Definitions: Adaptation, Mitigation, and Stabilization
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The IPCC's 4th Assessment Report emphasizes the importance of both mitigation and adaptation strategies in order to deal with the challenges of climate change. Mitigation strategies are necessary to slow and eventually halt and reverse the accumulation of greenhouse gases (GHGs). Possible mitigation strategies include the direct reduction of GHG emissions, providing economic and technological resources necessary for others (e.g., poor nations) to reduce emissions, and preserving “carbon sinks” (e.g., rainforests) that absorb GHGs that otherwise would accumulate in the atmosphere. Adaptation strategies, by contrast, involve the modification of human behavior or the environment in order to avoid the harmful consequences produced by climate change.
While strategies designed to mitigate extent of climate change by reducing the rate, and ultimately limiting and reversing the concentration of greenhouse gasses (GHGs) are crucially important, mitigation alone is not enough. Current concentrations are already causing damaging environmental changes. Even with a substantial reduction in the rate of emissions the stocks of GHGs will continue to rise faster than they are dispelled. Human communities will have to take steps to adapt to dangerous climate change that all of our mitigation efforts will not be sufficient to prevent. The IPCC offers the following definitions pertaining to the problem of adaptation:
For more detail, see: Working Group 2 (AR4) Summary for Policy Makers: Impacts, Adaptation, and Vulnerability
While strategies designed to mitigate extent of climate change by reducing the rate, and ultimately limiting and reversing the concentration of greenhouse gasses (GHGs) are crucially important, mitigation alone is not enough. Current concentrations are already causing damaging environmental changes. Even with a substantial reduction in the rate of emissions the stocks of GHGs will continue to rise faster than they are dispelled. Human communities will have to take steps to adapt to dangerous climate change that all of our mitigation efforts will not be sufficient to prevent. The IPCC offers the following definitions pertaining to the problem of adaptation:
- Adaptive capacity is the ability of a system to adjust to climate change (including climate variability and extremes) to moderate potential damages, to take advantage of opportunities, or to cope with the consequences.
- Vulnerability is the degree to which a system is susceptible to, and unable to cope with, adverse effects of climate change,including climate variability and extremes. Vulnerability is a function of the character, magnitude, and rate of climate changeand variation to which a system is exposed, its sensitivity, and its adaptive capacity.
For more detail, see: Working Group 2 (AR4) Summary for Policy Makers: Impacts, Adaptation, and Vulnerability
The Promise of Technological Innovation: The "Valley of Death" Problem
For those who are by nature technological optimists, there is the hope that rapid breakthroughs in energy efficient technologies, and more importantly, renewal, clean fuels, and robust systems that allow for storage and transmission of energy without significant loss can set humanity on a quick path toward stabilizing GHG emissions. But hard-nosed scientists and equally cautious economists tend to note two worries.
One worry is that thus far, there has been no Moore's Law in energy technology. Moore's Law is the crystallization of the trend toward doubling of microprocessor speed and data capacities roughly every three years.
The second worry is the economic companion to the lack of comparable technological advances. The Valley of Death, as it is known, points to the range of impediments to feasible financing of research and development in the energy sector. Investors have to march through the economically treacherous valley of death spanning the distance between technology creation and its dissemination in economically profitable ways. One element is simply the risk factor, given the lack of a Moore's Law that leads one to greater optimism about new technological breakthroughs. Another factor is the existence of "incumbent technologies" or fuels that dominate the market, fit well with existing technologies such as automobiles and other modes of transportation that run on fossil fuels, and quite often, enjoy current state subsidies or operate facilities paid for in part by subsidies from an earlier generation. Thus many experts expect that the nearest-term opportunities for mitigation will come from efficiency gains in the use of traditional sources of energy rather than the development of comparably priced, scalable replacement sources. (See the McKinsey "cost of abatement" curves below)
A 2011 report, Bridging the Clean Energy Valleys of Death, from the Breakthrough Institute Energy and Climate Program, "documents the challenges facing American energy entrepreneurs seeking to commercialize advanced energy technologies to enhance US energy, economic, and environmental security."
One worry is that thus far, there has been no Moore's Law in energy technology. Moore's Law is the crystallization of the trend toward doubling of microprocessor speed and data capacities roughly every three years.
The second worry is the economic companion to the lack of comparable technological advances. The Valley of Death, as it is known, points to the range of impediments to feasible financing of research and development in the energy sector. Investors have to march through the economically treacherous valley of death spanning the distance between technology creation and its dissemination in economically profitable ways. One element is simply the risk factor, given the lack of a Moore's Law that leads one to greater optimism about new technological breakthroughs. Another factor is the existence of "incumbent technologies" or fuels that dominate the market, fit well with existing technologies such as automobiles and other modes of transportation that run on fossil fuels, and quite often, enjoy current state subsidies or operate facilities paid for in part by subsidies from an earlier generation. Thus many experts expect that the nearest-term opportunities for mitigation will come from efficiency gains in the use of traditional sources of energy rather than the development of comparably priced, scalable replacement sources. (See the McKinsey "cost of abatement" curves below)
A 2011 report, Bridging the Clean Energy Valleys of Death, from the Breakthrough Institute Energy and Climate Program, "documents the challenges facing American energy entrepreneurs seeking to commercialize advanced energy technologies to enhance US energy, economic, and environmental security."
Measuring the Cumulative GHG Emissions of Nations
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One common approach to questions about duties to mitigate the accumulation of GHGs in the atmosphere begins with some reflection on the cumulative contribution that a nation or region of the world has made to the current stock. There is, of course, much debate about whether and how past emissions ought to figure in any judgment of the proportion of current emissions any given country should be allocated, the historical accumulation estimates are difficult to ignore entirely.
What we know is that any attempt to fashion an agreement on duties of mitigation will pit the interests of developed countries against developing nations. So for example, one quarter of the world is estimated to live under conditions of energy poverty. Economic development and improvements in the standard of living is stunted by the lack of electrical power, and until real alternatives to fossil fuel use are developed, that will mean that any comprehensive attempt to reduce and eventually stabilize and reduce the overall accumulation, without condemning a quarter of humanity to remain locked in desperate poverty, will require that the entire world operate under a single annual emissions budget. The distributive question, then, becomes one of how to allocate increasingly scarce emissions rights.
One proposal going forward is that every nation should have equal per capita emissions rights. The merit of such a proposal is that every person, regardless of nationality, is treated equally. But it is an account of equality that rests on a history in which more than half of the total 1 Trillion tons of GHGs - estimated to be the upper limit if the temperature rise is to be kept at around 2 degrees C - has been used already.
Other approaches attempt to answer emissions allocation questions in ways sensitive to the fact that the simple division between affluent nations and poor nations masks the equally morally important fact that not all people in rich nations are poor and not all people in rich nations are rich. For an example of one such proposal, see the Greenhouse Development Rights Framework proposed by Paul Baer et al.
However we factor in past emissions in the way we think about mitigation duties, the World Resources Institute (WRI) offers some notes about the hidden complexity even in the simple process of measuring cumulative emissions. So we know that by some estimates the EU, with 16 percent of current fossil fuel emissions, accounts for nearly 27 percent of cumulative emissions. Although developing countries have been estimated as generating 41 percent of current fossil fuel emissions, they have contributed only 24 percent of cumulative emissions. But the WRI notes that historic contribution can be assessed in different ways, including the following:
While the biggest historical contributors to the accumulated stock of emissions thus far are based in the rich industrial nations, the composition of the biggest historical emitters will change as the threshold of dangerous climate change is approached. One widely respected projection estimates that by 2050 the percentage of total emissions since 1970 attributable to the thirty economically most developed nations will be surpassed by the cumulative emissions generated during that period from within the BRIC nations – Brazil, Russia, India, and China – and the share attributable to the rest of the world is projected to lag only slightly behind the combined total for the thirty most developed nations (OECD 2008). Whatever the precise proportions turn out to be in 2050, the clear trend is one in which the historical emissions attributable to developing or less developed nations is catching up to the historical emissions attributable to developed nations.
Source: Organization for Economic Cooperation and Development (OECD). (2008) OECD Environmental Outlook to 2030, Paris: OECD Publishing.
What we know is that any attempt to fashion an agreement on duties of mitigation will pit the interests of developed countries against developing nations. So for example, one quarter of the world is estimated to live under conditions of energy poverty. Economic development and improvements in the standard of living is stunted by the lack of electrical power, and until real alternatives to fossil fuel use are developed, that will mean that any comprehensive attempt to reduce and eventually stabilize and reduce the overall accumulation, without condemning a quarter of humanity to remain locked in desperate poverty, will require that the entire world operate under a single annual emissions budget. The distributive question, then, becomes one of how to allocate increasingly scarce emissions rights.
One proposal going forward is that every nation should have equal per capita emissions rights. The merit of such a proposal is that every person, regardless of nationality, is treated equally. But it is an account of equality that rests on a history in which more than half of the total 1 Trillion tons of GHGs - estimated to be the upper limit if the temperature rise is to be kept at around 2 degrees C - has been used already.
Other approaches attempt to answer emissions allocation questions in ways sensitive to the fact that the simple division between affluent nations and poor nations masks the equally morally important fact that not all people in rich nations are poor and not all people in rich nations are rich. For an example of one such proposal, see the Greenhouse Development Rights Framework proposed by Paul Baer et al.
However we factor in past emissions in the way we think about mitigation duties, the World Resources Institute (WRI) offers some notes about the hidden complexity even in the simple process of measuring cumulative emissions. So we know that by some estimates the EU, with 16 percent of current fossil fuel emissions, accounts for nearly 27 percent of cumulative emissions. Although developing countries have been estimated as generating 41 percent of current fossil fuel emissions, they have contributed only 24 percent of cumulative emissions. But the WRI notes that historic contribution can be assessed in different ways, including the following:
- "The cumulative emissions approach weighs all historic emissions equally, regardless of when they occurred. A ton of CO2 emitted in 1850 has the same “value” as a ton of CO2 emitted in 2005.
- An alternative approach assesses a country’s contribution to increased atmospheric CO2 concentrations. By taking into account the decay of GHGs over time, this approach estimates a country’s share of emissions presently in the atmosphere.
- A third approach attempts to measure a country’s contribution to the increase in global average temperature (approximately 0.6° C, globally, above pre-industrial levels)."
While the biggest historical contributors to the accumulated stock of emissions thus far are based in the rich industrial nations, the composition of the biggest historical emitters will change as the threshold of dangerous climate change is approached. One widely respected projection estimates that by 2050 the percentage of total emissions since 1970 attributable to the thirty economically most developed nations will be surpassed by the cumulative emissions generated during that period from within the BRIC nations – Brazil, Russia, India, and China – and the share attributable to the rest of the world is projected to lag only slightly behind the combined total for the thirty most developed nations (OECD 2008). Whatever the precise proportions turn out to be in 2050, the clear trend is one in which the historical emissions attributable to developing or less developed nations is catching up to the historical emissions attributable to developed nations.
Source: Organization for Economic Cooperation and Development (OECD). (2008) OECD Environmental Outlook to 2030, Paris: OECD Publishing.
Altering the Built Environment: The Structure of Buildings and the Siting of Infrastructure
We often think of design changes in buildings as a useful way of mitigating GHG emissions by reducing the need for fossil fuels required for heating and cooling. In addition, such changes are part of an overall adaptation strategy as well insofar as re-engineering old buildings and designing new ones to accomodate local rises in temperature also make it possible to better withstand severe weather events. A 2005 report produced for the Pew Center on Global Climate Change, Towards a Climate-Friendly Built Environment offers a number of suggestions. The Forward of the report begins with the following observation:
"Buildings in the United States—homes, offices, and industrial facilities—account for over 40 percent of our nation's carbon dioxide emissions. Most of these emissions come from the combustion of fossil fuels to provide heating, cooling, and lighting and to run electrical equipment and appliances. The manufacture of building materials and products, and the increased emissions from the transportation generated by urban sprawl, also contribute a significant amount of greenhouse gas (GHG) emissions every year."
Note that there are many ways of carving up the emissions pie, for example, by economic sector, such as agriculture, manufacturing, transportation. The range of sectoral estimates - agriculture's share, for example - can vary widely, depending on how inclusive the life-cycle analysis is. Examples of these variations can be found at Farms, Feedlots, and Forests. But if we look at some functional ways of carving up the emissions pie, we might find that energy use across all economic sectors is cluster in the design and siting of buildings, as this Pew Study indicates. Functional and economic sector estimates, then, offer cross-cutting insights.
"Buildings in the United States—homes, offices, and industrial facilities—account for over 40 percent of our nation's carbon dioxide emissions. Most of these emissions come from the combustion of fossil fuels to provide heating, cooling, and lighting and to run electrical equipment and appliances. The manufacture of building materials and products, and the increased emissions from the transportation generated by urban sprawl, also contribute a significant amount of greenhouse gas (GHG) emissions every year."
Note that there are many ways of carving up the emissions pie, for example, by economic sector, such as agriculture, manufacturing, transportation. The range of sectoral estimates - agriculture's share, for example - can vary widely, depending on how inclusive the life-cycle analysis is. Examples of these variations can be found at Farms, Feedlots, and Forests. But if we look at some functional ways of carving up the emissions pie, we might find that energy use across all economic sectors is cluster in the design and siting of buildings, as this Pew Study indicates. Functional and economic sector estimates, then, offer cross-cutting insights.
The Role of Local Governments in Climate Change Adaptation and Greenhouse Gas Mitigation Efforts
Alterations in the built environment of cities, whether intended for the purpose of furthering global GHG emissions mitigation, local adaptation, or both, has been a priority for many local governments. Some cities have taken prominent steps to make the city more livable and more secure for its citizens in expected scenarios in which higher average temperatures and more severe weather events pose threats to public safety. For example, Chicago has focused on green roofs, blue roofs, and planting more urban trees, for example, both act as carbon sinks that mitigate aggregate emissions build-up, but perhaps more strategically for local interests, reduce the "heat island effects" of large buildings and massive hardscapes that trap heat and pose both immediate human health risks and long-term risks of environmental degradation.
Many of the local governments around the world have made commitments to do their part and joined forces to exchange ideas about what can be achieved at the local level. The most prominent of such organizations is ICLEI - Local Governments for Sustainability, which describes itself as "an association of over 1220 local government Members who are committed to sustainable development. Our Members come from 70 different countries and represent more than 569,885,000 people."
In an Op-Ed in the New York Times, the argument is that in addition to reduction of urban heat island effects, planting trees might matter equally for the sake of other environmental goals, including "cleaning up the most toxic wastes, including explosives, solvents and organic wastes, largely through a dense community of microbes around the tree’s roots that clean water in exchange for nutrients, a process known as phytoremediation."
Many of the local governments around the world have made commitments to do their part and joined forces to exchange ideas about what can be achieved at the local level. The most prominent of such organizations is ICLEI - Local Governments for Sustainability, which describes itself as "an association of over 1220 local government Members who are committed to sustainable development. Our Members come from 70 different countries and represent more than 569,885,000 people."
In an Op-Ed in the New York Times, the argument is that in addition to reduction of urban heat island effects, planting trees might matter equally for the sake of other environmental goals, including "cleaning up the most toxic wastes, including explosives, solvents and organic wastes, largely through a dense community of microbes around the tree’s roots that clean water in exchange for nutrients, a process known as phytoremediation."
Population Growth and The Carbon Footprint of Human Reproduction
The ultimate impact of increased concentration of dangerous GHG accumulation in the atmosphere depends on the prospects for altering, whether by state regulation or motivating voluntary behavioral changes, indeed, involving many of the individual choices that many consider among the most personal and most private. For example, two of the main drivers of global climate change are demographic factors - overall population increase and increase in the population of persons enjoying higher levels of economic development and personal consumption.
One option then would seem to be to establish policies for limiting the growth of the human population, and such policies are fraught with easily imaginable worries. One might immediately assume that such policies are likely to be targeted at some of the world's most disadvantaged groups, including the familiar ethnically defined groups historically subject to the brute end of eugenic policies.
However, any population policy likely to be part of an effective climate mitigation strategy would have to target the reproductive choices of the global rich. For it is the offspring of the global rich who can be expected to consume a disproportionate share of the world's resources in general and disproportionately contribute to the increase in the stocks of GHGs. For example, If you live in the United States, each child you have increases your lifetime carbon legacy by 5.7 times.
Another option, of course, would be to establish policies that change the behavior of citizens of the developed world who consume a vastly disproportionate share of the Earth's resources and in the process, contribute disproportionately to climate change. As the discussion below indicates, the extent of the change that may be required by the world's largest emitters is substantial.
The ultimate impact of increased concentration of dangerous GHG accumulation in the atmosphere depends on the prospects for altering, whether by state regulation or motivating voluntary behavioral changes, indeed, involving many of the individual choices that many consider among the most personal and most private. For example, two of the main drivers of global climate change are demographic factors - overall population increase and increase in the population of persons enjoying higher levels of economic development and personal consumption.
One option then would seem to be to establish policies for limiting the growth of the human population, and such policies are fraught with easily imaginable worries. One might immediately assume that such policies are likely to be targeted at some of the world's most disadvantaged groups, including the familiar ethnically defined groups historically subject to the brute end of eugenic policies.
However, any population policy likely to be part of an effective climate mitigation strategy would have to target the reproductive choices of the global rich. For it is the offspring of the global rich who can be expected to consume a disproportionate share of the world's resources in general and disproportionately contribute to the increase in the stocks of GHGs. For example, If you live in the United States, each child you have increases your lifetime carbon legacy by 5.7 times.
Another option, of course, would be to establish policies that change the behavior of citizens of the developed world who consume a vastly disproportionate share of the Earth's resources and in the process, contribute disproportionately to climate change. As the discussion below indicates, the extent of the change that may be required by the world's largest emitters is substantial.
Consumption Changes: Can the World Afford the Rich?
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The IPCC (Solomon et al 2007) estimates that a cut in the annual global per capita emissions from 2000 levels of 4 tons by 50-80% by 2050 would be necessary in order to keep the temperature rise in the range of 2 degrees. Given the fact that the world’s population is expected to grow by 2 billion people by then, the estimated per capita global average in 2050 has to be reduced to a level between 1.33 tons and 1.5 tons (Moellendorf 2011: 118-119; Baer 2010: 219-221). The significance of these numbers becomes clear when we observe that the per capita emissions in the US in 2008 was roughly 18 tons compared to just over 5 tons for China (World Bank 2012). Without a rapid technological transition toward a radically decarbonized world, life in a country at or near the global average would be one in which “few could be described as well-off” (Socolow and English 2010: 181).
Sources:
For a look at one estimate of how global consumption patterns are likely to change in the years ahead, see Urban world: Cities and the rise of the consuming class, produced by the McKinsey Global Institute.
Sources:
- Baer, P. (2010) “Adaptation: Who Pays Whom? Fairness in Adaptation to Climate Change,” in S. M. Gardiner, S. Caney, D. Jamieson and H. Shue (eds), Climate Ethics: Essential Readings, Oxford and New York: Oxford University Press, pp. 247-62.
- Moellendorf, D. (2011) “Common Atmospheric Ownership and Equal Emissions Entitlements,” in D. Arnold (ed.), The Ethics of Global Climate Change, Cambridge: Cambridge University Press, pp. 104-123.
- Socolow, R., and English, M. (2011) “Living Ethically in a Greenhouse” in D. Arnold (ed.), The Ethics of Global Climate Change, Cambridge: Cambridge University Press, pp. 170-91.
- Solomon et al (2007) “Technical Summary,” in Climate Change 2007: The Physical Basis. Contribution of Working Group I to the Fourth Assessment Report of the Intergovernmental Panel on Climate Change, Cambridge: Cambridge University Press.
- World Bank (2012). “CO2 emissions (metric tons per capita),” http://data.worldbank.org/indicator/EN.ATM.CO2E.PC.
For a look at one estimate of how global consumption patterns are likely to change in the years ahead, see Urban world: Cities and the rise of the consuming class, produced by the McKinsey Global Institute.
Air Conditioning: One Place Where Mitigation Aims and Adaptation Strategies Conflict
The world is likely to get a lot hotter. Air conditioning can help. At least it can help us adapt to changed weather patterns and perhaps save lives that would otherwise be lost to the longer, more intense periods of heat. A 2012 study of deaths in the US from 1900 to 2004 estimated that the chances of dying on an extremely hot day fell 80 percent over the past half-century. Air conditioning is suspected as having much to do with that change. While few US homes had air conditioning in the middle of the 20th century, more than 85% had air conditioning in 2004.
Contrast that with percentages elsewhere in the world where the percentage hovers around or below the double digit level. But things are sure to change. by one estimate, the global demand for air conditioning may grow ten-fold by 2050.
McKinsey Global Initiative (see Urban world: Cities and the rise of the consuming class) predicts that one billion city dwellers “will enter the global consuming class by 2025. Nearly all of the growth will be in tropical regions where air conditioning will be a major purchase item. It will help with local adaptation but it will counteract global GHG mitigation efforts. According to one widely cited estimate published in Scientific American, "India’s 18 million people, just in Mumbai alone could potentially need energy for cooling that is equivalent to a quarter of the demand of the entire US." Even supposing that the new equipment meets the highest efficiency standards, more than a quarter of all global warming will be attributable to the coolant gases used in air conditioning by 2050.
Contrast that with percentages elsewhere in the world where the percentage hovers around or below the double digit level. But things are sure to change. by one estimate, the global demand for air conditioning may grow ten-fold by 2050.
McKinsey Global Initiative (see Urban world: Cities and the rise of the consuming class) predicts that one billion city dwellers “will enter the global consuming class by 2025. Nearly all of the growth will be in tropical regions where air conditioning will be a major purchase item. It will help with local adaptation but it will counteract global GHG mitigation efforts. According to one widely cited estimate published in Scientific American, "India’s 18 million people, just in Mumbai alone could potentially need energy for cooling that is equivalent to a quarter of the demand of the entire US." Even supposing that the new equipment meets the highest efficiency standards, more than a quarter of all global warming will be attributable to the coolant gases used in air conditioning by 2050.
How Important is Recycling?
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Garbage is a major contributor to global warming. Solid waste landfills are the single largest man-made source of methane gas in the United States. Recycling reduces GHG emissions by keeping materials out of the landfill and by reducing the need to continually mine and refine resources needed to produce finished products. Environmentally sympathetic critics pose some important challenges to the public focus on recycling as compared to efforts to achieve more fundamental changes in energy intensive consumption patterns by reducing wastes in production of various goods and packaging materials.
Samantha MacBride's book, Recycling Reconsidered, enters the increasingly controversial debate about how much good recycling actually achieves and how much potential good it may inadvertently block. She points out that while more people in the US recycle than vote, "the goals of recycling--saving the earth (and trees), conserving resources, and greening the economy--are still far from being realized. The vast majority of solid wastes are still burned or buried." She found that recycling prevents only about one-third of all trash from ending up in landfills. The blurb for her book further claims that "recycling as we know it today generates the illusion of progress while allowing industry to maintain the status quo and place responsibility on consumers and local government." What are the potential problems?
One worry is expressed about the extent that recycling is an example of a phenomenon known as single-action bias, where people do one thing and move on, thinking that they have done their part in solving a problem. The website for the Center for Research on Environmental Decisions of the Columbia Earth Institute offers the following cautionary perspective: "Switching to wind or other renewable energies, consuming less meat, conserving daily energy use and eating locally grown food are other effective ways to mitigate climate change, to name but a few. However, if individuals and institutions participate in recycling programs, they may be prone to the single-action bias and feel like they are already doing enough to protect the environment.”
However, one study of "green consumerism" - "Does Changing a Light Bulb Lead to Changing the World? Political Action and the Conscious Consumer" - found evidence of the reverse of the single action bias phenomenon among environmentally conscious consumers. Willis and Schor found that those who chose to do individual green actions were also more involved in other broader political activism.
Another concern is that for some materials the required energy consumption associated with collection, sorting, and recycling can exceed that of producing products from new raw materials. Recycling of waste materials has been analysed from a life cycle perspective generally shows that producing materials from recycled resources is often, but not always, less energy intensive and causes less global warming impact than from virgin resources.
Samantha MacBride's book, Recycling Reconsidered, enters the increasingly controversial debate about how much good recycling actually achieves and how much potential good it may inadvertently block. She points out that while more people in the US recycle than vote, "the goals of recycling--saving the earth (and trees), conserving resources, and greening the economy--are still far from being realized. The vast majority of solid wastes are still burned or buried." She found that recycling prevents only about one-third of all trash from ending up in landfills. The blurb for her book further claims that "recycling as we know it today generates the illusion of progress while allowing industry to maintain the status quo and place responsibility on consumers and local government." What are the potential problems?
One worry is expressed about the extent that recycling is an example of a phenomenon known as single-action bias, where people do one thing and move on, thinking that they have done their part in solving a problem. The website for the Center for Research on Environmental Decisions of the Columbia Earth Institute offers the following cautionary perspective: "Switching to wind or other renewable energies, consuming less meat, conserving daily energy use and eating locally grown food are other effective ways to mitigate climate change, to name but a few. However, if individuals and institutions participate in recycling programs, they may be prone to the single-action bias and feel like they are already doing enough to protect the environment.”
However, one study of "green consumerism" - "Does Changing a Light Bulb Lead to Changing the World? Political Action and the Conscious Consumer" - found evidence of the reverse of the single action bias phenomenon among environmentally conscious consumers. Willis and Schor found that those who chose to do individual green actions were also more involved in other broader political activism.
Another concern is that for some materials the required energy consumption associated with collection, sorting, and recycling can exceed that of producing products from new raw materials. Recycling of waste materials has been analysed from a life cycle perspective generally shows that producing materials from recycled resources is often, but not always, less energy intensive and causes less global warming impact than from virgin resources.
Mckinsey Curves
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A key element of private and public decision making with regard to mitigation efforts is good estimates of the various emissions-reduction opportunities and their associated costs. The McKinsey curves are central to many of the debates, whether or not all the parties to those discussions agree about the cost estimates. McKinsey published their first global greenhouse gas (GHG) abatement curve in January 2007, and they created a comprehensive update with version 2 in January 2009, with a further update (version 2.1) in August 2010 designed to figure in the impact of the financial crisis on carbon economics.
In addition, McKinsey has produced nearly a dozen country-specific cost curves designed to reflect local market realities. The McKinsey cost curves and full reports can be found on their website.
Note that for some of the technologies the working assumption is that there is a large potential for abatement with negative net costs, a finding which is highly controversial among economists. The 2007 cost curves were accompanied by a statement that “almost 40 percent of abatement could be achieved at “negative” marginal costs.” The 2009 report, “Pathways to a Low-Carbon Economy,” (Version 2) also estimates that by 2030 almost 38 Gt of a 70 Gt projection under a business-as-usual scenario could be avoided at a cost that is are far lower in comparison to what some other economists have estimated. The difference arises largely because it assumes the existence of significant potential for abatement with negative net costs, or net economic benefits. Negative-cost opportunities mostly involve energy efficiency measures such as land use changes.
In addition, McKinsey has produced nearly a dozen country-specific cost curves designed to reflect local market realities. The McKinsey cost curves and full reports can be found on their website.
Note that for some of the technologies the working assumption is that there is a large potential for abatement with negative net costs, a finding which is highly controversial among economists. The 2007 cost curves were accompanied by a statement that “almost 40 percent of abatement could be achieved at “negative” marginal costs.” The 2009 report, “Pathways to a Low-Carbon Economy,” (Version 2) also estimates that by 2030 almost 38 Gt of a 70 Gt projection under a business-as-usual scenario could be avoided at a cost that is are far lower in comparison to what some other economists have estimated. The difference arises largely because it assumes the existence of significant potential for abatement with negative net costs, or net economic benefits. Negative-cost opportunities mostly involve energy efficiency measures such as land use changes.
Stabilization Wedges
Source: NRDC: click image for larger view
The C02 reductions axis of the chart on the left uses data and assumptions from the Natural Resources Defense Council's (NRDC) 'wedges' analysis. The wedge analysis is depicts estimated potential emissions reductions 'wedge by wedge,' or sector by sector.
Here are the key assumptions the NRDC relies upon as a strategy for meeting the 2050 target:
Each assumption is worth careful examination and reflection on just what sort of changes in behavior, law, market incentives, and industry practices would be required to realize each one. The scenario supposes not only quite substantial efficiency improvements but a rapid shift to renewables as the source of 40% of electricity supply. Note that the NRDC differs somewhat from the familiar McKinsey estimates: "Relative to the 2030 McKinsey estimates, NRDC assumes 2050 efficiency investments are less cost-effective since some of the easiest measures will already have been realized (although new technologies are constantly emerging such as super-high efficiency LED lighting and super-strong light-weight materials for vehicles).
Moreover, many of the technological assumptions are worth contemplating. Is carbon capture likely to be a viable technology going forward? Is it likely to be economically viable? Compare the Carbon Capture and Sequestration (CCS) cost estimates above using the McKinsey curve. These are among the highest cost per CO2 equivalent to abate.
For a discussion of the NRDC methodology, click here.
Here are the key assumptions the NRDC relies upon as a strategy for meeting the 2050 target:
- End use efficiency reduces total energy demand 50 percent from BaU
- Electricity from renewables increase to 40 percent of supply
- Coal with carbon capture and disposal is deployed in 100 GW of coal-fired electricity generating capacity (equivalent to 200 large plants)
- Fuel economy of new light duty vehicles triples
- Electricity used for 45 percent of miles driven
- Low carbon biofuels provide 36 billion gallons of gasoline equivalent.
Each assumption is worth careful examination and reflection on just what sort of changes in behavior, law, market incentives, and industry practices would be required to realize each one. The scenario supposes not only quite substantial efficiency improvements but a rapid shift to renewables as the source of 40% of electricity supply. Note that the NRDC differs somewhat from the familiar McKinsey estimates: "Relative to the 2030 McKinsey estimates, NRDC assumes 2050 efficiency investments are less cost-effective since some of the easiest measures will already have been realized (although new technologies are constantly emerging such as super-high efficiency LED lighting and super-strong light-weight materials for vehicles).
Moreover, many of the technological assumptions are worth contemplating. Is carbon capture likely to be a viable technology going forward? Is it likely to be economically viable? Compare the Carbon Capture and Sequestration (CCS) cost estimates above using the McKinsey curve. These are among the highest cost per CO2 equivalent to abate.
For a discussion of the NRDC methodology, click here.
Carbon Capture and Sequestration Technologies, aka "Clean Coal"
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Clean coal technology. We hear so much about it, but what exactly is it? Well, it is mostly an industry label for a family of technologies that are designed to reduce the CO2 and other environmental impact (e.g. acid rain) associated with coal-fired electricity generation plants. The first facility of this sort was the Schwarze Pumpe power station which opened in Germany in 2008. The facility captures CO2 and acid rain producing sulfides, separates them, and compresses the CO2 into a liquid. The long-term plan is to inject the CO2 into geological formations for sequestration. Ideas for sequestration include salt formations in depleted gas fields, rock formations of various sorts, and even deep ocean water locations.
There are many impediments to a general assessment. The number of facilities in operation are few, and none are part of large power plants. Thus far, the facilities in operation are demonstration projects, and the added energy costs - as much as 30% more than conventional facility operation costs costs - are a big disincentive against large scale experimentation. The technologies also differ in important respects. And the resolution of so much economic and technological uncertainty over the long haul ultimately depends on how issues of safe storage and secure sequestration are addressed. From marketing campaigns in the US one might assume incorrectly that we have this technology well-worked out and ready to go but for some vague suggestion of inaction in Washington that's holding back progress on that front.
However, market dynamics in the US and Europe have bedeviled assessment of their comparative economic feasibility and stifled innovation. In the US, coal-fired plants are on the decline, in large part due to the declining costs of natural gas powered facilities. For most of 2012, electricity generated by coal plants declined by nearly one-sixth while gas-generated electricity increased by more than one-fourth. Apart from economic considerations affecting energy company investment decisions, natural gas emits about half as much carbon dioxide as coal per kilowatt produced. But the economics of electricity production can be fickle. In the late 1990s utility industries invested heavily in gas and shifted away from coal, just as they are doing today. But then the gas prices spiked after Hurricane Katrina, and the race to coal resumed. Now that prices are again low, we see a different story. According to the Sierra Club, a total of 55 plants have closed recently or have announced plans to shut down, leaving 395 coal-burning plants in the United States, compared with 522 in 2010.
Even now in Europe, where natural gas remains far more expensive, coal plants are on the upswing, especially after Germany made the decision to phase out all nuclear plants. Moreover, Europe's shift toward more coal is facilitated by the ability to take advantage of lower coal prices in the United States, which means that more US coal is being exported. In Asia, where coal is comparatively cheap, it is the fuel of choice with new coal-fired plants coming on line at a rapid pace in places such as China and India. So cheap that even the market prospects for the heavily state-subsidized solar and wind energy industries in China are being decimated. Globally, coal is now the source of 30 percent of the world’s energy, and that represents an increase from about 25 percent in the mid-1990s. Even as roughly 10% of coal-fired plants in the US are slated for closure in the coming few years, and as the world comes to a clearer realization of just how significant the environmental costs of coal are, the World Resources Institute estimates that there are 1,200 new coal-based electricity production projects in the global pipeline.
The point of this market snapshot, of course, is not to predict the path of energy markets - I am not sure who is well-suited to that task - but to show how much of these decisions are driven by a very simple, but frequently shifting economic calculus that reflects virtually nothing having to do with environmental considerations. Coal remains, for now, one of the "low cost incumbents" that is not going to be dislodged by alternative technologies as long as the price does not incorporate the true environmental costs of production.
Natural Gas as an Alternative Source of Energy - A Good Strategy for Mitigating Greenhouse Gases?
A source of much discussion globally is the special report from the World Energy Outlook 2011, produced by the International Energy Agency (IEA) provocatively named "Are we entering a golden age of gas?" Even as the report inserts the obligatory question mark, the Report triumphantly concludes:
"The future for natural gas is bright. Demand has experienced a strong post-crisis recovery, while the North American shale gas boom and expansion of LNG trade have made ample supplies available in the near-term and bolstered future gas supply prospects. With mounting concerns over energy security and global climate change, and renewed debate surrounding the future role of nuclear power, these developments merit a deeper investigation of the prospects for, and the implications of, a golden age of natural gas."
The sequel is "Golden Rules for a Golden Age of Gas" (Released 29 May 2012). The entire World Energy Outlook 2012 report was released on November 12, 2012. Here is what is included in its advance press release: "Drawing on the latest data and policy developments, the 2012 edition of the World Energy Outlook presents analytical insights into trends in energy markets and what they mean for energy security, environmental protection and economic development. It sets out updated projections of energy demand, production, trade, investment and carbon-dioxide emissions, broken down by country, fuel and sector, to 2035."
"The future for natural gas is bright. Demand has experienced a strong post-crisis recovery, while the North American shale gas boom and expansion of LNG trade have made ample supplies available in the near-term and bolstered future gas supply prospects. With mounting concerns over energy security and global climate change, and renewed debate surrounding the future role of nuclear power, these developments merit a deeper investigation of the prospects for, and the implications of, a golden age of natural gas."
The sequel is "Golden Rules for a Golden Age of Gas" (Released 29 May 2012). The entire World Energy Outlook 2012 report was released on November 12, 2012. Here is what is included in its advance press release: "Drawing on the latest data and policy developments, the 2012 edition of the World Energy Outlook presents analytical insights into trends in energy markets and what they mean for energy security, environmental protection and economic development. It sets out updated projections of energy demand, production, trade, investment and carbon-dioxide emissions, broken down by country, fuel and sector, to 2035."
The Growth of Global Gas Demand
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The special report in the 2011 World Energy Outlook contained some blockbuster predictions. For example, it estimated that the share of gas in the global energy mix will rise from 21% today to 25% in 2035. In case you are wondering what the big deal is about such a seemingly small growth in proportionate share of the total energy market represented by gas, that would require a rise of 50% in global demand for gas between 2010 and 2035.
Where might all that gas come from? Take a look at the IEA's map to the right for some clues. If, as the IEA projects, worldwide production of unconventional natural gas could triple to 1.6 trillion cubic meters by 2035, it would require “more than one million new unconventional gas wells worldwide between now and 2035, twice the total number of gas wells currently producing in the United States.”
Gas generated electricity is often described as a “low-regret” option. They are relatively cheap to build, especially compared to nuclear power plants, and the process of generating electricity from gas has been estimated to release up to 50% less carbon dioxide than coal in the best case scenario (AKA Golden Rules in the IEA 2012 special report).
But what would that achievement on its own contribute resolution of the greenhouse accumulation problem? Not so much. The long term trajectory of the Golden Rules case would be consistent with stablizing the GHG concentration levels at around 650ppm with a probable rise in temperature of around 3.5 degrees C. The 2011 Golden Age of Gas report made the point quite clearly that natural gas can be but a small part of any solution.
Where might all that gas come from? Take a look at the IEA's map to the right for some clues. If, as the IEA projects, worldwide production of unconventional natural gas could triple to 1.6 trillion cubic meters by 2035, it would require “more than one million new unconventional gas wells worldwide between now and 2035, twice the total number of gas wells currently producing in the United States.”
Gas generated electricity is often described as a “low-regret” option. They are relatively cheap to build, especially compared to nuclear power plants, and the process of generating electricity from gas has been estimated to release up to 50% less carbon dioxide than coal in the best case scenario (AKA Golden Rules in the IEA 2012 special report).
But what would that achievement on its own contribute resolution of the greenhouse accumulation problem? Not so much. The long term trajectory of the Golden Rules case would be consistent with stablizing the GHG concentration levels at around 650ppm with a probable rise in temperature of around 3.5 degrees C. The 2011 Golden Age of Gas report made the point quite clearly that natural gas can be but a small part of any solution.
Extraction of Unconventional Gas - Not without Social and Environmental Costs
Gasland: The HBO Special Report 2009
This documentary emerges out of one Pennsylvania man's concern for the reports of nearby contamination of wells and streams where hydrologic fracturing techniques - fracking - for the extraction of unconventional gas sources such as shale has increased.
The focus is two-fold. On the one hand, there is an exploration of the possible impact on human health, water, air and wildlife from both the escape of the gas and the use of fracking fluids used in the process of extraction. On the other hand, there is an exploration of the combination of state regulatory inefficacy and federal exemption from the major environmental laws.
The story unfolds as a kind of one-man road trip through the heartland of America's gaslands, where well platforms are growing at an exponential rate. As the film's maker, Josh Fox, observes, he sees the same pattern repeating everywhere: contaminated and indeed flammable water supplies, clusters of unusual health problems such as neurological disorders, and dead animals. The film makes no causal claims - in fact, the point is that we lack scientific evidence and systematic investigation into the impacts.
Here is where the second theme comes into play. At the federal level, the 2005 Energy Policy Act exempts oil and gas production facilities from the reporting requirements of the Safe Drinking Water Act, the regulation by either the Clean Water Act or the Clean Air Act, and many other environmental laws. Simultaneously, the record of state level regulation is one of agency inaction, political influence, and budget cuts of key regulatory agencies.
The film also provides a vidid picture of how the production process works, the nearly 600 non-degradable chemical compounds used in the process, but are not legally required to be reported and not likely to be known by workers and residents in affected areas. The circumstances that provoked the film remain much the same today, except for the fact that the number of unconventional gas wells is increasing and, as the film predicted, the territory of gasland is expanding across the US and the world.
This documentary emerges out of one Pennsylvania man's concern for the reports of nearby contamination of wells and streams where hydrologic fracturing techniques - fracking - for the extraction of unconventional gas sources such as shale has increased.
The focus is two-fold. On the one hand, there is an exploration of the possible impact on human health, water, air and wildlife from both the escape of the gas and the use of fracking fluids used in the process of extraction. On the other hand, there is an exploration of the combination of state regulatory inefficacy and federal exemption from the major environmental laws.
The story unfolds as a kind of one-man road trip through the heartland of America's gaslands, where well platforms are growing at an exponential rate. As the film's maker, Josh Fox, observes, he sees the same pattern repeating everywhere: contaminated and indeed flammable water supplies, clusters of unusual health problems such as neurological disorders, and dead animals. The film makes no causal claims - in fact, the point is that we lack scientific evidence and systematic investigation into the impacts.
Here is where the second theme comes into play. At the federal level, the 2005 Energy Policy Act exempts oil and gas production facilities from the reporting requirements of the Safe Drinking Water Act, the regulation by either the Clean Water Act or the Clean Air Act, and many other environmental laws. Simultaneously, the record of state level regulation is one of agency inaction, political influence, and budget cuts of key regulatory agencies.
The film also provides a vidid picture of how the production process works, the nearly 600 non-degradable chemical compounds used in the process, but are not legally required to be reported and not likely to be known by workers and residents in affected areas. The circumstances that provoked the film remain much the same today, except for the fact that the number of unconventional gas wells is increasing and, as the film predicted, the territory of gasland is expanding across the US and the world.
Agricultural Adaptation Strategies
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Adapting Agriculture to Climate Change is a collection of over 30 essays that summarize the various updated climate change scenarios for Australia. As the book liner notes indicate, "It includes chapters on socio-economic and institutional considerations for adapting to climate change, greenhouse gas emissions sources and sinks, as well as risks and priorities for the future." What's most interesting about the book is the focus on Australia's primary agricultural sectors, including "horticulture, forestry, grains, rice, sugarcane, cotton, viticulture, broadacre grazing, intensive livestock industries, marine fisheries, and aquaculture and water resources." The book relies upon a series of case studies in order to demonstrate some of the main options for climate change adaptation within each industry.
Genetically Engineered Crops as an Adaptation Strategy?
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One worry about increase temperature and its effect on agriculture is the effect of heat waves on water, initially by creating drought, but over the longer term, by reducing the groundwater in deep aquifers that feed lakes, rivers, and streams.
Another worry about higher temperatures is the prospect that traditional staple crops might not fare well where they once did. Some agronomists have argued that with temperatures above a certain threshold, yields fall sharply.
But climate change may bring problems for agriculture for reasons other than heat levels that exceed crop species tolerance levels. Weather pattern disruption may be a more potent challenge to agriculture in some locations. The same variability in weather patterns that produces draught can produce floods when it rains heavily in normally dry seasons and dries up during wetter seasons when crops are growing. Shorter, wetter, colder growing seasons can cripple some crops as surely as longer, drier, warmer ones can destroy others.
One avenue of adaptation would be the genetic engineering of new staple crop species, ones that are more resistant to drought, flooding, extreme heat, and the new breeds of pests that will surely follow. One worry is that parts of the world most likely to be hit first and worst by extreme changes in climate affecting agricultural productivity lack the investment in the kinds of research that could aid in their adaptation.
A 35 minute discussion, Feeding A Hotter, More Crowded Planet, from NPR's Science Friday serie (2011) features Lester Brown, author, "World on the Edge: How to Prevent Environmental and Economic Collapse", founder and president, Earth Policy Institute, Gawain Kripke, director, policy and research, Oxfam America, Gerald Nelson, senior research fellow, International Food Policy Research Institute.
Genetic modifications have not been developed for many of the main staple crops in Africa, in part because of the enormous investment costs associated with their scientific development, marketing, and government approval processes. A discussion paper, The Use of GM Crops in Developing Countries, by the Nuffield Council on Bioethics is a follow-up to its earlier report on ethical and social issues related to GM crops, in which the Nuffield Council concluded that this technology should be made available to people in developing countries who want them. Building upon this foundation, the more recent paper seeks to address the debate over GM crops in its political, economic, cultural, and historical contexts. Building off of its 1999 Report, the Council concludes that, “there is a moral imperative to make GM crops readily and economically available to people in developing countries who want them” in order to strengthen their respective agricultural sectors and improve global food security. The report notes that Sub-Saharan Africa and parts of South and Central Asia saw few initial gains from Green Revolution technologies, and food security and poverty have continued to increase due primarily to subsequent water shortages, soil depletion, and the emergence of new pests and diseases. The conclusion is that the most pervasive, sustainable solution continues to be the improvement of small farm productivity, for which GM technology may play a pivotal role. One of the main conclusions from a study that examines a large variety of GMOs in diverse ecological settings is that “possible costs, benefits, and risks associated with particular GM crops can be assessed only on a case by case basis” (xiv). The Report also criticizes the European reliance upon a risk-averse precautionary principle approach, and it argues that because most current privately-funded research on GM crops serves the interests of large-scale developed world farmers, there must be “a major expansion of public GM-related research into tropical and sub-tropical staple foods, suitable for the needs of small-scale farmers in developing countries” (xvi-xvii).
A skeptical response to the promotion of GM crops as an important part of the adaptation strategies for dealing with global warming is the report by Friends of the Earth, Europe. Click on the image above for the link to the full report.
Another worry about higher temperatures is the prospect that traditional staple crops might not fare well where they once did. Some agronomists have argued that with temperatures above a certain threshold, yields fall sharply.
But climate change may bring problems for agriculture for reasons other than heat levels that exceed crop species tolerance levels. Weather pattern disruption may be a more potent challenge to agriculture in some locations. The same variability in weather patterns that produces draught can produce floods when it rains heavily in normally dry seasons and dries up during wetter seasons when crops are growing. Shorter, wetter, colder growing seasons can cripple some crops as surely as longer, drier, warmer ones can destroy others.
One avenue of adaptation would be the genetic engineering of new staple crop species, ones that are more resistant to drought, flooding, extreme heat, and the new breeds of pests that will surely follow. One worry is that parts of the world most likely to be hit first and worst by extreme changes in climate affecting agricultural productivity lack the investment in the kinds of research that could aid in their adaptation.
A 35 minute discussion, Feeding A Hotter, More Crowded Planet, from NPR's Science Friday serie (2011) features Lester Brown, author, "World on the Edge: How to Prevent Environmental and Economic Collapse", founder and president, Earth Policy Institute, Gawain Kripke, director, policy and research, Oxfam America, Gerald Nelson, senior research fellow, International Food Policy Research Institute.
Genetic modifications have not been developed for many of the main staple crops in Africa, in part because of the enormous investment costs associated with their scientific development, marketing, and government approval processes. A discussion paper, The Use of GM Crops in Developing Countries, by the Nuffield Council on Bioethics is a follow-up to its earlier report on ethical and social issues related to GM crops, in which the Nuffield Council concluded that this technology should be made available to people in developing countries who want them. Building upon this foundation, the more recent paper seeks to address the debate over GM crops in its political, economic, cultural, and historical contexts. Building off of its 1999 Report, the Council concludes that, “there is a moral imperative to make GM crops readily and economically available to people in developing countries who want them” in order to strengthen their respective agricultural sectors and improve global food security. The report notes that Sub-Saharan Africa and parts of South and Central Asia saw few initial gains from Green Revolution technologies, and food security and poverty have continued to increase due primarily to subsequent water shortages, soil depletion, and the emergence of new pests and diseases. The conclusion is that the most pervasive, sustainable solution continues to be the improvement of small farm productivity, for which GM technology may play a pivotal role. One of the main conclusions from a study that examines a large variety of GMOs in diverse ecological settings is that “possible costs, benefits, and risks associated with particular GM crops can be assessed only on a case by case basis” (xiv). The Report also criticizes the European reliance upon a risk-averse precautionary principle approach, and it argues that because most current privately-funded research on GM crops serves the interests of large-scale developed world farmers, there must be “a major expansion of public GM-related research into tropical and sub-tropical staple foods, suitable for the needs of small-scale farmers in developing countries” (xvi-xvii).
A skeptical response to the promotion of GM crops as an important part of the adaptation strategies for dealing with global warming is the report by Friends of the Earth, Europe. Click on the image above for the link to the full report.
Geoengineering
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There have been a number of provocative proposals for addressing GHG concentration in the atmosphere by various forms of geoengineering. One of the more widely cited discussions is the 2009 article "Geoengineering Option (click for pdf), by David Victor et al in the journal Foreign Affairs.
There are all sorts of ideas floating around. One proposal is to dump iron filings into the ocean, thereby creating a giant algae bloom that would sequester carbon and thereby combat climate change.
Even Bill Gates has invested in geoengineering research, including holdings in Intellectual Ventures, a company that is developing the “StratoShield,” a 19-mile-long hose suspended by helium balloons that would disperse sun-blocking sulfur dioxide particles into the sky.
A somewhat more radical suggestion (perhaps) involves the genetic modification of humans, rather than genetically modifying crops for adaptation purposes or embarking on risky geoengineering projects for the sake of mitigation. In a paper called “Human Engineering and Climate Change,” published in the journal Ethics, Policy, & the Environment, S. Matthew Liao, Anders Sandberg, and Rebecca Roache argue that “the biomedical modification of humans to make them better at mitigating climate change … potentially offers an effective means of tackling climate change. …”
Source of graphic: Victor et al, 2009.
There are all sorts of ideas floating around. One proposal is to dump iron filings into the ocean, thereby creating a giant algae bloom that would sequester carbon and thereby combat climate change.
Even Bill Gates has invested in geoengineering research, including holdings in Intellectual Ventures, a company that is developing the “StratoShield,” a 19-mile-long hose suspended by helium balloons that would disperse sun-blocking sulfur dioxide particles into the sky.
A somewhat more radical suggestion (perhaps) involves the genetic modification of humans, rather than genetically modifying crops for adaptation purposes or embarking on risky geoengineering projects for the sake of mitigation. In a paper called “Human Engineering and Climate Change,” published in the journal Ethics, Policy, & the Environment, S. Matthew Liao, Anders Sandberg, and Rebecca Roache argue that “the biomedical modification of humans to make them better at mitigating climate change … potentially offers an effective means of tackling climate change. …”
Source of graphic: Victor et al, 2009.