Carbon dioxide emissions from the United States rose by 3.4 percent in 2018, reversing a three-year trend of decline, according to a preliminary report released Tuesday by the research firm Rhodium Group.

The spike is the largest annual increase in carbon emissions since 2010, and the second largest since 1996. “The US was already off track in meeting its Paris Agreement targets,” according to the report. “The gap is even wider headed into 2019.”

Given that President Donald Trump campaigned on reviving the coal industry, you might think the spike is related to making good on that promise. But in fact, twice as many coal-fired power plants were closed in 2018 compared to 2017, and coal is not the major culprit in the rise in emissions.

Cold weather, increased natural gas consumption, economic growth, and regulatory rollbacks are the main causes behind the elevated carbon pollution.

For instance, Trump revoked the Obama-era Presidential Climate Action Plan, which proposed strategies for emissions reduction every two years, and pulled the United States out of the Paris Agreement on greenhouse gas mitigation.

The Environmental Protection Agency is in the process of repealing the Clean Power Plan, and is not implementing many of its emissions regulations. In addition to relaxing emission standards for nonrenewable energy sources, Trump also caused setbacks for renewables by imposing a 30 percent tariff on imported solar panels.

Meanwhile, a particularly cold winter from 2017 to 2018 prompted more consumption of oil and gas for heating, according to the report. The growing economy also correlated with increased use of fossil fuels in heavy-polluting sectors such as airplane transportation, trucking, and factories.

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“The tailwinds of Obama administration policy are dissipating,” said Rhodium Group partner Trevor Houser, according to the Guardian. “This year makes it abundantly clear that energy market trends alone—the low cost of natural gas, the increasing competitiveness of renewables—are not enough to deliver sustained declines in US emissions.”