California Gov. Newsom to sign climate bill forcing companies to disclose carbon emissions

California Democratic Gov. Gavin Newsom said he plans to sign a historic but controversial climate bill that would require thousands of major U.S. companies to publicly state their greenhouse gas emissions on their websites.

The bill passed the state legislature last week, and at the time Newsom's office declined to say whether he planned on signing it. During a Climate Week event Sunday in New York, Newsom was asked whether he would sign the legislation, to which he responded, "Would I cede that leadership by having a response that is anything but, 'Of course, I will sign that bill'? No, I will not," "The New York Times" reported.

Newsom also said he wanted "some cleanup on some little language" in the bill, but he did not clarify what changes he intended to make. 

The legislation would require U.S. companies with more than $1 billion in revenue that do business in California to disclose their "emissions of greenhouse gases, criteria pollutants, and toxic air contaminants for each facility," per the bill.

The legislation coincides with a new law that would require companies with more than $500 million in revenue to report their climate-related risks, but they would not need to disclose specific emission amounts. 

The proposal faces strong opposition from conservatives and businesses, many of whom have argued that complying with it would be expensive and difficult.

"The fact that a single state like California would do this is both potentially troubling and potentially promising," Harvard Environmental Economics Director Robert Stavins said. "It could be the case that a company that is valued at $1 billion has $35 of activity in California but is nevertheless affected. But it’s potentially promising because we have such a long history in the U.S. of California being out front on environmental regulation and other states following and the federal government eventually catching up."

The California Chamber of Commerce said last week that the act is "a costly mandate that will negatively impact businesses of all sizes in California and will not directly reduce emissions." 

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