September’s stunning rise of the average global temperature is all but certain to make 2023 the warmest year on record, and 2024 is likely to be even hotter, edging close to the “red line” of 1.5 degrees Celsius of warming above the pre-industrial level that the 2015 Paris climate agreement is striving to avoid.

As of Oct. 10, the daily average Northern Hemisphere temperature had been at a record high for 100 consecutive days.