Production Functions for Climate Policy Modeling: An Empirical Analysis

Quantitative models for climate policy modeling differ in the production structure used and in the sizes of the elasticities of substitution. The empirical foundation for both is generally lacking. This paper estimates the parameters of two-level CES production functions with capital, labour and energy as inputs, and is the first to systematically compare all nesting structures. Using industry-level data from 12 OECD countries, we find that the nesting structure where capital and labour are combined first, fits the data best, but for most countries and industries we cannot reject that all three inputs can be put into one single nest. These two nesting structures are used by most climate models. However, while several climate policy models use a Cobb-Douglas function for (part of the) production function, we reject elasticities equal to one, in favour of considerably smaller values. Finally we find evidence for factor-specific technological change. With lower elasticities and with factor-specific technological change, some climate policy models may find a bigger effect of endogenous technological change on mitigating the costs of climate policy.Climate Policy, Input Substitution, Technological Change

Unilateral Climate Policy, Asymmetric Backstop Adoption, and Carbon Leakage in a Two-Region Hotelling Model

We study backstop adoption and carbon dioxide emission paths in a two-region model with unilateral climate policy and non-renewable resource consumption. The regions have an equal endowment of the internationally tradable resource and a backstop technology. We first study the case of a unilateral stock constraint (e.g. a 450 ppmv carbon dioxide concentration target), and show that the non-abating region makes the final switch to the backstop before the abating region does, though the latter region has two disjoint phases of backstop use if its marginal cost is sufficiently low. Furthermore, we show that the abating region has an inverse N-shaped emission path, with growing emissions in the period for which the ceiling is binding. In addition, there is a phase in which this region has a positive carbon price, but higher emissions than the non-abating region. With a global intertemporal carbon budget instead of a stock constraint, the order of definite backstop adoption is reversed and the abating region’s emissions are always lower. We also show that unilateral climate policy does not lead to international carbon leakage.climate policy, non-renewable resources, backstop technology, carbon leakage, unilateral climate policy

Modeling Linkages Between Climate Policy and Land Use: An Overview

Agriculture and forestry play an important role in emitting and storing greenhouse gases. For an efficient and cost-effective climate policy it is therefore important to explicitly include land use, land use change, and forestry (LULUCF) in economy-climate models. This paper gives an overview and assessment of existing approaches to include land use, land-use change, and forestry into climate-economy models or to link economy-climate models to land-use models.Climate Change, Climate Policy, Modeling, Land Use

Carbon Leakage Revisited: Unilateral Climate Policy with Directed Technical Change

A common critique to the Kyoto Protocol is that the reduction in emissions of CO2 by countries who comply with it will be (partly) offset by the increase in emissions on the part of other countries (carbon leakage). This paper analyzes the effect of technical change on carbon leakage in a two-country model where only one of the countries enforces an exogenous cap on emissions. Climate policy induces changes in relative prices, which cause carbon leakage through a terms-of-trade effect. However, these changes in relative prices in addition affect the incentives to innovate in different sectors. We allow entrepreneurs to choose the sector for which they innovate (directed technical change). This leads to a counterbalancing induced-technology effect, which always reduces carbon leakage. We therefore conclude that the leakage rates reported in the literature so far may be too high, as these estimates neglect the effect of relative price changes on the incentives to innovate.Climate Policy, Carbon Leakage, Directed Technical Change, International Trade

Unintended Detrimental Effects of Environmental Policy: The Green Paradox and Beyond

Well-intended policies aimed at reducing greenhouse gas emissions may have unintended undesirable consequences. Recently, a large literature has emerged showing under what conditions this so-called ‘Green Paradox’ may occur. We review this literature and identify the key mechanisms behind these paradoxical policy outcomes and highlight avenues for future research.climate policy, green paradox, non-renewable resources, scarcity, carbon tax, announcement effects, implementation lag, carbon leakage, backstop technology

Absolute Abundance and Relative Scarcity: Announced Policy, Resource Extraction, and Carbon Emissions

We study the effectiveness of climate change policy in a model with multiple non-renewable resources that differ in their carbon content. We find that, when allowing some time between announcement and implementation of a cap on carbon dioxide emissions, emissions from non-renewable energy sources increase at the time of announcement. There are two channels behind this effect. First, since a binding constraint on emissions restricts energy use during some period of time, more must be extracted during other periods. Second, since low carbon energy sources are relatively more valuable when the policy is implemented, it is optimal to conserve them ahead of enforcement. This might induce a switch to high-carbon resources before the policy is implemented.Climate Policy, Non-renewable Resources, Announcement Effects, Scarcity, Order of Extraction

Climate policy with tied hands: optimal resource taxation under implementation lags

In the presence of implementation lags, announced Pigouvian taxation leads to fossil fuel prices that are too low from society’s perspective. This results in excessive emissions and reduced incentives for green innovation. Such effects are compounded by the presence of pre-existing subsidies to fossil fuel use. We show that the intertemporal resource tax path may need to be modified to optimally take into account the perverse incentives from policy lags and pre-existing policies. We find that it might be optimal to subsidize, rather than tax resource extraction at the instant of implementation

Inflammation Is Associated with Voriconazole Trough Concentrations

Voriconazole concentrations display a large variability, which cannot completely be explained by known factors. Inflammation may be a contributing factor, as inflammatory stimuli can change the activities and expression levels of cytochrome P450 isoenzymes. We explored the correlation between inflammation, reflected by C-reactive protein (CRP) concentrations, and voriconazole trough concentrations. A retrospective chart review of patients with at least one steady-state voriconazole trough concentration and a CRP concentration measured on the same day was performed. A total of 128 patients were included. A significantly (