Washington’s push to cut greenhouse gas emissions, expand electric vehicles and grow a clean-energy economy faces new hurdles as the Trump administration rolls back federal climate policies — changes state officials warn could slow progress and jeopardize billions in planned investments.

Department of Ecology Director Casey Sixkiller said the federal government is “attacking the science” that underpins decades of climate action and weakening the state’s ability to meet ambitious targets. Those federal efforts include proposals to overturn the EPA’s 2009 greenhouse gas “endangerment finding,” a legal determination that greenhouse gases threaten public health and cutting off tax credits and infrastructure funds for electric vehicles, solar and wind projects.

“The administration has decided that they’re going to attack the science,” Sixkiller told Austin Jenkins on TVW’s “Inside Olympia.”

“They’re going to undermine decades’ worth of established science and understanding about the way in which fossil fuels are altering our environment,” he said. “And what I continue to remind folks is, you know, you can erase the science, but you can’t erase what people are experiencing.”

Sixkiller said state-level initiatives such as the Climate Commitment Act, the creation of a joint carbon market with California and a plan to phase out sales of new gas-powered cars will continue. “We have no other choice but to continue to move the work forward — to decarbonize our economy and unblock the opportunity that comes with that,” he said.

The state is also responding to the end of federal EV incentives. As $7,500 rebates for electric vehicle purchases expired in September under a Trump-backed budget bill, Gov. Bob Ferguson and Ecology launched “ZEVergreen,” an initiative to explore new tools and policies to keep EV adoption on track. The program will convene utilities, automakers, community groups and industry leaders to design potential state-level incentives, especially for low-income buyers, and to accelerate EV infrastructure investments.

Critics say Washington’s climate policies raise gas prices while delivering too few environmental gains. The Seattle Times editorial board argues less than 14% of carbon auction revenue directly reduces emissions.

The Washington Policy Center, state Sen. Nikki Torres and Rep. Mary Dye sued the departments of Ecology and Commerce this month, alleging they missed a reporting deadline and failed to release 2022 and 2023 emissions data, limiting lawmakers’ and the public’s ability to assess climate progress.

Sixkiller acknowledged that regulatory costs are real but said the alternative — continued reliance on fossil fuels — is worse. “There’s also a cost to the ongoing use of petroleum, and that’s real,” he said. He added that revenue from the Climate Commitment Act is already funding heat pumps, EV access and community resilience projects.

“We can fight climate change, protect natural resources, and restore Puget Sound — and still grow the economy,” Sixkiller said. “Washington has a long history of proving those aren’t competing goals.”