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Center for Global Studies Policy Brief 1

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Center for Global Studies Policy Brief 1 Center for Policy Global Studies Brief 1 No 1, May 2008 Some Hard Truths You Should Know About the About Global Warming Center for Global Studies The Center for Global Studies (CGS), the Michael E. Schlesinger, Climate Research Group, Professor of principalSummary academic arm of International Atmospheric Sciences, University of Illinois at Urbana- Programs and Studies (IPS), is responsible Champaign, [email protected] for globalizing the University of Illinois at Urbana-Champaign’s research, teaching, and outreach programs. Since 2003, CGS has been designated as a National Resource If the Earth’s atmosphere did not contain water vapor, carbon dioxide (CO 2) Center (NRC) under the U.S. Department of and ozone, which make up less than 0.25% of its composition, the average sur- Education’s Title VI grant program. face temperature would be 0°F – so cold there would be no liquid water and, CGS has a four part mission. First, the thus, no life. The fact that the temperature is a life-supporting 60°F is due to Center promotes and supports innovative these seemingly minor greenhouse gases (GHG’s). On Venus the atmosphere research to define what globalization as a is all CO 2, the surface pressure is 90 times that on Earth, and the greenhouse contested notion is, to identify the multiple warming is 900°F, about twice as hot as your home oven can get! The natural and cumulative impacts of the powerful greenhouse effect is indisputable. forces driving this process, and to make this knowledge known to interested parties th Since the beginning of the industrial revolution in mid-18 century, human- around the globe. ity has added CO to the atmosphere by burning fossil fuels (coal, oil and natu- 2 Second, CGS works closely with ral gas) and by deforestation. This added CO 2 decreased the radiation emitted UIUC's nine colleges, multiple disciplinary out to space by the Earth such that it was less than the radiation absorbed by and professional units, and faculty and stu- the Earth from the Sun. This caused the Earth’s surface and lower atmosphere dents to globalize the research, teaching, to warm towards restoring the balance. This is the human-caused greenhouse and engagement missions of the university. effect. Third, CGS consults with universities From the beginning of the industrial revolution until now the United States and faculty who aim to develop global stud- ies research and teaching programs. and Europe added most of the CO 2 to the atmosphere. Soon this role will pass to the developing countries, especially China and India. There are 7 times as Fourth, CGS works to make the knowl- many people there as in the United States, each of whom, on average, uses 1/6 edge and teaching programs on all aspects as much energy as a person in the U.S. If these countries develop as did the of globalization available to teachers and students in Illinois, the United States, and U.S., then they alone will emit 42 times as much CO2 as the U.S., which will be 10 times the emission by the entire world now. Clearly, reducing the emis- elsewhere around the world from K-16. These resources are also accessible to busi- sion of GHG’s is a geopolitical problem of unprecedented scope. nesses, professionals, media, governmental I have analyzed the observed record of average surface-air temperature from agencies, civic organizations, and all mem- the mid-19 th century to the end of the 20 th century using a simple mathematical bers of the interested public concerned with global problems and how to solve them for climate model to simulate this quantity for many different possible causes [1]. the benefit of peoples everywhere. This analysis showed that the human-caused greenhouse effect was the pre- dominant cause of the observed warming, with another contribution by a natu- ral oscillation of the Atlantic thermohaline 1 circulation [2]. For more information, please visit www.cgs.uiuc.edu , send email to [email protected] , or call 1. The heat-and-salt driven circulation. 1-217-265-5186. International Programs and Studies University of Illinois at Urbana-Champaign 2 Policy Brief Author Today there are many worrisome signs in greenhouse Earth, especially the loss of ice in the Greenland ice sheet and the complete loss of the Larsen B ice Michael E. shelf in West Antarctica. Clearly the climate is changing significantly because Schlesinger , Professor of the human-caused greenhouse effect. of Atmospheric Sci- ences, University of I have also found that for a moderate warming by the end of this century, the Illinois at Urbana- countries that emit CO 2 – which are located in temperate and high latitudes – Champaign (UIUC), slightly benefit in terms of market impacts, especially agriculture. But countries received his B.S. and that emit little or no CO 2 – which are located in tropical latitudes, particularly in M.S. degrees in Engi- Africa – are harmed by a reduction in their gross domestic product [3]. Clearly neering, and his Ph.D. this is not equitable and reverses the “Polluter Pays Principle” of international degree in Meteorology, environmental law. Furthermore, for end-of-century warming that is not moder- all from the University of California, Los ate, all countries are harmed [4]. Angeles. Professor Schlesinger directs the UIUC Climate Research Group (CRG) I have calculated the expected values of the changes in average surface-air within the Department of Atmospheric Sci- temperature and sea level this century for 4 possible future emission scenarios ences. He is an expert in the modeling, simu- absent climate policy, 3 possible climate sensitivities 2, and 2 possible melt rates lation and analysis of climate and climate for the Greenland ice sheet, each weighted by a subJective probability. The re- change, with interests in simulating and un- sults in 2100 are 4°F and 1.6 feet, respectively, both relative to year 2000 [5]. derstanding past, present and possible future Even more disquieting, both temperature and sea level continue to increase into climates, climate impacts and climate policy. the 22 nd century. I also calculated the effect of four ‘1% solutions’ wherein ei- Prof. Schlesinger is a member of Illinois ther the global or regional-only emissions of greenhouse gases are reduced line- Governor Rod Blogavich’s Illinois Climate arly to zero by 1% per year beginning in 2010. Only for the global ‘1% solu- Change Advisory Group and contributor to tion’ does the temperature increase level off by 2100, albeit the sea-level rise the United Nations Intergovernmental Panel does not. This shows the importance of having the entire world reduce its emis- on Climate Change (IPCC), which won the sion of GHG’s. 2007 Nobel Peace Prize. His research currently focuses on: (1) simu- I have examined the effect of hedging against our uncertain climate future by lating and understanding the effects on cli- imposing a tax on carbon now compared to 30 years from now [6], in both cases mate of a human-induced melting of the the tax increasing annually at the then rate of interest. Results were obtained Greenland ice sheet; (2) simulating and un- over two uncertain quantities, the climate sensitivity and the maximum allowed derstanding the influence of the sun on cli- global warming. Imposing the tax now not only holds open options that are mate in terms of its changes in total solar foreclosed by delaying the tax by 30 years, the adJustment cost 3 is less for the irradiance, ultraviolet radiation and precipi- current tax than for the tax delayed by 30 years. Thus uncertainty is not a Justi- tating energetic electrons; (3) understanding fication for doing nothing now, rather it is the reason for acting now. and reducing the uncertainty in the estimated climate sensitivity; (4) determining the ef- Another uncertainty of our future climate is whether or not there are tipping fects on past and future climate of the sun, points, such as a shutdown of the Atlantic thermohaline circulation [7] and the sulfate aerosols – both of volcanic and an- loss of the Greenland ice sheet, and, if they exist, how close we are to them. thropogenic origin – and natural variability; The only way to know for certain is after the fact of crossing one. But, clearly (5) performing integrative assessment of then it will be too late to mitigate that crossing, and instead we will then have to climate change, including the impacts of climate change and adaptation and 2 mitiga- suffer and adapt to its climatic consequences. Thus the most important climate tion responses; (6) further developing the factor to hedge against is the crossing of such uncertain tipping points. To do robust adaptive decision strategy; and (7) this we must make the transition this century, as quickly as we can, from the simulating and understanding the coupled Greenhouse-Gas-Emission Age to the Post-Greenhouse-Gas-Emission Age. To climate-chemistry system, including the in- not do so would be to play Russian Roulette with the Earth's climate. fluences of the sun – both irradiance and energetic electron precipitation – and volca- What can you do to reduce your “carbon footprint”? You can go to the web- noes. site of the Oregon State University Campus Carbon Challenge He recently edited Human-Induced Climate Change: An Interdisciplinary Assessment . 2. The amount the Earth would warm after restoring the radiation balance that was disturbed by a (Cambridge UP, 2007) Additional informa- doubling of the pre-industrial CO2 concentration. tion is located on the CRG Homepage at: 3. The difference between the discounted Gross World Productivity (DGWP) of the http://crga.atmos.uiuc.edu/ policy and the DGWP of the least-cost policy, that is, the difference in DGWP due to not knowing with certitude the values of climate sensitivity and maximum allowed global warming.
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