2023 is on course to be the warmest year on record
Context:

• The year 2023 is on course to possibly become the warmest year in recorded history, with temperatures nearing 1.4°C above the pre-industrial era average.

Globally averaged surface air temperature anomalies

• Chart 1 shows the globally averaged surface air temperature anomalies relative to 1991–2020 for each September from 1940 to 2023. 
• From January to September 2023, the global surface air temperature was 0.52°C above the 1991- ­2020 average and 0.05°C higher than the same period in 2016, the warmest year. 
• During this time frame in 2023, the world’s average temperature was 1.40°C higher than the baseline period of 1850­-1900. 

• Chart 2 shows the average global surface air temperatures for the 30 warmest months between 1940 and 2023, arranged in ascending order.

• Chart 3 shows the global daily surface air temperature (°C) from January 1, 1940 to September 30, 2023, plotted as a time series for each year. 
• The thick black line represents the 1.5°C threshold above pre industrial levels. For more than 80 days in 2023, the global temperature was at least 1.5° higher than pre industrial levels.

• Chart 4 shows the daily Antarctic sea ice extent from 1979 to September 2023. 
• The year 2023 is highlighted; the median for 1991–2020 is shown as a dotted line.  
• Meanwhile, the monthly average Arctic sea ice extent in September 2023 reached its annual minimum of 4.8 million km2 , about 1.1 million km2 (or 18%) below the 1991­-2020 average for September. This value is the fifth lowest in the satellite data record.