The GOP megadonor family that gave more than $15 million to President Donald Trumps 2016 campaign maintained its position as a key funder of climate change denial in 2017, dishing out nearly $5 million to nonprofits and think tanks that peddle misinformation about the global crisis, according to their latest tax records.

The continued largesse by the deep-pocketed but secretive Mercer family included a $170,000 donation to the CO2 Coalition , a right-wing think tank that argues Earth benefits from humans pumping carbon dioxide into the atmosphere. William Happer, a retired Princeton physics professor whom Trump recently tapped to lead an ad hoc panel to conduct adversarial scientific peer review of near-universally accepted climate science, co-founded the group in 2015.

Hedge fund tycoon Robert Mercer funds the Mercer Family Foundation, and his daughter, Rebekah Mercer, directs it. The foundations six-figure gift to the CO2 Coalition accounts for a quarter of the $662,203 the coalition raised in 2017. The think tank received its first donation of $150,000 from the Mercers in 2016.

The CO2 Coalition was established out of the defunct George C. Marshall Institute, another conservative think tank that cast doubt on climate science before folding in 2015. Happer, a seasoned climate change denier, left the CO2 Coalition last September to serve as Trumps deputy assistant for emerging technologies on the National Security Council.

Happer has called climate science a cult , claimed Earth is in the midst of a CO2 famine , and said the demonization of carbon dioxide is just like the demonization of the poor Jews under Hitler.