«DIRECT TESTIMONY OF JAMES E. HANSEN Q. Please state your name and business address. A. My name is James E. Hansen. My business address is 2880 ...»
If there is a near-term moratorium in developed countries on new coal-fired power plants that do not sequester CO2, a similar moratorium 10 years later in developing countries, and if over the period 2025-2050, existing coal-fired power plants are phased out linearly, CO2 can be kept below 450 ppm. It will also be necessary to stretch conventional oil and gas supplies via economic incentives (a price on carbon emissions) that drive technology development needed for improved energy efficiency and renewable energies. A moderate gradually rising price on emissions can be achieved in a variety of means including individual emission allowances, cap-and-trade or taxes, but for maximum effectiveness it must be accompanied by standards, for example on building and vehicle efficiencies, and barriers to efficiency should be removed, e.g., by decoupling utility profits from the amount of energy sold. Important supplementary actions that will help stabilize climate sooner are reduction on non-CO2 climate forcings and actions that draw down atmospheric CO2, especially improved agricultural practices that sequester carbon in the soil, better preservation of forests, and perhaps power plants that burn biofuels and capture and sequester the CO2.
Figure 31. The most difficult aspect of the alternative scenario is stabilization of CO2 at a level of, at most, about 450 ppm.
Given that it is impractical to capture CO2 produced by mobile and other small sources burning oil or gas, and given the magnitude of potential emissions from coal, it is apparent that the one practical way to limit atmospheric CO2 is to limit future coal use to places where CO2 is captured and sequestered.
Figure 32. Business-as-usual use of all three conventional fossil fuels yields a doubling of pre-industrial CO2 levels.
This estimate does not include unconventional fossil fuel use or potential positive biosphere feedbacks that might accompany large climate response to doubled CO2.
Figure 33. Phase-out of coal use, except where CO2 is captured and equestered, yields maximum CO2 under 450 ppm, even with oil and gas reserves used entirely, including anticipated oil and gas discoveries.
Figure 34. Stretching of conventional fossil fuel supplies is essential to prevent irrational behavior of a drunken addict.
The future beyond fossil fuel addiction is an attractive world, provided we do not damage the Earth irreparably in the transition. The only way to do that successfully is to wean ourselves off fossil fuels now, before we pass the climate tipping points. Environmental destruction, for the sake of squeezing every drop of black stuff from the Earth does not make sense.
Pre-industrial to Present Climate Forcings with Primary Indirect Effects
Figure 35. There is approximately enough potential for reduction of methane, tropospheric ozone, CFCs and black soot to restore planetary energy balance, the present imbalance being in the range 0.
5-1 W/m2. There would be large side benefits in reduction of these air pollutants, which are damaging to human health and agricultural productivity, especially in the developing world. In evaluating the potential to reduce non-CO2 forcings to mitigate climate change, it is important to include the ‘efficacy’ of each forcing (Hansen et al. 2005). Thus, for example, although the efficacy is low for black soot on global average, limitations on soot emissions in the Arctic would be very effective, suggesting the importance of placing constraints on ships and other sources within the Arctic.
Figure 36. Ratio of annual increase of CO2 in the atmosphere divided by annual fossil fuel CO2 emissions.
The long-term mean is ~57% with negligible trend.
Figure 37. Power plants that burn biofuels could be used to draw down atmospheric CO2, with the CO2 sequestered locally in appropriate geologic formations or piped to the coast where it could be injected beneath ocean sediments where it is inherently stable.
The biofuels should be natural grasses or other cellulosic fibers farmed in a way that promotes soil conservation and carbon storage in the soil, e.g., using no till practices.
Figure 38. The water contributing one meter of sea level rise could be stored in a lake formed by placing 200 meter high dams at the indicated locations in Canada.
This lake would cover a substantial area that is presently inhabited, providing an example of how difficult it would be to adapt to substantial disintegration of ice sheets.
Lake Wobegone II Figure 39. The water contributing one meter of sea level rise could be stored in a lake formed by placing a 242 meter high dam at the indicated location in Russia. This lake would cover a substantial area that is presently inhabited, providing an example of how difficult it would be to adapt to substantial disintegration of ice sheets.
Figure 40. It is still feasible to keep atmospheric CO2 well below 450 ppm and to keep additional global warming well below 1°C, but only if actions are taken quickly to get onto a new pathway.
Business-as-usual growth of emissions, for even another decade, eliminates that possibility: atmospheric CO2 will reach 400 ppm by 2015, and with a further 20% increase of CO2-producing infrastructure, it becomes infeasible to avoid dangerous climate change. The principal action required to achieve the alternative scenario is a moratorium on new coal-fired power plants without sequestration in the West, followed by a similar moratorium in developing counties within a decade.
Figure 41. Responsibility for current climate change is proportional to cumulative emissions of long-lived greenhouse gases, not current emissions (Hansen et al.
2007b). Thus the United States has a responsibility more than a factor of three greater than any other country, and will continue to be most responsible for decades even though China is passing the United States in current emissions. Europe is responsible for more than 30% and the U.S. plus Canada and Australia are responsible for another 30%.
Figure 42. Per capita CO2 emissions, with countries ranked in order of total emissions.
Figure 43. Production of CFCs stabilized (no new factories) immediately after the first warning that the may affect stratospheric ozone.
Production began to increase in the 1980s for refrigeration in developing countries, but after the Montreal Protocol and its subsequent tightenings production fell rapidly. Developing countries were allowed 10 years longer than developed countries to phase out CFC use and technical assistance with alternative chemicals was provided by developed countries through the World Bank.
Figure 44. All parties deserve credit for the success in avoiding ozone catastrophe.
Scientists provided a clear message, the media reported it, the public was responsive by reducing frivolous uses of CFC for spray cans, and governments, led by the United States took leadership roles in defining solutions. Special interests, specifically Dupont Chemical company, initially disputed the science, but eventually focused upon substitute chemicals.
Figure 45. The global warming story differs markedly from the ozone story.
Scientists have perhaps not made clear the emergency that is upon us. Special interests have been particularly effective in affecting the media and governments so as to avoid actions needed to stem global warming.
Figure 46. Responsibility for the current situation rests, in my opinion, with all of the parties 1 through 5a.
Unfortunately it is the younger and future generations, bearing little if any responsibility, who will be faced with most of the consequences and will need to pay for our profligate use of natural resources.
Figure. 47. By far the most important action needed to get the world onto a track that will stabilize climate is an immediate moratorium on new coal-fired power plants in the developed world, to be followed by a similar ban in developing countries within a decade.
Figure 48. Failure of governments to take actions needed to preserve creation, and the priority that governments have given to special interests over the common good, make it clear that citizens need to place greater priority on preservation of creation in exercising their electoral prerogatives.
Candidates for office have begun to make note of the climate issue and utter fuzzy words in support of the planet and the environment. However,
actions proposed are, in most cases, ineffectual, not incorporating the two essential needs for stabilizing climate:
phase-out of dirty coal and a gradually rising price on carbon emissions.
Figure 49. CO2 emissions are increasing at a rate at or above IPCC “business-as-usual” scenarios.
Other greenhouse gases are increasing at slower rates.
Climate Forcing by Long-Lived Greenhouse Gases
Figure 50. Climate forcing by all long-lived greenhouse gases is increasing at a rate that falls below all IPCC scenarios, about half-way between the IPCC and alternative scenarios.
The last two point (2005 and 2006) on the observations may be somewhat misleading, as they are 3-year and 1-year means, while the other points are 5-year means. Because the 2006 CO2 increase was relatively small, that decreases the 2005 and 2006 results, which may be modified when 2007 and 2008 allow full 5-year means to be calculated.
Figure 51. We have reached a climate crisis, but there are feasible actions that could defuse the global warming time bomb, and these actions have many ancillary economic and environmental benefits.
Figure 52. Based on experience, I believe that the difficulty in communication about global warming and the lack of success in obtaining actions needed to reduce global warming are, at least in part, a consequence of the role of special interests who seem to place inordinate priority on short-term profits. Although global warming has received much attention of late, there remains a large gap between what is understood by the relevant scientific community and what is known by those who need to know, the public and policy-makers. I find it puzzling that conservatives, and I consider myself to be a moderate conservative, are not more concerned about preserving creation. I believe that the best hope for achieving the actions needed to preserve climate for the benefit of all residents of the planet is to draw attention to the generational inequity, the burden that we could leave for our children and grandchildren. For this purpose it is desirable that young people themselves become educated on the matter and help communicate with their elders. One word of caution: when fossil fuel companies start putting ‘green’ advertisements in the newspaper, throw those in the waste bin straightaway and instead check what fraction of their earnings are being invested in energy sources that do not produce greenhouse gases.