should we come up with quick answers and put together a plan to fix these problems? What really needs to be done? What can we do? Is there anything we can do?
The key question to answer here is “What really needs to be done?” We can study the facts, the issues, the possible consequences—but the key to successfully combating these issues is to stop and seriously evaluate the problems. We need to let scientific fact, common sense, and cool-headedness prevail. Shooting from the hip is not called for, makes little sense—and could have Titanic consequences for us all.
The other question that has merit here is, “Will we take the correct actions before it is too late?” The key words here are: “correct actions.” Eventually, we may have to take some action (beyond hiding in a cave somewhere). But we do not yet know what those actions could be or should be.
From our perspective, one thing is certain; in our college level environmental health courses, we address, sooner or later, global warming and/or global climate change. Through time and experience we have learned (yes, teachers learn, too) that whether we call it global warming, global climate change (humankind-induced global warming, under a broader label), or an inconvenient truth, the topic is a conundrum (riddle, the answer of which is a pun). As such, before diving into the many emotionally-charged, heated class discussion about this “hot” topic (pun intended), we are reminded by two celebrated statements of just how complicated a conundrum can be. These celebrated conundrums are:
What is black and white and read all over? A newspaper.
“Why is a man in jail like a man out of jail?” there’s no answer to it. (Charles Dickens, 1843, Martin Chuzzlewit)
In this section, we discuss global climate change related to earth’s atmosphere and its problems, actual and potential. Consider this: Any damage we do to our atmosphere affects the other three environmental mediums: water and soil—and biota (us—all living things). Thus, the endangered atmosphere (if it is endangered) is a major concern (a life and death concern) to all of us.
The Past
Before we begin our discussion of the past, we need to define the era we refer to when we say “the past.” Tables 6.1 and 6.2 are provided to assist us in making this definition. Table 6.1 gives the entire expanse of time from earth’s beginning to present. Table 6.2 provides the sequence of geological epochs over the past sixty-five million years, as dated by modern methods. The Paleocene through Pliocene together make up the Tertiary Period; the Pleistocene and the Holocene compose the Quaternary Period.
Table 6.1 Geologic Eras and Periods
|
Era |
Period |
Millions of Years Before Present |
|
Cenozoic |
Quaternary |
2.5–present |
|
Tertiary |
65–2.5 |
|
|
Mesozoic |
Cretaceous |
135–65 |
|
Jurassic |
190–135 |
|
|
Triassic |
225–190 |
|
|
Paleozoic |
Permian |
280–225 |
|
Pennsylvanian |
320–280 |
|
|
Mississippian |
345–320 |
|
|
Devonian |
400–345 |
|
|
Silurian |
440–400 |
|
|
Ordovician |
500–440 |
|
|
Cambrian |
570–500 |
|
|
Precambrian |
4,600–570 |
Table 6.2 Geological Epochs Over the Past Sixty-Five Million Years
|
Epoch |
Million Years Ago |
|
Holocene |
01–0 |
|
Pleistocene |
1.6–.01 |
|
Pliocene |
5–1.6 |
|
Miocene |
24–5 |
|
Oligocene |
35–24 |
|
Eocene |
58–35 |
|
Paleocene |
65–58 |
When we think about climatic conditions in the prehistoric past, two things generally come to mind—Ice Ages and dinosaurs. Of course, in the immense span of time that pre-history covers, those two eras represent only a brief moment in time. So let’s look at what we know or what we think we know about the past, and about earth’s climate and conditions. One thing to consider—geological history shows us that the normal climate of the earth was so warm that subtropical weather reached to 60°N and S, and polar ice was entirely absent.
Only during less than about 1 percent of the earth’s history did glaciers advance and reach as far south as what is now the temperate zone of the northern hemisphere. The latest such advance, which began about 1,000,000 years ago, was marked by geological upheaval and (perhaps) the advent of human life on earth. During this time, vast ice sheets advanced and retreated, grinding their way over the continents.
A Time of Ice
Nearly two billion years ago, the oldest known glacial epoch occurred. A series of deposits of glacial origin in southern Canada, extending east to west about 1,000 miles, shows us that within the last billion years or so, apparently at least 6 major phases of massive, significant climatic cooling and consequent glaciation occurred at intervals of about 150 million years. Each lasted perhaps as long as 50 million years.
Examination of land and oceanic sediment core samples clearly indicate that in more recent times (the Pleistocene epoch to the present), many alternating episodes of warmer and colder conditions occurred over the last two million years (during the middle and early Pleistocene epochs). In the last million years, at least eight such cycles have occurred, with the warm part of the cycle lasting a relatively short interval.
During the Great Ice Age (the Pleistocene epoch), ice advances began, a series of them that at times covered over one quarter of the earth’s land surface. Great sheets of ice thousands of feet thick, these glaciers moved across North America over and over, reaching as far south as the Great Lakes. An ice sheet thousands of feet thick spread over Northern Europe, sculpting the land and leaving behind lakes, swamps (remember Yurk and Smilodon), and terminal moraines as far south as Switzerland. Each succeeding glacial advance was apparently more severe than the previous one. Evidence indicates that the most severe began about 50,000 years ago and ended about 10,000 years ago. Several interglacial stages separated the glacial advances, melting the ice. Average temperatures were higher than ours today.
Wait a minute! Temperatures were higher than today? Yes, they were. Think about that as we proceed.
Because one-tenth of the globe’s surface is still covered by glacial ice, scientists consider the earth still to be in a glacial stage. The ice sheet has been retreating since the climax of the last glacial advance, and world climates, although fluctuating, are slowly warming.
From our observations and from well-kept records, we know that the ice sheet is in a retreating stage. The records clearly show that a marked worldwide retreat of ice has occurred over the last hundred years. World famous for its 50 glaciers and 200 lakes, Glacier National Park in Montana does not present the same visual experiences it did a hundred years ago. In 1937, a 10 foot pole was put into place at the terminal edge of one of the main glaciers. The sign is still in place, but the terminal end of the glacier has retreated several hundred feet back up the slope of the mountain. Swiss resorts built during the early 1900s to offer scenic glacial views now have no ice in sight. Theoretically, if glacial retreat continues, melting all of the world’s ice supply, sea levels would rise more than 200 feet, flooding many of the world’s major cities. New York and Boston would become aquariums.
The question of what causes ice ages is one scientists still grapple with. Theories range from changing ocean currents to sunspot cycles. On one fact we are absolutely certain, however; an ice age event occurs because of a change in earth’s climate. But what could cause such a drastic change?
Climate results from uneven heat distribution over earth’s surface. It is caused by the earth’s tilt—the angle between the earth’s orbital plane around the sun and its rotational axis. This angle is currently 23.5 degrees, but it has not always been that. The angle, of course, affects the amount of solar energy that reaches the earth, and where it falls. The heat balance of the Earth, which is driven mostly by the concentration of carbon dioxide (CO2) in the atmosphere, also affects long term climate. If the pattern of solar radiation changes or if the amount of CO2 changes, climate change can result. Abundant evidence that the earth does undergo climatic change exists, and we know that climatic change can be a limiting factor for the evolution of many species.
Evidence (primarily from soil core samples and topographical formations) tells us that change in climate includes events such as periodic ice ages characterized by glacial and interglacial periods. Long glacial periods lasted up to 100,000 years; temperatures decreased about 9ºF, and ice covered most of the planet. Short periods lasted up to 12,000 years, with temperatures decreasing by 5ºF and ice covering 40º north latitude and above. Smaller periods (e.g., the “Little Ice Age,” which occurred from about 1000–1850 AD) had about a 3ºF drop in temperature. Note: Despite its name, the Little Ice Age was a time of severe winters and violent storms, not a true glacial period. These ages may or may not be significant, but consider that we are presently in an interglacial period and that we may be reaching its apogee. What does that mean? No one knows with any certainty.
Let’s look at the effects of ice ages (i.e., effects we think we know about). Changes in sea levels could occur. Sea level could drop by about 100 meters in a full blown ice age, exposing the continental shelves. Increased deposition during melt would change the composition of the exposed continental shelves. Less evaporation would change the hydrological cycle. Significant landscape changes could occur—on the scale of the Great Lakes formation. Drainage patterns throughout most of the world and topsoil characteristics would change. Flooding on a massive scale could occur. How these changes would affect you depends on whether you live in Northern Europe, Canada, Seattle, Washington, around the Great Lakes, or near a seashore.
We are not sure what causes ice ages, but we have some theories (don’t people always have theories?). To generate a full-blown ice age (massive ice sheet covering most of the globe), scientists point out that certain periodic or cyclic events or happenings must occur. Periodic fluctuations would have to affect the solar cycle, for instance; however, we have no definitive proof that this has ever occurred.
Another theory speculates that periods of volcanic activity could generate masses of volcanic dust that would block or filter heat from the sun, thus cooling down the earth. Some speculate that the carbon dioxide cycle would have to be periodic or cyclic to bring about periods of climate change. There is reference to a so-called Factor 2 reduction, causing a 7ºF temperature drop worldwide. Others speculate that another global ice age could be brought about by increased precipitation at the poles due to changing orientation of continental land masses. Others theorize that a global ice age would result if changes in the mean temperatures of ocean currents decreased. But the question is how? By what mechanism? Are these plausible theories? No one is sure—this is speculation. Some would say it is feel good speculation; others say it is real, honest speculation. So, which one is it? We have no clue; we are not sure.
Speculation aside, what are the most probable causes of ice ages on earth? According to the Milankovitch hypothesis, ice age occurrences are governed by a combination of factors: (1) the earth’s change of altitude in relation to the sun (the way it tilts in a 41,000-year cycle and at the same time wobbles on its axis in a 22,000-year cycle), making the time of its closest approach to the sun come at different seasons; and (2) the 92,000-year cycle of eccentricity in its orbit round the sun, changing it from an elliptical to a near circular orbit, the most severe period of an ice age coinciding with the approach to circularity.
So, what does all this mean? We have a lot of speculation about ice ages and their causes and their effects. This is the bottom line. We know that ice ages occurred—we know that they caused certain things to occur (e.g., formation of the Great Lakes), and although there is a lot we do not know, we recognize the possibility of recurrent ice ages. Lots of possibilities exist. Right now, no single theory is sound, and doubtless many factors are involved. Keep in mind that the possibility does exist that we are still in the Pleistocene Ice Age. It may reach another maximum in another 60,000 plus years or so.
Warm Winter
The headlines we see in the paper sound authoritative: “1997 Was the Warmest Year On Record” . . . “Scientists Discover Ozone Hole Is Larger Than Ever” . . . “Record Quantities of Carbon Dioxide Detected in Atmosphere.” Or maybe you saw the one that read “January 1998 Was the Third Warmest January on Record.” Other reports indicate we are undergoing a warming trend, but conflicting reports abound. This section discusses what we think we know about climate change.
Two environmentally significant events took place late in 1997: El Niño’s return and the Kyoto Conference on Global Warming and Climate Change. News reports blamed El Niño for just about anything that had to do with weather conditions throughout the world. Some incidents were indeed El Niño related or generated: the out-of-control fires, droughts, floods, the stretches of dead coral with no sign of fish in the water, and few birds around certain Pacific atolls. The devastating storms that struck the west coasts of South America, Mexico, and California were also probably El Niño related. El Niño’s effect on the 1997 hurricane season, one of the mildest on record, is not in question, either.
Does a connection exist between El Niño and global warming or global climate change? On December 7, 1997, the Associated Press reported that while delegates at the global climate conference in Kyoto haggle over greenhouse gases and emission limits, a compelling question has emerged: “Is global warming fueling El Niño?” Nobody knows for sure because we need more information than we have today. The data we do have, however, suggests that El Niño is getting stronger and more frequent.
Some scientists fear that the increasing frequency and intensity of El Niño’s (records show that two of the last century’s three worst El Niños came in 1982 and 1997) may be linked to global warming. At the Kyoto Conference, experts said the hotter atmosphere is heating up the world’s oceans, setting the stage for more frequent and extreme El Niños. Weather-related phenomena seem to be intensifying throughout the globe. Can we be sure that this is related to global warming yet? No. Without more data, more time, more science (real science), we cannot be sure.
According to the Associated Press coverage of the Kyoto Conference, scientist Richard Fairbanks reported that he found startling evidence of our need for concern. During two months of scientific experiments conducted in autumn 1997 on Christmas Island, the world’s largest atoll in the Pacific Ocean, he witnessed a frightening scene. The water surrounding the atoll was 7ºF higher than average for the time of year, which upset the balance of the environmental system. According to Fairbanks, 40 percent of the coral was dead, the warmer water had killed off or driven away fish, and the atoll’s plentiful bird population was almost completely gone.
No doubt, El Niños are having an acute impact on the globe; however, we do not know if these events are caused by or intensified by global warming. What do we know about global warming and climate change? USA Today (December, 1997) discussed the results of a report issued by the Intergovernmental Panel on Climate Change. They interviewed Jerry Mahlman of the National Oceanic and Atmospheric Administration and Princeton University, and presented the following information about what most scientists agree on:
• There is a natural greenhouse effect and scientists know how it works; without it, earth would freeze.
• The earth undergoes normal cycles or warming and cooling on grand scales. Ice ages occur every 20,000 to 100,000 years.
• Globally, average temperatures have risen 1ºF in the past 100 years, within the range that might occur normally.
• The level of man-made carbon dioxide in the atmosphere has risen 30 percent since the beginning of the Industrial Revolution in the 19th century, and is still rising.
• Levels of man-made carbon dioxide will double in the atmosphere over the next 100 years, generating a rise in global average temperatures of about 3.5ºF (larger than the natural swings in temperature that have occurred over the past 10,000 years).
• By 2050, temperatures will rise much higher in northern latitudes than the increase in global average temperatures. Substantial amounts of northern sea ice will melt, and snow and rain in the northern hemisphere will increase.
• As the climate warms, the rate of evaporation will rise, further increasing warming. Water vapor also reflects heat back to earth.
Global Warming
What is global warming? To answer this question we need to discuss “greenhouse effect.” Water vapor, carbon dioxide, and other atmospheric gases (greenhouse gases) help warm the earth. Earth’s average temperature would be closer to 0 than its actual 60º without the greenhouse effect. But, as gases are added to the atmosphere, the average temperature could increase, changing orbital climate.
How does greenhouse effect actually work? Earth’s greenhouse effect, of course, took its name because of similarity of effect. Because the glass walls and ceilings of a greenhouse are largely transparent to short-wave radiation from the sun, surfaces and objects inside the greenhouse absorb the radiation. The radiation, once absorbed, transforms into long-wave (infrared) radiation (heat), which radiates back from the greenhouse interior, but the glass prevents the long-wave radiation from escaping again and the warm rays are absorbed. The interior of the greenhouse becomes much warmer than the air outside, because of the heat trapped inside.
Earth and its atmosphere undergo a process very similar to this. Short-wave and visible radiation reaching earth is absorbed by the surface as heat. The long heat waves radiate back out toward space, but the atmosphere absorbs many of them, trapping them. This natural and balanced process is essential to supporting our life systems on earth. Changes in the atmosphere can radically change the amount of absorption and therefore the amount of heat the atmosphere retains. In recent decades, scientists have speculated that various air pollutants have caused the atmosphere to absorb more heat. At the local level, with air pollution, the greenhouse effect causes heat islands in and around urban centers, a widely recognized phenomenon.
The main contributors to this effect are the greenhouse gases: water vapor, carbon dioxide, carbon monoxide, methane, volatile organic compounds (VOCs), nitrogen oxides, chlorofluorocarbons (CFCs), and surface ozone. These gases cause a general climatic warming by delaying the escape of infrared radiation from the earth into space. Scientists stress that this is a natural process. Indeed, as noted earlier, if the normal greenhouse effect did not exist the earth would be far cooler than it currently is (Hansen et al., 1986).
Human activities, though, are rapidly intensifying the natural phenomenon which may lead to problems of warming on a global scale. Much debate, confusion, and speculation about this potential consequence is underway, because scientists cannot yet agree about whether the recently perceived worldwide warming trend is because of greenhouse gases, due to some other cause, or whether it is simply a wider variation in the normal heating and cooling trends they have been studying. Unchecked, the greenhouse effect may lead to significant global warming, with profound effects upon our lives and our environment. Human impact on greenhouse effect is real; it has been measured and detected. The rate at which the greenhouse effect is intensifying is now more than five times what it was during the last century (Hansen and Lebedeff, 1989).
Supporters of the global warming theory assume that human activities are significantly altering the earth’s normal and necessary greenhouse effect. The human activities they blame for this increase of greenhouse gases include burning of fossil fuels, deforestation, and use of certain aerosols and refrigerants. From information based on recent or short-term observations, many scientists have observed that the last decade has been the warmest since temperature recordings began in the late 19th century. They can see that the general rise in temperature coincides with the Industrial Revolution and its accompanying increase in fossil fuel use. Other evidence supports the global warming theory. In places that are synonymous with ice and snow—the Arctic and Antarctica, for example—we see evidence of receding ice and snow cover.
Trying to pin down definitively whether or not changing our anthropogenic activities could have any significant effect on lessening global warming, though, is difficult. Scientists look at temperature variations over thousands and even millions of years, taking a long-term view at earth’s climate. The variations in earth’s climate are wide enough that they cannot definitively show that global warming is anything more than another short-term variation. Historical records that have shown that the earth’s temperature does vary widely, as it grows colder with ice ages and then warms again. Because we cannot be certain of the causes of those climate changes, we cannot be certain of what is causing the current warming trend.
Still, debate abounds for the argument that our climate is warming and our activities are part of the equation. The 1980s saw nine of the twelve warmest temperatures ever recorded, and the earth’s average surface temperature has risen approximately 0.6ºC (1ºF) in the last century (USEPA, 2009). An article in Time Magazine (1998) reports that scientists are increasingly convinced that the earth is getting hotter because of the buildup in the atmosphere of carbon dioxide and other gases produced in large part by the burning of fossil fuels. Each month from January through July 1998, for example, set a new average global temperature record, and if that trend continues, the surface temperature of the earth could rise by about 1.8º to 6.3F by 2100. At the same time, others offer as evidence that the 1980s also saw three of the coldest years: 1984, 1985, and 1986. The debate does not end there, however. For example, ever since NASA’s Goddard Institute for Space Studies made a correction to data that seemed to show nine of the ten hottest years in U.S. history occurred since 1995 (turns out it was 3), the more vocal the global warming deniers have been in using this error to prove the whole of global warming induced climate change is a hoax. Others argue that this one faux pas is nothing more than a smokescreen that does not undermine the whole global warming creditability issue.
What is really going on? We cannot be certain. Assuming that we are indeed seeing long-term global warming, we must determine what causes it. But again, we face the problem that scientists cannot be sure of precise causes of the greenhouse effect. Our current, possible trend in global warming may simply be part of a much longer trend of warming since the last ice age. We have learned much in the past two centuries of science, but little is actually known about the causes of the worldwide global cooling and warming that sent the earth through major and smaller ice ages. The data we need reaches back over millennia. We simply do not possess enough long-term data to support our theories.
Currently, scientists can point to six factors they think could be involved in long-term global warming and cooling.
1. Long-term global warming and cooling could result if changes in the earth’s position relative to the sun occur (i.e., the earth’s orbit around the sun), with higher temperatures resulting when the two are closer together and lower ones when they are farther apart.
2. Long-term global warming and cooling could result from major catastrophes (meteor impacts or massive volcanic eruptions) throwing pollutants into the atmosphere that can block out solar radiation.
3. Long-term global warming and cooling could result if changes in albedo (reflectivity of earth’s surface) occur. If the earth’s surface were more reflective, for example, the amount of solar radiation radiated back toward space instead of absorbed would increase, lowering temperatures on earth.
4. Long-term global warming and cooling could result if the amount of radiation emitted by the sun changes.
5. Long-term global warming and cooling could result if the shape and relationship of the land and oceans change.
6. Long-term global warming and cooling could result if the composition of the atmosphere changes.
“If the composition of the atmosphere changes”—this final factor, of course, defines our present concern: Have human activities had a cumulative impact large enough to affect the total temperature and climate of earth? Right now, we cannot be sure. The problem concerns us, and we are alert to it, but we are not certain. Because, again, we do not know what we do not know about global warming or climate change.
However, we can expect, if global warming is occurring, that summers will be hotter. Over the next 100 years, sea level will rise as much as a foot or so. Is this bad? Depends upon where you live. Keep in mind, however, that not only could sea level rise 1 foot over the next 100 years, but it could continue to do so for many hundreds of years. Another point to consider is that we have routine global temperature measurements for only about 100 years. Even these are unreliable, because instruments and methods of observation changed over that course of time.
The only conclusion we can safely draw about climate and climate change is that we do not know if drastic changes are occurring. We could be at the end of a geological ice age. Evidence indicates that during interglacials, temperatures increase before they plunge. Are we ascending the peak temperature range? We have no way to tell. To what extent does our human activity impact climate? Have anthropogenic effects become so marked that we have affected the natural cycle of ice ages (which lasted for roughly the last 5 million years)? Maybe we just have a breathing spell of a few centuries before the next advance of the glaciers. If this is the case, if we are at the apogee of the current interglacial, then we have to ask ourselves a few questions: Is global warming the lesser of two evils when compared to the alternative, global cooling? If we are headed into another glacial freeze, in this era of expanding population and decreasing resources, where will we get the energy (fuel) to keep all of us warm?
Case Study 6.3: Clean-Up of the Chesapeake Bay
Running in length for approximately 200 miles from the Susquehanna River in the north to the Atlantic Ocean in the south, the Chesapeake Bay is the largest estuary in the United States. The Chesapeake Bay’s watershed drains more than 150 rivers and streams and borders the District of Columbia and parts of New York, Pennsylvania, Delaware, Maryland, Virginia, and West Virginia.
The wonders of the Chesapeake Bay can be and have been described in numerous ways. The Bay is one of the most extraordinary places in America. A unique estuary with a vast watershed, the Bay has a tremendous ecological, cultural, historic, recreational, and economic value to the region and the entire country. However, when viewed without rose-colored glasses, the Chesapeake Bay is in trouble. Despite small successes in certain parts of the Bay’s ecosystem, the overall health of the Bay has not improved. The Bay continues to have poor water quality, degraded habitats, and low populations of many species of fish and shellfish.
One of the major pollutants entering Chesapeake Bay is nutrient pollution. Nutrient pollution in the Bay is real and ongoing—the controversy over what is the proper mitigation procedure(s) is intense and never-ending (very political). Nutrients are present in animal and human waste and chemical fertilizers. All organic material such as leaves and grass clippings contains nutrients. These nutrients cause algal growth and depletion of oxygen in the Bay, which leads to the formation of dead zones lacking in oxygen and aquatic life.
Nutrients can find their way to the Bay from anywhere within the 64,000 square mile Chesapeake Bay watershed—and that is the problem. All streams, rivers, and storm drains in this huge area eventually lead to the Chesapeake. The activities of over 13.6 million people in the watershed have overwhelmed the Bay with excess nutrients. Nutrients come from a wide range of sources, which include sewage treatment plants (20–22 percent), industry, agricultural fields, lawns, and even the atmosphere. Nutrient inputs are divided into two general categories, point sources and nonpoint sources.
Sewage treatment plants, industries, and factories are the major point sources (end-of-pipe dischargers). These facilities discharge wastewater containing nutrients directly into a waterway. Although each facility is regulated for the amount of nutrients that can be legally discharged, at times, violations occur.
The largest source of nutrients entering the Bay are from nonpoint sources (general runoff). These nonpoint sources pose a greater threat to the Chesapeake ecosystem, as they are much harder to control and regulate. It is our view that because of the difficulty to control runoff from agricultural fields and the lack of political will and the technical difficulty to prevent such flows, wastewater treatment plants and other end-of-pipe dischargers have become the targets of convenience for the regulators and environmentalists. The problem is that the regulators are requiring the expenditure of hundreds of millions of dollars to upgrade wastewater treatment plants to biological nutrient removal (BNR), tertiary treatment and/or the combining of microfiltration membranes with a biological process to produce superior quality effluent—these requirements are commendable, interesting, achievable, but alone will not lead to restoration of the Bay.
The alternative, the answer to the dead zone problem, to the lack of oxygen problem in various locations in Chesapeake Bay? Take a portion of the hundreds of millions of dollars earmarked for upgrading wastewater treatment plants and build mobile, floating platforms containing electro/mechanical aerators or mixers. These platforms should be outfitted with diesel generators and accessories to provide power to the mixers. The mixer propellers are adjustable; they are able to mix at water depths of 10–35 ft. Again, these platforms are mobile. When a dead zone appears in the Bay, the platforms are moved to a center of the dead zone area and mixers energized at the appropriate depth—the platforms are anchored to the Bay bottom and so arranged to accommodate maritime traffic. The idea is to churn the dead-zone water and sediment near the Bay bottom and force a geyser-like effect above the surface to aerate the Bay water in the dead zone regions. Absolutely nothing adds more oxygen to water than natural or artificial aeration. Of course, while aerating and forcing oxygen back into the water, bottom sediments containing contaminants will also be stirred up and sent to the surface and temporary air pollution problems will occur around the mobile platforms. Some will view this turning up of contaminated sediments as a bad thing. On the contrary, removing contaminants from the Bay through evaporation is a very good thing.
How many of these mobile mixer platforms will be required? It depends on the number of dead zones. Enough platforms should be constructed to handle the warm season’s average number of dead zones that appear in the Bay.
Will this modest proposal actually work? We do not have a clue. This modest proposal is a recommendation based on common sense and not on science. However, this proposal does make more sense than spending billions of dollars on upgrading wastewater treatment plants and effluent quality when this only accounts for 20–22 percent of the actual problem, an effort which we deem as feel-good science. Simply, and sadly, the regulators and others do not have the political will to go after the real culprit in contaminating Chesapeake Bay with nutrients: runoff.
Recall that it was that great mythical hero Hercules, arguably the world’s first environmental engineer, who said that “dilution is the solution to pollution.” Let’s dilute the hell out of Chesapeake Bay dead zones by aerating them.
A Flush by Any Other Name Is a Tax
In 2005, Maryland’s “Flush Tax” was signed into law. The Flush tax implemented a fee of $30 per year on Maryland homeowners to raise money for reducing nutrient pollution to the Bay. This same type of measure was proposed in Virginia but was met with much tougher resistance to passage from citizens and other groups. Many people felt the Flush tax was a band-aid solution to the problem and many advocates and critics were concerned that residents would believe the Flush tax would solve the Bay’s problems—this is not the case, of course; it only addresses 20–40 percent of the problem, if that.
In rebuttal to an op-ed piece supporting approval of the Flush Tax in Virginia, one of the co-authors of this text submitted the following comment:
Chesapeake Bay Cleanup: Good Science vs. “Feel Good” Science
In your article, “Fee to help Bay faces anti-tax mood” (Va. Pilot, 1/2/05), you pointed out that environmentalists call it the “Virginia Clean Streams Law.” Others call it a “Flush tax.” I call the environmentalist’s (and others) view on this topic a rush to judgment, based on “feel good” science vs. good science. The environmentalists should know better.
Environmental policymakers in the Commonwealth of Virginia came up with what is called the Lower James River Tributary Strategy on the subject of nitrogen (a nutrient) from the Lower James River and other tributaries contaminating the Lower Chesapeake Bay Region. When in excess, nitrogen is a pollutant. Some “theorists” jumped on nitrogen as being the cause of a decrease in the oyster population in the Lower Chesapeake Bay Region. Oysters are important to the local region. They are important for economical and other reasons. From an environmental point of view, oysters are important to the Lower Chesapeake Bay Region because they have worked to maintain relatively clean Bay water in the past. Oysters are filter-feeders. They suck in water and its accompanying nutrients and other substances. The oyster sorts out the ingredients in the water and uses those nutrients it needs to sustain its life. Impurities (pollutants) are aggregated into a sort of ball that is excreted by the oyster back into the James River.
You must understand that there was a time, not all that long ago (maybe 60 years ago) when oysters thrived in the Lower Chesapeake Bay. Because they were so abundant, these filter-feeders were able to take in turbid Bay water and turn it almost clear in a matter of three days. (How could anyone dredge up, clean, and then eat such a wonderful natural vacuum cleaner?)
Of course, this is not the case today. The oysters are almost all gone. Where did they go? Who knows?
The point is that they are no longer thriving, no longer colonizing the Lower Chesapeake Bay Region in numbers they did in the past. Thus, they are no longer providing economic stability to watermen; moreover, they are no longer cleaning the Bay.
Ah! But don’t panic! The culprit is at hand; it has been identified. The “environmentalists” know the answer—they say it has to be nutrient contamination; namely, nitrogen is the culprit. Right?
Not so fast.
The local sanitation district and a university in the Lower Chesapeake Bay region formed a study group to formally, professionally, and scientifically study this problem. Over a five-year period, using Biological Nutrient Removal (BNR) techniques at a local wastewater treatment facility, it was determined that the effluent leaving the treatment plant and entering the Lower James River consistently contained below 8 mg/L nitrogen (a relatively small amount) for five consecutive years.
The first question is: Has the water in the Chesapeake Bay become cleaner, clearer because of the reduced nitrogen levels leaving the treatment plant?
The second question is: Have the oysters returned?
Answer to both questions, respectively: no; not really.
Wait a minute. The environmentalists, the regulators, and other well-meaning interlopers stated that the problem was nitrogen. If nitrogen levels have been reduced in the Lower James River, shouldn’t the oysters start thriving, colonizing, and cleaning the Lower Chesapeake Bay again?
You might think so, but they are not. It is true that the nitrogen level in the wastewater effluent was significantly lowered through treatment. It is also true that a major point source contributor of nitrogen was reduced with a corresponding decrease in the nitrogen level in the Lower Chesapeake Bay.
If the nitrogen level has decreased, then where are the oysters?
A more important question is: What is the real problem?
The truth is that no one at this point and time can give a definitive answer to this question.
Back to the original question: Why has the oyster population decreased?
One theory states that because the tributaries feeding the Lower Chesapeake Bay (including the James River) carry megatons of sediments into the bay (storm water runoff, etc.), they are adding to the Bay’s turbidity problem. When waters are highly turbid, oysters do the best they can to filter out the sediments but eventually they decrease in numbers and then fade into the abyss.
Is this the answer? That is, is the problem with the Lower Chesapeake Bay and its oyster population related to turbidity?
Only solid, legitimate, careful scientific analysis may provide the answer.
One thing is certain; before we leap into decisions that are ill-advised, that are based on anything but sound science, and that “feel” good, we need to step back and size up the situation. This sizing-up procedure can be correctly accomplished only through the use of scientific methods.
Don’t we already have too many dysfunctional managers making too many dysfunctional decisions that result in harebrained, dysfunctional analysis—and results?
Obviously, there is no question that we need to stop the pollution of Chesapeake Bay.
However, shouldn’t we replace the timeworn and frustrating position that “we must start somewhere” with good common sense and legitimate science?
The bottom line: We shouldn’t do anything to our environment until science supports the investment. Shouldn’t we do it right?
—Frank R. Spellman 01/05/2005 The Virginian-Pilot
NOTES
1. From F. R. Spellman, and N. E. Whiting (2006). Environmental Science and Technology, 2nd ed. Rockville, MD: Government Institutes.
2. From F. R. Spellman (2009). The Science of Environmental Pollution, 2nd ed.; F. R. Spellman, and N. E. Whiting (2006). Environmental Science and Technology, 2nd ed. Rockville, MD: Government Institutes.
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