Here are some recent articles and presentations:

Seminar at World Bank, September 2008. Some of the latest results on the economics of global warming, click here.

“Who’s Afraid of a Big Bad Oil Shock?” Prepared for the Brookings Panel on Economic Activity, Fall 2007. When the U.S. invaded Iraq in March 2003, many economists feared that the war would lead to a sharp decline in Iraqi oil production, a spike in oil prices, and a woeful economy that would follow the scripts of the oil shocks of 1973, 1978, and 1990. What happened and why is analyzed here. For the prepublication draft, background notes, and an Excel sheet with the data, click here.

The results of the latest DICE model is available in A Question of Balance: Economic Modeling of Global Warming (Yale Press, 2008). A prepublication version (with a few remaining typos and problems) is available, click here, click here (version of February 2008). The documentation as lab notes is available, click here (version of October 5, 2007).

A Review of the Stern Review on the Economics of Global Warming (May 2, 2007), forthcoming, Journal of Economic Literature. “It appears that no two global warming policies on earth are farther apart than the White House and 10 Downing Street. Because it has conclusions that are so different from most economic studies, the present note examines the reasons for this major difference. Is this radical revision of global-warming economics warranted? …” Click here for the study.

“Critical Assumptions in the Stern Review on Climate Change,” Science, 13 July 2007, Vol. 317. no. 5835, pp. 201–202 for a brief synopsis of the issues concerning the discount rate and the Stern Review, Click here.

“Key Potential Improvements in Statistics and Data for Policies Concerning Global Warming: The Role of Federal Statistical Agencies,” Prepared for National Research Council (U.S.) Committee on National Statistics, May 10, 2007 This report focuses on the statistical data needs in the social sciences for understanding global warming. The five areas that appear to be critical for improving our understanding and modeling are scientific data, environmental data, energy and emissions data, improved accounting systems, and international data. For the paper, click here.

“To Tax or Not to Tax: Alternative Approaches to Slowing Global Warming,” volume 1, issue 1, winter Review of Environmental Economics and Policy, 2007, pp. 26–44. How can countries best coordinate their policies to slow global warming? This study reviews different approaches to the political and economic control of global public goods such as global warming. It compares quantity-oriented mechanisms like the Kyoto Protocol with price-type control mechanisms such as internationally harmonized carbon taxes. The analysis focuses on such issues as the relationship to ultimate targets, performance under conditions of uncertainty, volatility of induced carbon prices, the inefficiencies of taxation and regulation, potential for corruption and accounting finagling, and ease of implementation. It concludes that price-type approaches such as carbon taxes have major advantages for slowing global warming. For a copy, click here.

The Economics of Hurricanes in the United States, December 21, 2006.Was 2005 a harbinger of a new era of increasingly destructive hurricanes? Does it reflect global warming? What kinds of policies should be undertaken to cope with the rising seas and possibility of more intense hurricanes? Should cities like New Orleans be abandoned to return to salt marshes or ocean? These deep questions cannot be definitively answers, but this note will provide some suggestions. Click here for pdf. (For background notes on data and methods, click here. For the spreadsheet with data, click here.)

“Alternative Measures of Output in Global Economic-Environmental Models: Purchasing Power Parity or Market Exchange Rates?” Energy Economics, 2007, no 3. Prepared for Meeting of IPCC Expert Meeting on Emission Scenarios, US- EPA Washington, DC, January 12-14, 2005. This study analyzes the question of the use of purchasing-power parity versus market exchange rates in constructing global economic models. It concludes that the best approach is to use superlative PPP accounts; this approach uses cross-sectional PPP measures for relative incomes and outputs and relies on national accounts price and quantity indexes for time-series extrapolations. For a pdf version, click here.

"An Economic History of Computing" (Journal of Economic History, March 2007). How has the power of computing changed over the last century and a half? Was progress before the microprocessor as rapid as over the last 2 decades? How well do official prices capture the increase in computational power? When will humanoid computers be on the scene? To find out, for a pdf version, click here

"Economic Consequences of a War in Iraq." (December 2002) This study examined the likely economic costs of the war in Iraq four months before the war began. It predicted the costs might mount and observed:

“Might historians look back and conclude that the United States showed signs of wooden-headedness in its determination to overthrow Saddam in Iraq? In contrast to the clear danger from terrorist activities, there is no imminent threat from Iraq. A war in Iraq threatens to claim the scarce resources and attention of the United States for many years. A stagnant economy, fiscal deficits, a persistent crisis of corporate governance, growing health-care problems, and trouble spots in the rest of the world – all these would take a back seat if the United States gets bogged down in issues of war and peace in Iraq….Particularly worrisome are the casual promises of postwar democratization, reconstruction, and nation-building in Iraq. The cost of war may turn out to be low, but the cost of a successful peace looks very steep. If American taxpayers decline to pay the bills for ensuring the long-term health of Iraq, America would leave behind mountains of rubble and mobs of angry people. As the world learned from the Carthaginian peace that settled World War I, the cost of a botched peace may be even higher than the price of a bloody war.”

A non-technical version appeared in the New York Review of Books, December 2002, click here . The full study, published by the American Academy of Arts and Sciences, is available in electronic form from  the Academy web site, click here . It is also available in a pdf version (500 KB), click here

“Geography and Macroeconomics: New Data and New Findings” Proceedings National Academy of Sciences (US), March 7, 2006, vol. 103, no. 10, pp. 3510-3517. Click here.

The linkage between economic activity and geography is obvious as populations cluster mainly on coasts and rarely on ice-sheets. Past studies of the relationships between economic activity and geography have been hampered by limited spatial data on economic activity. The present study introduces new data on global economic activity, the G-Econ database, which measures economic activity for all large countries, measured at 1º latitude by 1º longitude scale. The methodologies for the study are described. Three applications of the data are investigated. First, the puzzling “climate-output reversal” is detected, whereby the relationship between temperature and output is negative when measured on a per capita basis and strongly positive on a per area basis. Second, the database allows better resolution of the impact of geographic attributes on African poverty, finding geography relatively unimportant in causing relative poverty. Finally, we can use the G-Econ data to provide estimates of the economic impact of greenhouse warming, with larger estimates of damage than past studies.

To go to the webpage with the study and background, click here.

“After Kyoto: Alternative Mechanisms to Control Global Warming,” American Economic Review, May 2006. This study reviews different approaches to the political and economic control of global public goods like global warming. It compares quantity-oriented control mechanisms like the Kyoto Protocol with price-type control mechanisms such as internationally harmonized carbon taxes. It concludes that price-type approaches using carbon taxes are likely to be more effective and more efficient. For the AER at the meetings, click here. For the longer background paper, click here.

"The Health of Nations" and “Irving Fisher and the Health of Nations.” The Business Week of April 24, 2002 and The New York Times of November 11, 2001 referred to a paper evaluating the impact of improvements in health status of augmented income. The surprising result is that improvements in the health status of the population over the 20th century have made as much contribution to economic welfare as all other consumption increases combined. For the recent version from The American Journal of Economics and Sociology, Vol. 64, No. 1 ( January, 2005), click here.

“The Question of Excessive Military Spending in the United States,” Prepared for the Annual Meetings of the American Economic Association, Boston, Massachusetts, Session on “The Costs of War,” January 8, 2005. This comment addresses the cost of a large military establishment. The remarks that follow touch on five points. First, I describe the numbers involved. Second, I ask whether the large military spending is justified by external threats. Third, I raise the issue of strategic and budgetary inertia. The next question I address is whether all these resources are burning a hole in our pocket. The final comment examines the role of loose budget constraints on policy outcomes. Click here.

"Paul Samuelson and Global Public Goods,” in Michael Szenberg et al., Samuelsonian Economics, Oxford, 2006. What are the common blessings and scourges of mankind? Consider issues as disparate as greenhouse warming and ozone depletion, the Internet and William Shakespeare, terrorism and money laundering, the discovery of antibiotics and nuclear proliferation. These are examples of global public goods, one of the great concepts in economics which flowed from the fertile mind of Paul Samuelson, whom this essay commemorates. For the prepublication version, click here.

“A Retrospective on the Postwar Productivity Slowdown,” September 27, 2004. Using a new data set, this paper reviews the sources of the productivity slowdown of the 1970s. Click here.

“Abrupt Climate Change,” with R. B. Alley, J. Marotzke, J. T. Overpeck, D. M. Peteet, R. A. Pielke Jr., R. T. Pierrehumbert, P. B. Rhines, T. F. Stocker, L. D. Talley, J. M. Wallace, Science, March 28, 2003, pp. 205-210. Highlights from the recent National Academy of Sciences Report on Abrupt Climate Change, click here .

Abrupt Climate Change: Inevitable Surprises (December 2001). This National Academy of Sciences review of the stunning discoveries about the jagged history of climate, with changes in climate as large as half an ice age in a decade. For an online version of the report, go to http://www.nap.edu/books/0309074347/html/ . 

"Modeling Induced Innovation in Climate-Change Policy" (April 2001). Virtually all studies of environmental and climate-change policy —  indeed of virtually all aspects of economic policy —   have generally sidestepped the thorny issue of induced innovation. This study lays out a well-defined model and includes it in the DICE model of greenhouse warming. The resulting impact of including induced innovation is close to incredible. To find out more, for a pdf version, click here .

"The Economic Impacts of Abrupt Climate Change" (January 1999, August 1999, March 2001). This study surveys the economic impacts and modeling of abrupt climate change. It has been presented at two workshops of the National Academy of Sciences and at a Yale/NBER/IIASA Workshop on Abrupt Climate Change. This version is the original version from January 1999. For a pdf version, click here.