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My recent peer-reviewed publications include:

Probabilistic Assessment of "Dangerous" Climate Change and Emissions Pathways (2005)
S.H. Schneider, M.D. Mastrandrea, PNAS 102, 15728-15735.

Abstract
Climate policy decisions driving future greenhouse gas mitigation efforts will strongly influence the success of compliance with Article 2 of the United Nations Framework Convention on Climate Change, avoiding “dangerous anthropogenic interference with the climate system” (DAI). However, success will be measured in very different ways by different stakeholders, suggesting a spectrum of possible definitions for DAI. The likelihood of avoiding a given threshold for DAI is dependent in part upon uncertainties in the climate system—notably, the range of uncertainty in climate sensitivity. We combine a set of probabilistic global average temperature metrics for DAI with probability distributions of future climate change produced from a combination of several published climate sensitivity distributions and a range of proposed concentration stabilization profiles differing in both stabilization level and approach trajectory—including overshoot profiles. These analyses present a “likelihood framework” to differentiate future emissions pathways with regard to their potential for preventing DAI. Our analysis of overshoot profiles in comparison with non-overshoot profiles demonstrates that overshoot of a given stabilization target can significantly increase the likelihood of exceeding “dangerous” climate impact thresholds, even though equilibrium warming in our model is identical for non-overshoot concentration stabilization profiles having the same target.

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Human-modified temperatures induce species changes: Joint attribution (2005)
T.L. Root, D.P. MacMynowski, M.D. Mastrandrea, S.H. Schneider, PNAS 102, 7465-7469.

Abstract
Average global surface-air temperature is increasing. Contention exists over relative contributions by natural and anthropogenic forcings. Ecological studies attribute plant and animal changes to observed warming. Until now, temperature–species connections have not been statistically attributed directly to anthropogenic climatic change. Using modeled climatic variables and observed species data, which are independent of thermometer records and paleoclimatic proxies, we demonstrate statistically significant "joint attribution," a two-step linkage: human activities contribute significantly to temperature changes and human-changed temperatures are associated with discernible changes in plant and animal traits. Additionally, our analyses provide independent testing of grid-box-scale temperature projections from a general circulation model (HadCM3).

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Probabilistic Integrated: Assessment of "Dangerous" Climate Change (2004)
M.D. Mastrandrea, S.H. Schneider, Science 304, 571-575.

Abstract
Climate policy decisions are being made despite layers of uncertainty. Such decisions directly in.uence the potential for "dangerous anthropogenic interference with the climate system." We mapped a metric for this concept, based on Intergovernmental Panel on Climate Change assessment of climate impacts, onto probability distributions of future climate change produced from uncertainty in key parameters of the coupled social-natural system—climate sensitivity, climate damages, and discount rate. Analyses with a simple integrated assessment model found that, under midrange assumptions, endogenously calculated, optimal climate policy controls can reduce the probability of dangerous anthropogenic interference from ~45% under minimal controls to near zero.

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Dynamics of Climate and Ecosystem Coupling: Abrupt Changes and Multiple Equilibria (2002)
P.A.T. Higgins, M.D. Mastrandrea, S.H. Schneider, Philosophical Transactions of the Royal Society of London Series B-Biological Sciences 357(1421), 647-655.

Abstract
Interactions between subunits of the global climate–biosphere system (e.g. atmosphere, ocean, biosphere and cryosphere) often lead to behaviour that is not evident when each subunit is viewed in isolation. This newly evident behaviour is an emergent property of the coupled subsystems. Interactions between thermohaline circulation and climate illustrate one emergent property of coupling ocean and atmospheric circulation. The multiple thermohaline circulation equilibria that result caused abrupt climate changes in the past and may cause abrupt climate changes in the future. Similarly, coupling between the climate system and ecosystem structure and function produces complex behaviour in certain regions.

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Integrated Assessment of Abrupt Climate Change (2001)
M.D. Mastrandrea, S.H. Schneider, Climate Policy 1, 433-449.

Abstract
One of the most controversial conclusions to emerge from many of the first generation of integrated assessment models (IAMs) of climate policy was the perceived economic optimality of negligible near-term abatement of greenhouse gases. Typically, such studies were conducted using smoothly varying climate change scenarios or impact responses. Abrupt changes observed in the climatic record and documented in current models could substantially alter the stringency of economically optimal IAM policies. Such abrupt climatic changes—or consequent impacts—would be less foreseeable and provide less time to adapt, and thus would have far greater economic or environmental impacts than gradual warming.We extend conventional, smooth IAM analysis by coupling a climate model capable of one type of abrupt change to a well-established energy–economy model (DICE).

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