[Correction: Aug. 10, 2026. Due to an editing error, the methane percent increase was originally stated as 166% above pre-industrial. It has been corrected to 164%.] The three dominant greenhouse gases in Earth's atmosphere—carbon dioxide (left), methane (center), and nitrous oxide (right)—all reached new highs in 2023. NOAA Climate.gov image, adapted from Figure 2.59 in State of the Climate in 2023. Background photo from Adobe Stock.