The Climate conference in ParisDecember 2015 is described as “last chance” or “5 to twelve” but in the climate arena there is a risk that we have over-utilized the doomsday vocabulary already in the run-up to Copenhagen, 2009 the better part of a decade ago. For those who have worked on climate issues for several decades it poses a special challenge to calibrate language.Words like “immediate” need careful explanation.

Make wind and solar power even cheaper by opening up access to the electricity gridand ending fossil-fuel subsidies, urge Gernot Wagner and colleagues. Putting a price on carbon dioxide and other greenhouse gases to curb emissions must be the centrepiece of any comprehensive climate-change policy. We know it works: pricing carbon creates broad incentives to cut emissions. Yet the current price of carbon remains much too low relative to the hidden environmental, health and societal costs of burning a tonne of coal or a barrel of oil.

A driving restriction policy, as one of the control-and-command rationing measures, is a politically acceptable policy tool to address traffic congestion and air pollution in some countries and cities in the world. Beijing is the first city in China to implement this policy.

The optimal provision of a state-variable public good, where the global climate is the prime example, is analyzed in a model where people care about their relative consumption.

Climate change is one of the most important challenges facing the world in general and Africa in particular. This article examines economic costs of climate change and climate finance with a focus on Africa.

On 31 March, the Intergovernmental Panel on Climate Change (IPCC) released its latest report on the impacts of climate change on humans and ecosystems (see go.nature.com/ad5v1b). These are real risks that need to be accounted for in planning for adaptation and mitigation. Pricing the risks with integrated models of physics and economics lets their costs be compared to those of limiting climate change or investing in greater resilience.

The introduction of a price on CO2 is expected to be more efficient than prescriptive regulation. It also instantiates substantial economic value. Initially, programs allocated this value to incumbent firms (grandfathering), but the growing movement toward auctioning or emissions fees makes carbon revenues into a payment for environmental services. This paper asks to whom should this payment accrue?

Rigorous, objective evaluation of forest conservation policies in developing countries is needed to ensure that the limited financial, human, and political resources devoted to these policies are put to good use. Yet such evaluations remain uncommon. Recent advances in conservation best practices, the widening availability of high-resolution remotely sensed forest-cover data, and the dissemination of geographic information system capacity have created significant opportunities to reverse this trend.

This article is a good example of EfDs mission: combining policy advice and research. It is based on a consultancy for the US EPA who asked Maureen Cropper to lead a process with a panel of experts to help advise them on what discount rate to use for climate change – and specifically about falling discount rates. This paper (and a longer one in REEP that is forthcoming) is a byproduct of that work.