Climate change on a massive scale is a done deal. Society should focus on adapting to it.
Opening: For
F.O.1 In a major milestone for the collective acknowledgement of impending disaster, nations around the world gathered at COP21 in Paris and agreed that “climate change represents an urgent and potentially irreversible threat to human societies and the planet and thus requires the widest possible cooperation by all countries.” Two primary goals were identified at the conference: 1. limit the increase in the global average temperature to “well below 2°C above pre-industrial levels” (which is approximately 3.6°F) and 2. increase the capacity of the world at large to “adapt to the adverse impacts of climate change.” The agreement called for “ambitious and early action, including major reductions in the cost of future mitigation and adaptation efforts.”
F.O. 2 The prevailing mood in 2015 was one of hope that, if all nations committed to carrying out their pledges, we would be able to take on the climate crisis. But the later decision of President Donald Trump to pull the US out of the Paris Agreement dealt major blows to the global effort. The current US administration, with its petroleum-friendly policies and science-skeptical messaging, has done irreparable damage to the hard-won consensus of COP21.
F.O. 3 Still, the world must move forward. Challenges for the future, as recognized at COP24 in Katowice, Poland, will revolve around “a detailed set of rules and guidelines” for addressing global warming. The question on the minds of world leaders, and for all of us, will be: how exactly should nations proceed over the next several decades, in order to avoid the worst effects of climate change?
F.O. 4 Strategies to combat climate change generally follow one of two approaches: mitigation, to try to limit the rise in global average temperature by reducing the amount of greenhouse gas in the air, and adaptation, to improve the ability of society to adjust to a changing climate. Both of these approaches are critically important and necessary to see us through the coming crisis. I argue that the main thrust of government policy should be on adaptation to climate change, with mitigation strategies taking second priority.
The response to climate change is too slow to meet COP21 targets
F.O.5 One of the central points made during COP21 was that, while the target 2°C increase in global average temperature was a valuable starting point, limiting the rise to 1.5°C would ultimately be necessary to avoid the worst consequences. (Currently, the planet is about 1°C warmer on average than it was during pre-industrial times, prior to the Industrial Revolution in the 1800s.) This is important because, according to the IPCC Special Report released in October 2018, the rise in average temperature is highly likely to “reach 1.5°C between 2030 and 2052 if it continues to increase at the current rate.” While greenhouse gases already in the air today will continue to cause gradual warming for centuries to come, the IPCC report concluded that “these emissions alone are unlikely to cause global warming of 1.5°C.” That means nations around the world have a timeframe of 12 to 34 years to make monumental changes in their governance and infrastructure.
F.O.6 This emergency has not sprung upon the world suddenly — it has, of course, been a growing concern for many years. Although suspicions were brewing in the scientific community for at least half a century, the 2006 documentary “An Inconvenient Truth” featuring Al Gore may be considered the watershed that raised the issue to the forefront of public consciousness. Fast forward 12 years, and the current administration is rolling back regulations that limit greenhouse gas emissions from vehicles and power plants.
F.O.7 Contrast this situation with the response of the US and the rest of the world to discovery of the Antarctic ozone hole in 1985. The international Montreal Protocol in 1987, followed by amendments and additional protocols throughout the 1990s, brought nations together to ban emissions of ozone-depleting chlorofluorocarbons. , This remarkable accomplishment proved that it is possible for countries to collaborate with the common goal of averting environmental catastrophe. Yet it also demonstrates that climate change is a very different beast — and it will be a matter of generations, not decades, before the world gets a handle on it.
Mitigation strategies take a long time to be developed and adopted
F.O.8 Enormous scientific strides are being made to develop carbon-neutral energy alternatives as well as cost-effective technologies for carbon capture. These advances are the key to solving the climate crisis in the long term. However, spectators outside the field tend to grossly underestimate the time and investment needed to adopt these innovations on a global scale. Each of the hundreds-to-thousands of technologies that have been demonstrated at lab or pilot scale must be scaled up to meet the demands on at least a regional scale, with each region around the world requiring a unique approach. It will require extensive collaboration between local communities, private companies, utilities, and the government.
F.O.9 We are unlikely to see this task come close to fruition within the next 34 years, even if we discover a scientific “miracle cure” that drastically alters the way we produce power — typical estimates are more in the range of a hundred years or more. Even the Internet, a revolutionary yet singular technology, took about 3 decades after its initial invention to become fully integrated in global society.
Adaptation strategies are practical, achievable, and politically uncontroversial
F.O.10 While climate change is a polarizing subject in the political sphere, effective adaptation to it can be framed in a manner that appeals to both sides. Most everyone agrees that managing water shortages, relocating refugees due to natural disasters, and improving buildings and infrastructure to better withstand the elements are issues that should be addressed by government policy. In the aftermath of Hurricane Katrina in 2005, there was a massive, largely nonpartisan public outcry about the failure of the Bush administration to provide sufficient aid to the victims and to repair destroyed buildings and roads in New Orleans.
F.O.11 Goals associated with climate change adaptation are usually concrete and tangible, with clear positive outcomes. The upgrading of structural materials in climate-sensitive areas can be streamlined into construction projects with relative ease. A complementary approach would be to implement more sophisticated evacuation protocols and disaster-relief policies in these areas. Precedents already exist in many countries that have historically been more vulnerable to natural disasters. Such tasks are far more feasible in the immediate term than the gargantuan feat of reducing greenhouse gases, the sources of which remain poorly understood and immensely difficult to control.
F.O.12 The fact that these efforts should be achievable on regional to local scales and on a time scale of years to decades means that we can also adapt our adaptation efforts in response to gradual climate shifts. In this way societies around the world can endure, and even thrive, through the time it will take to develop and integrate carbon-neutral technologies.
Opening: Against
A.O.1 Climate change is happening, accelerating, and causing widespread harm to societies, economies, and the environment. More severe effects are predicted for the future. The present debate, therefore, addresses unanswered questions about climate change: 1. To what extent can the human enterprise adapt to a radically warmer planet and all the attendant hazards? 2. Can the worst effects be mitigated, within reasonable bounds of timing, feasibility, and cost, and if so, how? This essay is an attempt to answer the second question, and therefore to present the case that mitigation is not only an option, but by far the best choice for the planet’s future: “Reaching and sustaining net zero global anthropogenic CO2 emissions . . . would halt anthropogenic global warming . . .”
A.O.2 The current climate change phenomenon is caused by increasing concentrations of greenhouse gasses (GHG) in the Earth’s atmosphere. The GHG (principally carbon dioxide, but also methane, nitrous oxide, and other trace gasses), trap infrared radiation (heat) in the lower atmosphere. The increased heat not only raises temperatures, but also causes a cascade of direct and indirect effects, including stronger storms, longer and more intensive droughts, and more frequent and intensive flooding in others.2 Sea levels are rising because the oceans expand as the water warms, and because the rising temperatures cause melting of glaciers and ice sheets. As ice cover decreases in the Arctic and Antarctic, the reflectivity (albedo) of the Earth’s surface decreases, meaning the land and water absorb more heat. It is also likely that warming of vast regions of tundra in boreal and arctic zones will release significantly large amounts of GHG that have long been sequestered in tundra soils and permafrost. The oceans are becoming more acidic as they absorb excess amounts of carbon dioxide. Climate change disrupts ecosystems as species adapt in various ways to rising temperatures and changes in other habitat conditions. Some individuals and species, failing to adapt, will perish.
A.O.3 Mitigation does not mean a total reversal of warming, about 1.5°C of which has already been locked in as the result of past emissions. Rather, mitigation, as defined here, would be the result of a suite of actions that would prevent the most catastrophic effects of climate change, by limiting the increase in global average temperature to 2°C or less over the pre-industrial baseline, the policy commitment of the 2016 Paris Climate Agreement. The most recent estimate indicate that net zero GHG emissions will need to be attained by 2050 to avoid going beyond a 1.5°C increase in global average temperature.
A.O.4 There are three main avenues for mitigation: 1. reducing emissions of GHG; 2. carbon capture and sequestration (CCS); and 3. solar radiation management (SRM). Other classifications are possible, e.g., CCS and SRM are sometimes lumped together as climate geoengineering, and CCS can be subdivided into biological and technological (or green and gray) approaches. Feasibility, cost, effectiveness, and risks of unintended consequences need to be considered. The literature is vast; Hawken outlines 98 separate mitigation methods, so the following treatment is a greatly abbreviated summary.
Reducing GHG emissions
A.O.5 The primary sources of anthropogenic GHG emissions are, in order of magnitude: fossil-fuel based energy production and transportation; land use, agriculture and forestry; and industrial, commercial, and residential sources. Switching energy production and transportation systems to non-carbon sources (such as solar, wind, nuclear, renewable electric, and hydrogen power), would reduce global carbon dioxide emissions by 50–60% (estimated from Hannah and Roser). Although this shift has begun, it is not sufficient either in magnitude or speed to achieve the needed reductions. Even in the unlikely case that all anthropogenic GHG sources were to reach zero emissions within the next decade or two, warming would be slowed only enough to prevent more than 2°C warming, but not enough to attain the 1.5°C threshold. Mitigation cannot succeed solely by emission controls.
Carbon capture and sequestration
A.O.6 Carbon dioxide is taken up and stored by photosynthetic organisms (green plants and algae). The more plant and algal biomass that is produced, the more carbon is sequestered. Although this storage is not permanent, it provides the opportunity to reach a more optimal global equilibrium between green biomass and the atmosphere, with the effect of reducing net carbon emissions. Reforestation, afforestation, and protection of existing forests could make major contributions to GHG reductions, but must be balanced against other land use needs, especially agriculture. Marshes, seagrasses, and coral reefs sequester large amounts of carbon dioxide, but currently are threatened by sea level rise, coastal development, and in the case of coral reefs, warming and acidification of the oceans. Protection and enhancement of these green resources is less costly than most other mitigation methods, making a substantial contribution to CCS, while contributing to a healthy environment. Crops grown in large quantities for energy production (e.g., second-generation biofuels), for other commercial uses (e.g., hemp), or specifically for CCS can also contribute, but may compete with food production and other essential land uses.
A.O.7 A variety of methods can be used to capture carbon dioxide from emission sources, or directly from the atmosphere. Once captured, the carbon dioxide may be pumped into deep underground reservoirs for long-term sequestration or sold for other uses. Although there has been some research into and limited demonstrations of these technologies, little has been published about them.
Solar radiation management
A.O.8 Global warming could be mitigated through blocking solar radiation before it reaches the Earth’s surface, collectively known as SRM. An article by Ming et al. is a comprehensive review of the possibilities for SRM, and compares SRM to “Earth radiation management,” a suite of technological methods to increase radiation from the Earth to space.
A.O.9 The most widely discussed method of SRM is global-scale deployment of sulfate aerosols, or other absorbing substances, in the atmosphere. This technique mimics the effects of large volcanic eruptions; known to cool the climate over short periods (~1 year). Thus, deployment would have to be continuous until GHG emissions are sufficiently reduced. Although modeling has shown this method is cost-effective, there is concern, as with all SRM, over side effects, including stratospheric ozone depletion, acid rain, changes in regional precipitation, and human health risks.
Mitigation can be an effective approach to climate change
A.O.10 The recent IPCC report makes it clear that mitigation measures, if fully employed within the next decade or two, will limit global warming to 2°C or less, thereby avoiding the most catastrophic effects of unchecked climate change. Net carbon emissions will have to drop to zero or below. This level can be attained by massive reductions in fossil fuel combustion coupled with aggressive investments in broad-based CCS. With a strong emphasis on green CCS, it will be unnecessary to invest heavily in questionable technologies such as CCS at fossil-fueled energy production facilities, or SRM. The movement toward a carbon-neutral society is already underway and gathering momentum. Commitments by public and private entities have been made, from international to local, to effect changes. This momentum must increase exponentially over the next decade.
A.O.11 To accept warming of 5°C or more over the next century will have catastrophic consequences for the world’s people, economies, and the environment, regardless of what adaptation measures are taken.
Rebuttal: For
F.R.1 The main thrust of the opponent’s opening statement is that the goal of limiting the global average temperature increase to 2°C or less by 2050 can be achieved by mitigation strategies focusing on carbon capture and sequestration (CCS) (A.O.3 and 04), specifically the production of additional biomass and the protection of forests, marshlands, and reefs which draw down carbon dioxide from the atmosphere.
Growing new crops for carbon dioxide sequestration
F.R.2 A key difficulty in repurposing land for CCS lies in the competition with land used for agriculture. Half of all habitable land is used for food production, and although agricultural technology and genetic engineering have improved agricultural efficiency over the last fifty years, land area still plays a major role in determining yield in most developing countries. Any CCS program involving substantial use of land for new crops cannot compete with land used for agriculture in those countries, unless technological advancements are made which will likely take a number of years to implement, more time than we have left for combating climate change.
F.R.3 In North America and Europe, higher agricultural yields for food production mean that more land can be spared, but that land is being used increasingly to produce biofuels. According to some assessments, the processing and combustion of biofuels generates nearly 3 times more carbon dioxide than is sequestered from the atmosphere, so these crops cannot be considered truly carbon neutral. Unexpected effects of land use changes for biofuels or other crops can also cause more greenhouse gas emissions, such as the increase in nitrous oxide from fertilizers.
F.R.4 On a political note, the U.S. EPA Renewable Fuel Standard requires a percentage of biofuel to be blended into petroleum-based transportation fuels. Growing new crops for CCS purposes will compete with either food or energy production, leading to opposition from both farm coalitions and oil companies, arguably the two most powerful forces in government, at least in the United States.
Protection and enhancement of natural carbon dioxide sinks
F.R.5 Preserving existing land for CCS faces challenges in developing countries where the demand for agricultural land and natural resources is growing. For example, the deforestation of the Amazon rainforest has been a major problem for decades. The large landmass of the forest is an important sink for greenhouse gases, and its encroachment by agricultural and logging interests is a significant cause of global warming.
F.R.6 In 2008, delegates to the Convention for Biological Diversity pledged to eliminate deforestation by 2020. While the rate of deforestation has decreased since the 1990s, illegal rainforest destruction remains a serious issue with nearly 8,000 square kilometers destroyed in 2018. When the natural environment is jeopardized by economic expansion, even a united political will may not be sufficient to prevent its devastation.
F.R.7 The opponent argues that protecting carbon dioxide sinks in the natural environment such as marshlands and coral reefs will mitigate global warming (A.O.6). It is definitely important to conserve these vulnerable ecosystems, but it is unlikely to contribute significantly to CCS.
F.R.8 The effort required to maintain these resources is considerable given the many factors that threaten their survival. Not only do human activities upset the delicate balance of life in these ecosystems, but the climate shifts induced by global warming cause damage that they may not be able to recover from. The hurricanes Maria and Irma that ravaged the Caribbean in 2017 disrupted many coral reef colonies, and scientists predict that the increasing frequency of such natural disasters will deteriorate their health.
F.R.9 Since the details of climate change are not well understood, it is not clear how coral reefs and other resources can be shielded from its consequences. Even if it is possible to protect these regions, utilizing them for CCS is a complex task. In the case of coral reefs, carbon dioxide is converted into calcium carbonate, which has the side effect of worsening ocean acidification. Land-based ecosystems such as forests have no known negative feedback effects, but would need to rapidly increase their land area before 2050. It takes a hundred years or more for destroyed rainforest to grow back. This is not fast enough to attain the level of CCS needed to limit the global average temperature and avoid climate change on a massive scale.
Rebuttal: Against
Policies and trends
A.R.1 The “for” statement begins by citing the goals and conclusions of the Paris Climate Agreement, which outline a balanced, combined strategy of mitigation and adaptation. It is then argued that “. . . the later decision of President Donald Trump to pull the US out of the Paris Agreement dealt major blows to the global effort.” (F.O.2). Given that there is a growing consensus among governmental, commercial, and non-governmental sectors that massive mitigation efforts are essential, the Trump declaration, although certainly not a positive development, seems more symbolic than potent. It is not at all clear that it “. . .has done irreparable damage to the hard-won consensus of COP21.” (F.O.2)
A.R.2 The principal argument given for prioritizing adaptation over mitigation is that the necessary degree of mitigation cannot be achieved within the “timeframe of 12 to 34 years.” (F.O.5). Although the challenge is indeed “monumental” (F.O.5), no solid evidence is presented that it will be impossible. Yes, the current US government has engaged in a spate of anti-mitigation policy changes, but changes in policy do not necessarily mean changes in practice. Will the US really invest in more coal-fired power plants? The trend is toward disinvestment in fossil fuel power and investment in renewable energy, regardless of national policies. Globally, nationally, and regionally, economic and social forces will continue to accelerate this trend. There is, in fact, evidence that net zero carbon emissions can be achieved within the next 2–3 decades.
A.R.3 The “for” statement does not provide support for the claim that “. . . climate change is a very different beast” from the chlorofluorocarbon (CFC) case (F.O.7). If they are so different, why make the analogy? It is true that the GHG problem is larger in scope and more diffuse than the CFC problem, but is this not a matter of degree rather than taxonomy?
Timely mitigation is possible
A.R.4 No evidence is supplied to support the statements in F.O.8: “Mitigation strategies take a long time to be developed and adopted.” In fact, the technologies required to mitigate climate change over the next few decades are well- or fully-developed, including renewable power generation, electrification of transportation systems, and green CCS (we know very well how to grow trees, for example). The challenge will be deployment of already proven systems at the necessary scales. The “. . . technologies that have been demonstrated at lab or pilot scale . . .” (F.O.8) are the gray CCS technologies, which would capture GHG from emission sources or directly from the atmosphere. In A.O.10, it is shown that these methods will not be essential to mitigation: “. . . mitigation measures, if fully employed within the next decade or two, will limit global warming to 2°C or less.” No “miracle cure” (F.O.9) will be required.
A.R.5 Indeed, climate change has been a “. . . polarizing subject in the political sphere.” (F.O.10), but how much longer will it remain so? The real manifestations of climate change in recent years have been making it apparent — to all but the most intransigent deniers — that it cannot be wished away or quashed by unbelief.
Adaptation is not enough
A.R.6 The main defense of adaptation in the “for” statement is introduced by the phrase “Most everyone agrees . . .” (F.O.10), which is a very weak assertion at best. Although it may be true that there is strong support for some adaptation measures, how do we know that “most everyone agrees?” To take one example, relocating refugees, whether from natural disasters or other effects of climate change, will be a huge challenge logistically, economically, and politically. The Katrina example given in F.O.10 (“In the aftermath of Hurricane Katrina in 2005, there was a massive, largely nonpartisan public outcry about the failure of the Bush administration to provide sufficient aid to the victims and to repair destroyed buildings and roads in New Orleans”) involved a few thousand refugees; climate change refugees will number in the tens of millions. Where will they go? Who will want them? Consider the current refugee conflicts in Africa, Europe, and North America. As another example, there is no feasible scale of infrastructure development that can protect all the residents of coastal areas and low islands around the world from sea level rise.
A.R.7 Strategic and orderly development of adaptation policies and their implementation will be essential, but not sufficient, responses to climate change in the near term. The scenarios outlined in the “for” statement, however, cannot be accomplished at the scale or in the time frame to prevent catastrophic consequences, unless combined with massive mitigation efforts. It is not even clear what the following statement means: “The upgrading of structural materials in climate-sensitive areas can be streamlined into construction projects with relative ease.” (F.O.11). If the statement is a reference to infrastructure improvements such as seawalls, only a tiny fraction of climate-sensitive areas could be protected, logistically or economically. Finally, improving evacuation protocols and disaster relief efforts are important, but hardly strategic approaches to the climate change problem: “A complementary approach would be to implement more sophisticated evacuation protocols and disaster-relief policies in these areas” (F.O.11).
Closing: For
F.C.1 The opponent provides no supporting evidence for a number of key claims in the rebuttal. While renewable energy investment has increased in recent years, as noted by the opponent in A.R.2, no examples are raised to suggest that these investments are of a sufficient magnitude to meet the mitigation targets of COP21. The assertion that “there is, in fact, evidence that net zero carbon emissions can be achieved within the next 2–3 decades” (A.R.2) is also unsubstantiated.
F.C.2 To the contrary, a combined climate and energy analysis concluded in 2003 that at least 900 megawatts of carbon-free energy must be added to the global energy system daily for 50 years in order to limit warming to 2°C. Over fifteen years later, only one-sixth of that amount is being added (about 150 megawatts daily), such that 400 years will be required to achieve a similar transformation. No amount of rapid acceleration in investment is going to change that reality before 2050.
F.C.3 Adaptation, on the other hand, encompasses a variety of approaches that can be taken now on a grand scale without relying on future projections of technology development. As the opponent states in A.R.6, climate change refugees will grow in numbers as natural disasters become more frequent and severe. Yet adaptation can also come in the form of aid delivered to climate-sensitive regions including coastal areas, which can alleviate the worst effects and avoid or delay the need for relocation.
F.C.4 If nations around the world take measures to prepare for and respond to catastrophic events, the inevitability of global warming can be endured. Climate change will be experienced most acutely by those living in the poorest countries, who are least able to protect themselves. The position of developed nations, which will remain relatively unscathed, should be to accept that carbon neutrality is a long-term solution, and fight to defend the vulnerable from climate devastation.
Closing: Against
A.C.1 The chief argument for rapid and comprehensive efforts to mitigate climate change is that society and the environment will not be able to adapt without massive disruptions and harm. Human health, nutrition and well-being, the global economy, and aquatic and terrestrial ecosystems are all at risk. Some damage has already happened, and more is unavoidable, but through mitigation society can avert the worst consequences of rising temperatures, rising seas, and the attendant failures of infrastructure, agriculture, and ecosystems.
A.C.2 Effective mitigation will not require huge investments in risky or unproven technologies such as SRM, or huge CCS infrastructure projects. A combination of greatly reduced GHG emissions plus intensive employment of green CCS can achieve the <2°C goal within the next two decades. The technical and economic barriers can be overcome, but only with a global consensus coupled with political commitment and prompt action.
A.C.3 The principal means of adaptation are infrastructure improvements and relocation of human populations. Of the multiple climate-related causes for human migration, consider sea level rise. In some areas, mainly large coastal cities, massive infrastructure projects will be appropriate adaptation measures. Nevertheless, sea levels that are likely within this century will inundate large areas regardless of what barriers can be constructed. On its face, the retreat-relocate adaptation strategy is conceptually simple. Without mitigation, however, the disruption will be immense, both for those relocating and for the recipient communities. It has been shown that depopulation of coastal areas is not quick, cheap, or politically popular. With tens of millions of potential climate refugees, the outcome of failing to prioritize mitigation could be a global dystopia.
A.C.4 Both mitigation and adaptation are essential responses to climate change. This debate is about when, where, and how rather than whether we should employ these tools. For mitigation, the answers are now, everywhere, and using proven methods.
Debaters
For
Dr. Mica C. Smith is a postdoctoral research associate in chemical engineering at MIT. She earned her PhD from University of California, Berkeley. Her research has included analyzing basic properties of greenhouse gases and developing materials and methods to reduce harmful emissions from fuels. She can be found on Twitter. Dr. Smith’s academic page can be found here and research can be found here.
Against
Dr. Stephen J. Jordan is an environmental scientist who retired from the U.S. Environmental Protection Agency (EPA) at the end of 2015. Before retirement, he was Assistant Director of the National Health and Environmental Effects Laboratory in EPA’s Office of Research and Development. Previous employment included the Maryland Department of Natural Resources, The U.S. Army Corps of Engineers, and Johns Hopkins University.
Dr. Jordan’s prior research, relevant to this written debate include: Governance and the Gulf of Mexico Coast: How Are Current Policies Contributing to Sustainability? and Sustainability — What Are the Odds? Envisioning the Future of Our Environment, Economy and Society
