Later this summer, the US Environmental Protection Agency (EPA) will release its final Clean Power Plan, setting carbon emissions limits for existing power plants. Together with a final rule setting standards for new power plants, EPA will create the first nationwide limits on carbon emissions from coal and and natural gas power plants, the largest source of emissions in the US economy.

What does the Republic of Vanuatu, an island nation in the South Pacific, have in common with the state of California? Whether the former’s inundation, brought on by Cyclone Pam in March, was exacerbated by sea-level rise or whether the latter’s prolonged drought might, similarly, be an early harbinger of global warming—each case dashes the illusion that there is time to spare. Even if there were, the long-term benefits of a global greenhouse gas mitigation regime remain an uncertain prospect. In short, a delay in adaptation to unavoidable climatic threats is an unaffordable luxury—action can no longer be averted on account of eventual mitigation measures.

The EU Emissions Trading System (ETS) for carbon dioxide (CO2) is the largest worldwide. Since its inception in 2005, it has experienced allowance price volatility and low overall prices. Generally, the fact that it costs less than anticipated to reduce CO2 emissions would be good news. Instead, these price dynamics are bad news for many because they suggest the program may fail to spark a significant transformation of the economy away from fossil fuel use.

In 1998, the US Environmental Protection Agency implemented the Cluster Rule, its first integrated regulation, to mitigate both air and water pollution from the pulp and paper industry, where emissions and discharges are closely linked. This paper compares the agency’s estimated pollution reductions to an assessment based on the rule’s actual results and draws conclusions for both regulatory impact and retrospective analyses in general.

The US Renewable Fuel Standard was expanded to increase US biofuels consumption to 36 billion gallons per year by 2022, displacing about 25 percent of current fuel demand. This paper examines the US Environmental Protection Agency’s assessment of the benefits and costs of the program and recommends a simplified analytical approach.

Under the US Endangered Species Act, regulators can confer a critical habitat designation on areas considered vital to the recovery of listed species—a move some say results in considerable economic consequences for landowners. However, an expert assessment of the impacts from 1992 to 2011 finds no significant effect on average.