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...

A sufficiently rapidly rising carbon tax may increase near-term emissions compared with the case of no carbon tax. Even so, such a carbon tax path may reduce total costs related to climate change, since the tax may reduce total carbon extraction. A government cannot commit to a specific carbon...

France has a very ambitious environmental-policy agenda, aimed chiefly at cutting greenhouse gas (GHG) emissions but also at dealing with local air and water pollution, waste management and the conservation of biodiversity. The laws that followed the Grenelle de l’environnement encompass...

If governments cannot commit to future carbon tax rates, investments in greenhouse gas mitigation will be based on uncertain and/or wrong predictions about these tax rates. Predictions about future carbon tax rates are also important for decisions made by owners of non-renewable carbon...

Our main message is that it is optimal to use less coal and more oil once one takes account of coal being a backstop which emits much more CO2 than oil. The way of achieving this is to have a steeply rising carbon tax during the initial oil-only phase, a less-steeply rising carbon tax during the...

The increase of fuel extraction costs as well as of temperature will make it likely that in the medium-term future technological or political measures against global warming may be implemented. In assessments of a current climate policy the possibility of medium-term future developments like...

The Green Paradox states that, in the absence of a tax on CO2 emissions, subsidizing a renewable backstop such as solar or wind energy brings forward the date at which fossil fuels become exhausted and consequently global warming is aggravated. We shed light on this issue by solving a model of...

Optimal climate policy is studied. Coal, the abundant resource, contributes more CO2 per unit of energy than the exhaustible resource, oil. We characterize the optimal sequencing oil and coal and departures from the Herfindahl rule. “Preference reversal” can take place. If coal is very dirty...

The Clean Development Mechanism (CDM) is a project-based carbon trade mechanism that subsidizes the users of climate-friendly technologies and encourages technology transfer. The CDM has provided financial support for a large share of Chinese wind projects since 2002. Using pooled...