Part 3: Environmental Debates
Attached to this project assignment are the basics of three ongoing environmental debates. Each attempts to present a key issues, pertinent facts, and resources to explore both sides of the debate. Select the debate that is most interesting to you, and write a short essay (1 page or less would be ideal) taking a position on the debate – which side do you agree with and why?
Environmental Debate: Are Humans Affecting the Carbon Cycle? Issues and Background
“[T]he increases in atmospheric carbon dioxide (CO2) and other greenhouse gases during the industrial era are caused by human activities. As a result, biogeochemical cycles have been perturbed significantly.” IPCC Annual Report, 2007, Executive Summary and FAQ 7.1 (http://www.ipcc.ch/publications_and_data/ar4/wg1/en/ch7s7-es.html)
“There is no direct scientific evidence that man-made greenhouse gases are causing catastrophic global warming. Instead, the world has been captured by the ideology of Climatism.” Steve Goreham, p. 2 in The Mad, Mad, Mad World of Climatism, 2013, New Lenox Books.
Over eons, the amount of carbon in each of Earth’s four reservoirs (land, ocean, atmosphere and organic matter) has been relatively constant. Most carbon is stored in the Earth—some as fossil fuels such as coal, petroleum, and natural gas. The oceans are huge “sinks” for carbon—they hold fifty times more carbon dioxide (CO2) than the atmosphere because CO2 is very soluble in seawater. Carbon flows between the Earth’s reservoirs at different rates, depending on a variety of complex processes, including temperature. Warm ocean water holds less CO2 than cool water, and the atmosphere during an ice age contains 40% less CO2 than during warmer times.
Over the last 12,000 years, atmospheric CO2 levels have been stable—between 260 and 280 parts per million (ppm). However, since the mid-1700s, which marked the beginning of the Industrial Revolution, humans have burned fossil fuels to run machines used in agriculture, homes, transportation, and industry. Burning fossil fuels transfers carbon that had been stored in the ground for millions of years to the atmosphere. We have also burned and cut vast areas of forests, which transfers carbon from organic material to the atmosphere. Has the transfer of billions of tons of carbon from the Earth to the atmosphere had any effect on the carbon cycle? Where does all this excess carbon end up? Should we care if the atmosphere has more CO2?
Scientists are concerned that increased atmospheric CO2 (and other gases) can trap additional solar energy, which will lead to changes in the Earth’s climate. The Intergovernmental Panel on Climate Change (IPCC) was formed to provide a clear, scientific view on climate change and its effects. Thousands of scientists from all over the world voluntarily contribute to the IPCC’s work, including publishing peer-reviewed Assessment Reports. Over 97% of the world’s climate scientists agree that climate-warming trends over the past century are very likely due to human activities, and most leading scientific organizations endorse this position. However, there is significant opposition from many people about whether climate change is happening, and—if it is—whether humans are causing this change. The following questions examine some controversies about human effects on the carbon cycle.
Is CO2 increasing in the atmosphere? The IPCC’s Fourth Assessment Report (2007) stated that atmospheric CO2 concentrations are 100 ppm above their pre-industrial level (280 ppm). It takes 5,000 to 20,000 years to change CO2 levels by 100 ppm, but human activities increased CO2 levels this much in only 120 years! The rate of emissions is also increasing: half of the 100
ppm increase has occurred in the last 30 years, and from 1995 to 2007, the growth rate of 2 ppm/yr was the fastest on record, and is still increasing. CO2 atmospheric concentrations reached 400 ppm in 2013, the highest level in more than 3 million years. Climate change deniers say that data about CO2 levels are not reliable. They state that computer models provide only “estimates” and data are taken at sporadic locations across the globe. Climate scientists state that the data are accurate because atmospheric CO2 concentrations are uniform around the globe, so a few surface monitoring stations can accurately estimate atmospheric CO2, and computer models are much more accurate than in the past.
Is the additional 100 ppm of CO2 important? Climate deniers say that only 3% of the CO2 in the atmosphere is due to humans, and such a small percent increase is insignificant. The problem is that the reservoirs cannot absorb all of this additional carbon. In fact, the last time the atmospheric CO2 concentrations reached 400 ppm, horses and camels lived in the Arctic, seas were at least 30 feet higher, and the planet was warmer by about 2 to 3 degrees C (3.6 to 5.4 degrees F). It is obvious that a 100 ppm CO2 increase has very significant climate effects.
Are increased atmospheric CO2 levels due to human activities? Climate change deniers say the extra CO2 comes from oceans, volcanoes, or natural cycles. The IPCC says humans have caused the increased levels. As it turns out, not all CO2 is the same; carbon exists in various forms (isotopes). Fossil fuels contain less C-13 (a heavy isotope of carbon) than oceans, or volcanic or geothermal emissions. The ratio of atmospheric C-13 to other carbon isotopes is declining, showing that the added carbon comes from fossil fuels and vegetation because if the carbon came from the oceans, there would be more C-13 in the atmosphere, not less. Carbon-14, which is in atmospheric CO2 but not in fossil fuels, was also decreasing (until atmospheric testing of nuclear weapons), which showed that fossil fuel carbon is being added to the atmosphere.
What happens to the CO2 after it enters the atmosphere? The Earth can absorb some excess CO2. Since 1959, over 45% of the CO2 released has “disappeared.” Where did it go? Of the 7.2 GtC/yr (gigatonnes, or billion tonnes of carbon per year) humans emitted each year from 2000 to 2005, about 4 GtC accumulated in the atmosphere, 2 GtC entered the ocean, and 2 GtC entered the land and vegetation. Climate deniers say that human CO2 emissions will replace CO2 emissions that naturally leave the ocean. But the IPCC reports that the amount of CO2 absorbed by the ocean is limited, and will actually decrease because warm oceans are less able to absorb CO2.
How long does CO2 stay in the atmosphere before it transfers to another reservoir? Climate deniers say that CO2 is not a problem since it only stays in the atmosphere for five to six years. This is partly true—a molecule of CO2 leaves the atmosphere by changing places with one in the ocean. But this is not the important point. Climate change is due to the extra CO2 being pumped into the atmosphere, so the question is: How long will it take for all of this extra CO2 to be removed? Experts predict it will take 30 years to remove 50% of the excess CO2, centuries to remove the next 30%, and thousands of years to remove the last 20%—and this is only if we stop emitting excess CO2 now.
Understanding the carbon cycle, and how humans affect it, can help us understand the potential effects of a climate that is changing due to human activities. But first we must decide who we are going to trust, and what data we will believe.
Primary Resources and Data
Intergovernmental Panel on Climate Change, Fourth Assessment Report: Climate Change. 2007. The Executive Summary and Chapter 7, Section 3 gives excellent information on the carbon cycle and the climate system. (http://www.ipcc.ch/publications_and_data/ar4/wg1/en/ch7s7-es.html)
Climate Change: Picturing the Science. 2009. W.W. Norton Pub. 305 pages. ISBN: 9780393331257. Dr. Gavin Schmidt, a climate scientist and climate modeler at NASA’s Goddard Institute for Space Studies (GISS) has published over 70 refereed articles in scientific journals. Joshua Wolfe is an editor for RealClimate.org, an internally peer-reviewed blog that provides commentary on climate science for the public and journalists.
The Mad, Mad, Mad, World of Climatism. 2013. New Lenox Books. 246 pages. ISBN: 9780982499696. Climate denier Steve Goreham has an M.S. in Electrical Engineering and an MBA. He is a policy advisor for the Heartland Institute, which was described by The Economist (May 26, 2012) as the “world’s most prominent think tank promoting skepticism about man- made climate change.”
Different Perspectives in the Debate
Dire Predictions: Understanding Global Warming. The Illustrated Guide to the Findings of the IPCC. 2009. DK Publishing. 208 pages. ISBN: 9780136044352. Dr. Mann is an author and reviewer for the IPCC’s Assessment Reports, has authored over 100 peer-reviewed publications, and co-founded RealClimate.org. Dr. Kump has over 75 peer-reviewed publications, and serves with the National Academy of Science.
Robert Kunzig, Climate Milestone: Earth’s CO2 Level Passes 400 ppm. National Geographic News, May 9, 2013 (http://news.nationalgeographic.com/news/energy/2013/05/130510-earth- co2-milestone-400-ppm).
Tripati, A. K., C. D. Roberts, and R. A. Eagle. 2009. Coupling of CO2 and Ice Sheet Stability Over Major Climate Transitions of the Last 20 Million Years. Science 326:1394-1397. (Published online: 10/8/2009; http://www.sciencemag.org/content/326/5958/1394.full). This is an example of a scientific, peer-reviewed paper where the authors describe how they estimated pCO2 (the partial pressure of CO2) during major climate transitions of the past 20 million years.
Skeptical Science website (www.skepticalscience.com). Australian blogger author John Cook created this website in 2007 to publish articles related to climate science, and provide a database
of rebuttals to arguments against climate change. The information from peer-reviewed scientific papers that challenge skeptics’ arguments is easily understandable.
Environmental Debate: Do Antibiotics in Livestock Harm Humans? Issues and Background
“Antimicrobial resistance is a public health problem of growing urgency. Mounting evidence is confirming the view, long held in the public health community, that antimicrobial use in animals can substantially reduce the efficacy of the human antimicrobial arsenal. Now is the time to act to curb the overuse of antimicrobials in animals.” Union of Concerned Scientists (Hogging It: Estimates of Antimicrobial Abuse in Livestock. 2001. M. Mellon, C. Benbrook, and K. L. Benbrook; http://www.ucsusa.org/assets/documents/food_and_agriculture/hog_front.pdf
“Animal antibiotics make our food supply safer and people healthier [and] are a critical tool to prevent, control and treat disease in animals. In doing so, they also reduce the chance of bacterial transmission from animals to humans [and produce] the safest food possible.” The Animal Health Institute; (www.ahi.org)
Imagine that you get pneumonia and end up in the hospital, but the antibiotics you are given no longer work. Or imagine that a loved one is suffering from malaria, but none of the anti-malaria drugs being given are working. Or suppose terrorists release anthrax, but antibiotics cannot stop people from getting sick or dying. These terrifying scenarios can happen because a growing number of bacteria and other pathogens are becoming resistant (“superbugs”) to our most powerful antibiotics. Antibiotic resistance develops in two ways: when medicines are overused or used incorrectly, and from increased antibiotic use in animals we raise for food. Bacteria and other pathogens that become resistant to the antibiotics used in livestock can remain on meat that is spread to humans when handled or not cooked properly. If a person gets sick or develops an infection, antibiotics will not work on the drug-resistant bacteria. As antibiotics lose their effectiveness, doctors will be less able to fight infections, diseases, or infectious complications due to chemotherapy, dialysis, organ transplants and surgery. Alternate antibiotics, if they are even available, can be more dangerous, expensive and less effective. The CDC believes that antimicrobial resistance is one of our most serious health threats—affecting 2 million people in the U.S., and killing 23,000 each year. Longer hospital stays, costlier treatments and increased disabilities cost $20 billion each year in healthcare costs, and $35 billion in lost productivity.
Why do we give antimicrobials or antibiotics to the animals we raise for food? Antimicrobials kill or inhibit microorganisms, and antibiotics are antimicrobials produced by one microorganism that kills or inhibits other microorganisms. Many antimicrobials used on livestock, such as tetracycline, bacitracin, penicillins and sulfonamides are used in humans to treat pneumonia, scarlet fever, rheumatic fever, venereal diseases, plague and anthrax. Antimicrobials are used in livestock to control a disease outbreak and to treat sick animals. But why are antimicrobials also used “non-therapeutically” to prevent disease, and promote animal growth and feed efficiency?
In 2011, the average American ate 98 pounds of meat, 603 pounds of dairy products, 71 pounds of poultry, and 241 eggs. Family farms are being replaced by Concentrated Animal Feeding Operations (CAFOs)—“factory farms” that contain thousands of animals. Over 1,000 U.S. farms have more than 5,000 cattle—one corporation alone owned ten feedlots with 520,000
cattle. In 2011, 34 million cows were slaughtered, producing 25.6 billion pounds of meat. Many of the nation’s 9 billion chickens slaughtered each year are kept in “grower houses,” windowless sheds housing up to 20,000 chickens each. Housing thousands of animals in small areas virtually guarantees disease outbreaks, which require antibiotics to prevent or treat.
Eighty-four percent of swine, cattle and sheep facilities give antibiotics in feed or by injection to promote rapid growth. The Union of Concerned Scientists (UCS) states that each year, U.S. producers give cattle, swine and poultry over 24.6 million pounds of non-therapeutic antimicrobials, which accounts for 70% of total antimicrobial use, and is eight times higher than human medicine. The Animal Health Institute (AHI) disagrees, saying that 17.8 million pounds of antimicrobials are used yearly, which is 40% of all antimicrobial use, and 87% of this was for therapeutic purposes.
Livestock industry representatives say that there is no scientific evidence that antibiotics used in food animals contribute to bacterial resistance in people. However, resistant strains of Salmonella, Campylobacter, and E. coli—which are associated with increased numbers of sick patients, bloodstream infections and death—have been found in contaminated meat. The USDA issued a fact sheet linking drug use in animals and methicillin-resistant Staphylococcus aureus (MRSA) infections in humans. In 2011, 47% of 136 samples of beef, chicken, pork and turkey were contaminated with strains of drug-resistant Staphylococcus aureus, which causes staph infections that annually kill 11,000 people. Although testing suggested the animals were the source of contamination, some say that the bacteria could have come from food handlers.
In 2010, the FDA urged the meat industry to cut back on antibiotic use, but has come under heavy pressure from the powerful livestock industry to refrain from increased antibiotic regulation and restrictions. Advocates of antimicrobial use in livestock point to CDC data that show a 20% decrease in U.S. cases of foodborne illness in the last ten years. The AHI says that people are more likely to die from a bee sting than from resistant bacteria in meat or poultry. The National Cattlemen’s Beef Association says antibiotic resistance is a complex issue, while the National Chicken Council states that antibiotics are used sparingly. National Turkey Federation representatives said that more turkeys would get sick without antibiotics. Representatives from the National Milk Producers Federation say that antibiotics reduce harmful bacteria, while the National Pork Producers Council blames doctors who overprescribe antibiotics. Drug manufacturers say that cooking destroys bacteria, and dead bacteria cannot transmit antibiotic resistance. The American Veterinary Medical Association (AVMA) is against further restrictions on antimicrobials in livestock, and says that banning non-therapeutic use of antimicrobials will not reduce antimicrobial resistance. However, after Denmark banned antibiotics in food animal production, antimicrobial resistance in many bacterial species (including Campylobacter and Enterococci) was reduced.
Reports from the CDC, the NAS, and the Pew Commission on Industrial Farm Animal Production state clearly that using antibiotics for promoting growth in food animals is unnecessary, and the practice should be phased out. Additionally, over 300 organizations from health, consumer, agricultural, environmental, humane, and other interests support efforts, including legislation, to phase out non-therapeutic use of medically important antibiotics in farm animals.
Primary Resources and Data
2007 Census of Agriculture, U.S. Data, National Agricultural Statistics Service gives fascinating information on the state of U.S. agriculture (the 2012 Census will be published soon). http://www.agcensus.usda.gov/Publications/2007/Full_Report/Volume_1,_Chapter_1_US/
H.R. 965, PAMTA (‘‘Preservation of Antibiotics for Medical Treatment Act of 2011’) was introduced in the House of Representatives to amend the Federal Food, Drug, and Cosmetic Act to preserve the effectiveness of medically important antibiotics used in the treatment of human and animal diseases, but was not enacted. (http://www.govtrack.us/congress/bills/112/hr965)
Putting Meat on the Table: Industrial Farm Animal Production in America. 2008. A Report of the Pew Commission on Industrial Farm Animal Production, by the Pew Charitable Trusts and Johns Hopkins Bloomberg School of Public Health. This report examined the U.S. system of food animal production and its impact on public health, the environment, animal welfare, and rural communities. (http://www.pewtrusts.org/uploadedFiles/wwwpewtrustsorg/Reports/Industrial_Agriculture/PCI FAP_FINAL.pdf)
Antibiotic Resistance Threats in the United States, 2013. U.S. Department of Health and Human Services. Centers for Disease Control and Prevention. April 23, 2013. 112 pages. This report provides information on antibiotic resistance. (http://www.cdc.gov/drugresistance/threat-report-2013/pdf/ar-threats-2013-508.pdf#page=5)
The Massachusetts Society for the Prevention of Cruelty to Animals (MSPCA) works to “ensure the humane treatment of animals.” (http://www.mspca.org/programs/animal-protection-legislation/animal-welfare/farm-animal- welfare/)
The American Veterinary Medical Association’s (AVMA) website provides its perspective on whether antimicrobial use in food animals should be a cause for concern in human health. (https://www.avma.org/KB/Resources/FAQs/Pages/Antimicrobial-Use-and-Antimicrobial- Resistance-FAQs.aspx)
The Animal Health Institute (AHI) “represents companies that develop and produce the medicines that help our pets live longer, healthier lives and contribute to safe food by keeping food animals healthy.” Its website gives information about animal antibiotics from its perspective.http://www.ahi.org/issues-advocacy/animal-antibiotics/
Different Perspectives in the Debate
Food Politics: What Everyone Needs to Know. 2010. Oxford University Press, 240 pages. ISBN:0199322384. Robert Paarlberg’s book presents a broad overview of many issues facing food production, including food prices, hunger, obesity, and food safety.
The Ethics of What We Eat: Why Our Food Choices Matter. 2007. Rodale Books, 336 pages. ISBN:1594866872. This book, written by famous ethicist Peter Singer and co-author Jim Mason, explores the impact our food choices have on humans, animals and the environment, and maintains that “you can be ethical without being fanatical.”
The Small-Scale Poultry Flock: An All-Natural Approach to Raising Chickens and Other Fowl for Home and Market Growers. 2011. Chelsea Green Publishing: 416 pages. ISBN:1603582908. In this encyclopedia of chicken (and other fowl) care, author Harvey Ussery and guest-writers describe everything from anatomy and species selection to feeding, breeding, and selling poultry in the local market.
Environmental Debate: Are Genetically Modified Crops Good for the United States and the Environment?
Issues and Background
Sixty years after Watson and Crick detailed the structure of DNA, 70% or more of U.S. agricultural acreage in 2013 given to soybeans, cotton and corn is growing genetically modified (GM) forms of these crops. More than 70% of corn is transgenic, carrying bacterial DNA that enables the plant’s cells to produce an insecticidal protein—this variety is called BT corn. A similar amount of corn has been genetically modified to withstand a herbicidal chemical known as glyphosate. When a farmer sprays their fields, their HT corn survives as unwanted weeds die.
The best known—but not only—developer of GM crops is the Monsanto Company and, as one might expect, they readily extol the virtues of their products. Claimed benefits include increased farm income, increased crop production, decreased pesticide use and decreased emission of greenhouse gases. Are there data to support such claims?
Just considering corn production, there has indeed been an increase over the period 1996—when GM corn first entered the market—to 2007, but the data suggest that, on a global scale, this increase is a modest 2% (it must be said that some specific regions enjoyed much higher yield increases). Of course, even a modest increase likely will be beneficial with a global human population predicted to reach 9.6 billion in 2050. And again for corn, it is estimated that global pesticide use has declined by 92 million kg (about 20%) since 1996.
Are there any negatives associated with GM crops and the foods produced from them? While it is possible that novel proteins in foods could cause allergic reactions, there is no evidence of such reactions that can be definitively attributed to a GM source. In 2012, it was reported that rats fed HT corn suffered an increased incidence of cancer. Although it caused an understandable stir, this study was criticized on technical grounds and, in the spirit of good science, it needs to be carefully repeated and extended to see if this disturbing result can be replicated.
Another concern is that the long-term use of GM crops may harm the environment. There is already evidence that weeds are evolving resistance to herbicides in areas that grow HT crops, and that insects are evolving resistance to the toxin in BT crops. The evolution of such resistance in pest species is almost inevitable, but is not unique to agricultural systems using GM crops.
Might GM plants harm wildlife? In 1999, it was reported that larvae of the monarch butterfly showed increased mortality when fed pollen from BT corn plants. In nature, larvae feed on milkweed plants that grow as weeds in and around cornfields, and so might be exposed to corn pollen. This effect was strongest for a variety of BT corn not very popular with farmers and which was taken out of use. However, a 2012 study
reported an indirect link between HT corn and declining populations of monarchs. Because HT corn resists herbicide, increased spraying of milkweed has shrunk the butterfly breeding habitat, perhaps by as much as 20% in the eastern U.S.
Americans are relatively sanguine concerning GM crops and foods made from them. For example, although they fill our supermarkets, there’s no legal requirement that such foods be labeled as such. And people don’t seem too concerned—public disinterest likely contributed to the failure of a recent referendum on the topic of labeling in California to gain sufficient support. Europeans are different, with both farmers and consumers adamant that what they call ‘Frankenfoods’ be outlawed.
The issue of GM crops was brought into the limelight in 2013 when a field of GM wheat was found in Oregon. While such wheat had earlier been grown experimentally, it hadn’t been approved for commercial use. The fallout began almost immediately, with Japan and South Korea cutting U.S wheat imports. U.S. farmers then began legal action for loss of earnings against Monsanto Company, the developer of the wheat variety.
GM crops have been in cultivation in the U.S. for nearly 20 years, and debate—and at times rancorous argument—over their use continues. As with any technology, there are potential pros and cons to the growing of such crops and the production of food from them. Whether any changes to public policy may emerge from the GM wheat episode in Oregon remains to be seen, but we must hope that, if changes are made, they will result from considerations of the best scientific evidence available.
Primary Resources and Data
Produced by an independent consultancy that tracks both global and regional data on the cultivation of GM crops and impacts on yields, farm incomes, pesticide use and production of greenhouse gases. Its data are widely cited by Monsanto Company as evidence that GM crops are beneficial.
Seralini, G.-E. et al. 2012. Long Term Toxicity of a Roundup Herbicide and a Roundup- Tolerant Genetically Modified Maize. Food and Chemical Toxicology 50: 4221-4231. Reports increased cancer, kidney disease and mortality in rats fed GM corn. It has been criticized on technical grounds and is a study that sorely needs to be repeated to see if its results can be replicated.
Brower, L.P. et al. 2012. Decline of Monarch Butterfly Overwintering in Mexico: Is the Migratory Phenomenon at Risk? Insect Conservation and Diversity 5: 95-100.Provides evidence that populations of monarch butterflies are declining due to changing weather patterns, forest loss in Mexico and loss of milkweed habitat in the U.S.
The Search for Monsanto’s Rogue GMO Wheat
Brookes, G. and Barfoot, P. 2009. Global Impact of Biotech Crops: Income and
Production Effects 1996-2007. Agbioforum 12: 184-208.
http://www.businessweek.com/articles/2013906920/the9search9for9monsantos9 rogue9gmo9wheatProvides an account of the consequences of the discovery of an unauthorized field of GM wheat in eastern Oregon.
Different Perspectives in the Debate
Do GM Crops Increase Yield?
Monsanto Company’s website paints a rosy picture of the benefits that GM crops provide, but is light on data.
Ferber, D. 1999. GM Crops in the Cross Hairs. Science 286: 1662-1666.
Relevant today although more than 10 years old, this paper objectively discusses evidence on the pros and cons of GM crops and their products.