- 2023 was the warmest year since records began in the 1800s, surpassing the previous record in 2016
- Earth’s greenhouse gas emissions (carbon dioxide, methane, and nitrous oxide) reached record high concentrations
- El Nino conditions contributed to record-high sea surface temperatures, with each month from June to December setting a new record of warming
- Global ocean heat content measured from the surface to a depth of 2000 meters reached new record highs
- Global mean sea level was record high for the 12th-consecutive year, reaching 4 inches above the 1993 average when satellite altimetry measurements began
- Antarctic sea ice set record lows in sea ice extent (coverage) and sea ice area, with 278 days setting new daily record-low sea ice extents
- The Arctic had its fourth-warmest year in the 124-year history of record, with July to September being record warm, and had its fifth-smallest sea-ice extent in 45 the 45-year record
- Heatwaves and droughts contributed to massive wildfires around the world, with 37 million acres burned in Canada alone
