You can view their disappearance a few ways, experts said — as a flex of executive power, an escalation in the culture war over climate change, or a strategic attempt to erase the scientific foundation for climate policy.

“If you suppress information and data, then you don’t have the evidence you need to be able to create regulations, strengthen regulations and even to combat the repeal of regulations,” Gehrke said.

This isn’t climate denial in the traditional sense. The days of loudly debating the science have mostly given way to a campaign to withhold the raw information itself. “I don’t know if we’re living in climate denial anymore,” said Leah Aronowsky, a science historian at Columbia Climate School. “We have this new front of denial by erasure.”