Sen. John Cornyn (R-Texas) appeared to display a highly questionable understanding of climate change on Twitter, and promptly got dragged over the coals.

The lawmaker on Friday was widely ridiculed for the way he responded to Senate Minority Leader Chuck Schumer’s (D-N.Y.) call for action on the climate crisis. Schumer had tweeted about July 2019 being “the hottest month ever, of any month, on record” and described climate change as “the greatest threat facing our planet.”

Cornyn replied: “It’s summer, Chuck.”