Drawing upon a variety of different criteria, many nations have introduced proposals to differentiate the reductions in carbon emissions that would be required of industrialized nations in the short to medium term. This paper considers the relationship of these proposals to their underlying conceptions of equity, and to the self-interest of the nations proposing them. The MIT Emissions Prediction and Policy Assessment (EPPA) model is used to analyze the welfare implications of several prominent proposals, considering both cases where nations must carry out all emissions reductions domestically, and situations where trading in emissions permits is allowed. The consequences of applying two prominent differentiation measures to a global regime using a zero-based allocation of emissions rights is also explored. One conclusion is that a trading regime can yield important benefits in reducing potential conflict within developed nations, and help avoid complicated and divisive negotiations over burden-sharing formulas. / Includes bibliographical references (p. 19-20). / Abstract in HTML and technical report in HTML and PDF available on the Massachusetts Institute of Technology Joint Program on the Science and Policy of Global Change website (http://mit.edu/globalchange/www/)

The Climate Convention calls for stabilization of atmospheric concentrations of greenhouse gases. This paper considers the issues that must be faced in formulating a plan to meet any such target, using a proposed CO2 level of 550 ppmv as an example. We hypothesize a set of "necessary conditions" for such a goal to be achievable, and test set of possible forms of agreement against them using the MIT Emissions Prediction and Policy Assessment (EPPA) model. The results highlight the importance of emissions trading to the feasibility of such a target, and the need for an agreement that can adapt efficiently over time to changing relative economic circumstances in participating nations. / Includes bibliographical references (p. 19). / Abstract in HTML and technical report in HTML and PDF available on the Massachusetts Institute of Technology Joint Program on the Science and Policy of Global Change website (http://mit.edu/globalchange/www/)

Abstract in HTML and technical report in HTML and PDF available on the Massachusetts Institute of Technology Joint Program on the Science and Policy of Global Change website (http://mit.edu/globalchange/www/). / Includes bibliographical references (p. 9-10).

Abstract in HTML and technical report in HTML and PDF available on the Massachusetts Institute of Technology Joint Program on the Science and Policy of Global Change website (http://mit.edu/globalchange/www/). / Includes bibliographical references (p. 12-14).

The impact of uncertainty in the rate of heat and carbon uptake by the deep ocean on climate response to increases in greenhouse gas concentrations is studied by means of numerical simulations with the two-dimensional climate-chemistry model developed in the framework of the MIT Global Change Joint Program. This model incorporates parameterizations of most physical processes, includes fully interactive atmospheric chemistry and calculates carbon uptake by the ocean and, therefore, simulates the main nonlinear interactions taking place in the climate system. At the same time, it is much more computationally efficient than coupled atmosphere-ocean general circulation models. Results of the simulations with calculated CO2 concentrations are compared with those of simulations with a prescribed CO2 increase. This comparison shows that the uncertainty in the increase in global mean surface temperature due to uncertainty in the rate of oceanic heat uptake is enhanced by taking into account the related uncertainty in oceanic carbon uptake, while the uncertainty in sea level rise is decreased. / Includes bibliographical references (p. 5). / Abstract in HTML and technical report in HTML and PDF available on the Massachusetts Institute of Technology Joint Program on the Science and Policy of Global Change website (http://mit.edu/globalchange/www/)

This paper provides a comparative analysis of the economic and political interests influencing the progress of climate negotiation. The primary focus is on the U.S., France, Germany, U.K., Belgium, Netherlands, and the E.U. itself. A discussion of the drivers of policy and differing responses on a national basis is presented to highlight the larger influences at work. The driving factors range across economic and political interests, public concern, bureaucratic goals, scientific evidence, non-governmental organizations, energy industries, and are relevant in each country to varying degrees. Also included is a personal forecast of what can be expected to emerge in the next few months as the current negotiations reach their climax in Kyoto, Japan, in December 1997. / Includes bibliographical references. / Abstract in HTML and technical report in HTML and PDF available on the Massachusetts Institute of Technology Joint Program on the Science and Policy of Global Change website (http://mit.edu/globalchange/www/)

Through a brief look at the science and economics of climate, the authors show that if climate change turns out to be a serious threat, an effective response will require a substantial and very long-term global effort. Today's focus on near-term emissions reductions will be counter-productive if it delays development of the institutions and policy architectures that would be necessary to mount and sustain such an effort over much of the next century. The authors discuss three legacies that our generation could leave that would make this struggle to devise a global response easier: (1) an international climate agreement that could, if necessary, reduce greenhouse gas emissions substantially, at least cost, while being responsive both to changes in our scientific understanding and to evolving political and economic conditions, (2) enhanced technical options that could, if necessary, ease the task of maintaining economic growth while controlling greenhouse gas emissions, and (3) an international system that could, if necessary, transfer substantial sums to developing countries to assist their participation in an emissions control effort. Building these legacies is a huge challenge, but this task merits at least the same sense of urgency that has motivated pre-Kyoto negotiations about short-term CO2 emissions reductions. / Abstract in HTML and technical report in HTML and PDF available on the Massachusetts Institute of Technology Joint Program on the Science and Policy of Global Change website (http://mit.edu/globalchange/www/).

We have derived a parameterization consisting of a set of analytical expressions that approximate the predictions by the CIT Urban Airshed Model for the net export to the environment (i.e., effective emissions) of several chemical species, as functions of fourteen input parameters. For each species, effective emissions are a function of actual urban emissions of this and other species and of other urban domain properties such as meteorology. Effective emissions may be "aged" emissions of primary pollutants or actual production of secondary pollutants. To develop the parameterization we have applied the probabilistic collocation method, which uses the probability density functions of the inputs to generate a set of orthogonal polynomials. These polynomials are then used as the basis for a polynomial chaos expansion that approximates the actual response of the CIT model to its inputs. We assume that seasonal variations can be represented by sinusoidal functions. The parameterization provides a computationally very efficient simulation of the actual model behavior. We have compared the outputs of the parameterization with the outputs of the CIT model, and we conclude that it gives a quite good approximation for effective emissions, at least in the regions of highest probability of the input parameters. This parameterization is applicable to detailed uncertainty and sensitivity analyses and enables computationally efficient inclusion of urban-scale processes as sub-grid scale phenomena in global-scale models. / Includes bibliographical references (p. 29-30). / Abstract in HTML and technical report in HTML and PDF available on the Massachusetts Institute of Technology Joint Program on the Science and Policy of Global Change website (http://mit.edu/globalchange/www/). / Funded by the Comissió Interdepartmental de Recerca i Innovació Tecnològica (CIRIT), Catalunya, Spain and supported by the U.S. National Science Foundation. 95-23616.

This paper is based on a Master of Science thesis submitted to the MIT Technology and Policy Program in May, 1997, and also appeared as Working Paper 97-003 in the MIT Center for Energy and Environmental Policy Research (CEEPR) series. / Includes bibliographical references (p. 29-31). / Abstract in HTML and technical report in HTML and PDF available on the Massachusetts Institute of Technology Joint Program on the Science and Policy of Global Change website (http://mit.edu/globalchange/www/). / Supported in part by a grant from Tokyo Electric Power Company to the Joint Program on the Science and Policy of Global Change, and in part by the U.S. Environmental Protection Agency through Cooperative Agreement. no. CR820662-01-0

A cropland distribution model, which is based on climate, soil and topography, is applied to estimate the area and spatial distribution of global potential croplands under contemporary climate and to assess the effect of transient climate changes projected by the MIT Integrated Global System Model for assessment of climate change. The area of global potential croplands is about 32.91 x 10^6 km^2 under contemporary climate, and increases substantially over the period of 1977-2100 and differs among the three transient climate change predictions, being about +6.7% (2.20 x 10^6 km^2), +11.5% (3.78 x 10^6 km^2), and +12.5% (4.12 x 10^6 km^2) in 2100, respectively. Among twelve economic regions of the world, the Former Soviet Union and the Other OECD Countries regions have the largest increases in potential croplands, while developing countries have little increases in potential croplands. Spatial distribution of potential croplands changes considerably over time, dependent upon the transient climate change predictions. / Includes bibliographical references (p. 9-12). / Abstract in HTML and technical report in HTML and PDF available on the Massachusetts Institute of Technology Joint Program on the Science and Policy of Global Change website (http://mit.edu/globalchange/www/). / Supported by the Joint Program on the Science and Policy of Global Change at the Massachusetts Institute of Technology (CE-S-462041), and the National Institute of Global Environmental Changes of the Department of Energy. No:901214-HAR Supported by the Earth Observing Systems Program of NASA. NAGW-2669