Specification is necessary to rigorous debates and aff and neg innovation

IMPROVING POLICY DESIGN. Political resistance to carbon pricing in many jurisdictions, as well as the emergence of a piecemeal approach to domestic and international climate policy-making, means that it is insufficient to study merely how to price the climate externality in a “first-best” world with no other economic distortions. Although many existing “second-best” policies, such as efficiency standards and support for renewables, are cost-ineffective relative to carbon pricing (14), they continue to be implemented for political, distributional, or other reasons. Research must consider practical dimensions of optimally designing and implementing such policies. First, more rigorous ex post empirical analysis of energy and environmental policies will be critical (15). Policies such as carbon pricing schemes, tradable obligations, fuel taxes, renewable portfolio standards, and energy efficiency standards are already in use in different countries and will become more common as countries try to operationalize their pledges in the United Nations Framework Convention on Climate Change process. But there is often little empirical evidence on individual- or market-level responses to these policies. Existing evidence suggests that behavioral responses to a given policy can drive a wedge between ex ante engineering estimates of program costs and benefits and ex post estimates of true costs and benefits (16). More evidence with rigorous analysis is sorely needed on a range of mitigation and adaptation policies. In the long term, the costs of addressing climate change using current technologies could be very large, which makes technological progress critical. A large body of work on the rate and direction of innovation exists, but research is needed on what combinations of R&D and climate policies shape innovation and difusion of low-carbon technologies (17).