LinkedIn bans Gregory Wrightstone of the CO₂ Coalition after he posted a graphic showing decreasing CO₂ levels: Gregory Wrightstone, a geologist, Executive Director of the CO₂ Coalition and reviewer for the Intergovernmental Panel on Climate Change (IPCC) posted two graphics showing decreasing CO₂ levels. CO₂ Coalition explained the graphics in a statement it published in its newsletter. "The posts were of two charts," the statement said. "One showed that carbon dioxide levels were nearly 6,000 parts per million (ppm) 600 million years ago when many animal life forms first appeared in the Cambrian Era. Another illustrated a 140-million-year decline of CO₂ levels — from 2,500 parts per million (ppm) to the current 420 ppm." According to purported screenshots of an email Wrightstone says he received from LinkedIn, the platform "permanently restricted" his account because he allegedly "violated the LinkedIn User Agreement and Professional Community Policies." LinkedIn did not respond to MRC Free Speech America's request for comment.