The authors draw upon the past decade of experience with carbon markets to test a series of hypotheses about why governments have demonstrated a preference for linking.

The Harvard Project co-sponsored a research workshop in May 2013 examining options for the UNFCCC's Durban-Platform process. This Issue Brief draws from and extends the discussion at the workshop.

The authors analyze global climate policy as the problem of transforming governance of the atmosphere from an open-access to a global-commons regime. They also review several challenges to effecting this transformation.

The author conducts a comparative analysis of fixed and intensity carbon targets, as these might be used in national policy or a multilateral climate agreement. The discussion is relevant to the ongoing UNFCCC negotiations on the 2015 Durban-Platform agreement.

The authors, using data from the recent history of international climate policy to test organizational ecology theory, attempt to explain changes in diversity, growth rates, and composition of organizations dealing with global climate change.

Climate change is a complex long-run phenomenon. The speed and severity with which it is occurring is difficult to observe, complicating the formation of beliefs for individuals. The authors use Google Insights search intensity data as a proxy for the salience of climate change and examine how search patterns vary with unusual local weather. The responsiveness to weather shocks is greater in states that are more reliant on climate-sensitive industries and that elect more environmentally-favorable congressional delegations. Furthermore, they demonstrate that effects of abnormal weather extend beyond search behavior to observable action on environmental issues.

Climate change is a global "free rider" problem because significant abatement of greenhouse gases is an expensive public good requiring international cooperation to apportion compliance among states. But it is also a global "free driver" problem because geoengineering the stratosphere with reflective particles to block incoming solar radiation is so cheap that it could essentially be undertaken unilaterally by one state perceiving itself to be in peril.

Negotiators, business leaders, and others concerned with climate change are attempting to develop market mechanisms that expand and improve upon those provided by the Kyoto Protocol. These "new market mechanisms" might be incorporated into a new international arrangement called for at COP-17 in Durban, South Africa. Dr. Michaelowa explores the paths forward.

A new Harvard-Project Discussion Paper examines the relationships between domestic climate policy and trade. The study compares the output of a range of economic models, using the methodology of the Energy Modeling Forum (EMF).

In a new discussion paper, authors Richard Schmalensee, professor of economics at the Massachusetts Institute of Technology, and Robert N. Stavins, director of the Harvard Project on Climate Agreements, explore four ironic outcomes associated with the otherwise very successful sulfur-dioxide cap-and-trade system created by the Clean Air Act Amendments of 1990.