Changing Planet

California Extends Its Cap-and-Trade Program

In a 28–12 vote on Monday night, California’s Senate approved AB 398 to extend the state’s landmark cap-and-trade program to 2030. Hours later, the bill passed in the state’s Assembly, 55–21. Lawmakers also approved a companion measure, AB 617, aimed at reducing pollution that causes local public health problems. In addition, to win GOP support in the Assembly for the cap-and-trade program, the Legislature passed a constitutional amendment giving Republicans increased input in how the state spends revenues from the sale of emissions allowances—permits to pollute—by requiring, in 2024, a two-thirds vote to approve how they are used.

Gov. Jerry Brown and others have argued that extension of the cap-and-trade program is critical to meet the most aggressive climate goal of any state in the nation—a 40 percent cut in 1990s-level greenhouse gas emissions by 2030—and to send a countering signal to President Donald Trump’s rejection of policies and partnerships aimed at limiting warming (subscription). The program sets a limit on greenhouse gas emissions and allows emitters to buy and sell emissions permits, or allowances. The number of allowances available each year equals the annual limit, and both decrease over time, lowering emissions.

When unveiled for debate last week, the legislation drew the ire of many Republicans and progressive environmentalists, although other influential environmental groups said it represented a reasonable balance and the best chance for advancing the program (subscription). In the end, eight Republicans in the Assembly and one in the Senate voted to extend the program, but some environmental groups remain unhappy, saying the legislation allows polluters too many allowances to emit greenhouse gases and that local air quality is not addressed by the use of offsets, a practice whereby polluters can meet a certain amount of their emissions targets by investing in greenhouse-gas-reducing projects, including those outside California, rather than investing in their own emissions reductions.

The bipartisan, supermajority votes in both the state Assembly and Senate for extension of the program were touted by Senate President pro Tempore Kevin de León as a win for the environment and the economy.

“Californians understand that we can’t truly have a healthy economy that’s built to last without taking meaningful steps to protect public health and preserve a livable environment,” said de León.

 Climate Science: The Debate

Last week U.S. Environmental Protection Agency head Scott Pruitt proposed a televised debate of climate science, whereby a red team would attack mainstream findings and a blue team would play defense. Critics of the idea, which has raised alarm bells among scientists, have argued that it will give viewers the impression that scientists are evenly divided over the fundamentals of climate change, when in fact the vast majority of scientists agree on those fundamentals, and that a debate format would test debating techniques and communication skills, not the evidence.

ClimateWire reported that climate scientists view the debate as a trap because it gives the minority of researchers who question mainstream climate science a stage they’ve not been able to command in peer-reviewed journals (subscription). At the same time, refusal to participate could leave the impression that mainstream climate scientists are hiding something—and would leave skeptics’ assertions unopposed.

Proposal of this debate comes amid news of a U.S. Geological Survey e-mail alert to international scientists warning that the Trump administration’s proposed 2018 budget cuts, if approved, would undermine important data-gathering programs and cooperative studies in a number of areas, including climate change.

NOAA Says 2016 Greenhouse Gas Influence Reached 30-Year High

 According to the National Oceanic and Atmospheric Administration’s (NOAA) Annual Greenhouse Gas Index, the influence of greenhouse gases on atmospheric warming was higher last year than it has been in nearly 30 years (subscription). The greenhouse gas index was intended to provide a straightforward way to report the yearly change in the warming influence of greenhouse gases, reported the New York Times, which noted the steady increase in greenhouse gas emissions since 1990.

“The role of greenhouse gases on influencing global temperatures is well understood by scientists, but it’s a complicated topic that can be difficult to communicate,” the NOAA release states.

As explained by Climate Central, the index takes measurements of 20 key greenhouse gases from some 80 ships and observatories around the world and boils them down into a numerical index that defines the rise from 1700 to 1990 as 100 percent or 1. This year’s number, 1.4, shows that the direct influence of the gases on the climate has risen 140 percent since 1750; 40 percent of that increase has been realized since 1990. The increase is due mostly to human activities and has resulted in warming of 1.8 degrees Fahrenheit above pre-industrial temperatures.

This week NOAA announced that the first half of 2017 was the planet’s second-warmest, behind 2016, since the start of planetary temperature recordkeeping in 1880. A major El Niño, such as that experienced in 2016, tends to increase global temperatures. But as Earth’s temperature has risen because of greenhouse gases, an El Niño isn’t necessary to attain very high temperatures. Years with La Niñas, which tend to cool global temperatures, are today hotter than El Niño years several decades ago.

The Climate Post offers a rundown of the week in climate and energy news. It is produced each Thursday by Duke University’s Nicholas Institute for Environmental Policy Solutions and cross-posted on the Huffington Post and National Geographic NewsWatch. Like us on Facebook, follow us on Twitter, or subscribe to our YouTube channel for more updates.

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Tim Profeta is the founding director of the Nicholas Institute for Environmental Policy Solutions. The Nicholas Institute is part of Duke University and focuses on improving environmental policy making worldwide through objective, fact-based research in the areas of climate change, the economics of limiting carbon pollution, oceans governance and coastal management, emerging environmental markets and freshwater concerns at home and abroad. In his role at the Nicholas Institute, Profeta has continued to use his experience on Capitol Hill to engage in climate change debates. His research has focused, specifically, on market-based approaches to environmental regulations—particularly energy and climate change policy. Other projects engage his expertise in environmental law and air pollution regulation under the Clean Air Act.

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